HomeMy WebLinkAbout07O 2020 East Ravine Alternative Urban Areawide Review (AUAR) and Mitigation Plan Update
Cottage Grove East Ravine AUAR
Update Document November 2020
Page 1
The 2020 Update text and edits are Colored Blue and is bold italicized.
The 2015 Update text is Colored Brown and is bold italicized.
Executive Summary................................................................................................................................. 4
Alternative Urban Areawide Review (AUAR) Worksheet Form ........................................................... 9
1. Title .............................................................................................................................................. 9
2. Proposer ....................................................................................................................................... 9
3. RGU ............................................................................................................................................. 10
4. Reason for EAW preparation ........................................................................................................ 10
5. Location and maps ........................................................................................................................ 10
6. Description ................................................................................................................................... 11
7. Project magnitude data .................................................................................................................. 15
8. Permits and approvals required ..................................................................................................... 17
9. Land use ....................................................................................................................................... 20
10. Cover types ................................................................................................................................... 21
11. Fish, wildlife, and ecologically sensitive resources ........................................................................ 22
12. Physical impacts on water resources .............................................................................................. 31
13. Water Use ..................................................................................................................................... 31
14. Water-related Land Use Management Districts.............................................................................. 31
15. Water surface use .......................................................................................................................... 32
16. Erosion and sedimentation ............................................................................................................ 32
17. Water Quality-stormwater runoff .................................................................................................. 32
18. Water Quality-Wastewater ............................................................................................................ 32
19. Geologic hazards and soil conditions ............................................................................................. 37
20. Solid wastes; hazardous wastes; storage tanks ............................................................................... 38
21. Traffic .......................................................................................................................................... 40
22. Vehicle-related air emissions......................................................................................................... 40
23. Stationary source air emissions ..................................................................................................... 43
24. Dust, odors, noise ......................................................................................................................... 43
25. Sensitive resources ........................................................................................................................ 47
26. Adverse visual impacts ................................................................................................................. 50
27. Compatibility with Plans ............................................................................................................... 50
28. Impact on infrastructure and public services .................................................................................. 51
29. Cumulative impacts ...................................................................................................................... 51
30. Other potential environmental impacts .......................................................................................... 52
31. Summary of Issues ........................................................................................................................ 52
32. Mitigation Initiatives ................................................................................................................... 52
Figure 5.1Project Location 47 54
Figure 5.2AUAR Boundary/USGS Map 48 55
Figure 5.3East Ravine Districts/Aerial Photo 49 56
Figure 5.4Traffic Analysis Zones (TAZ) 50 57
Figure 5.5Existing Municipal Service Area (MUSA) and 2020 MUSA Expansion 51 58
Figure 6.1East Ravine Development Scenario/Master Plan.. .52 59
Figure 6.2Preliminary Phasing Plan 53 60
Figure 9.1Existing Land Use . .54 61
Figure 10.1Land Cover-Natural Resource Inventory 55 62
Figure 10.2Watercourses, Wetlands, Lakes and Streams . 56 63
Figure 10.3Natural Resources Overlay 57 64
Figure 10.3A 57 65
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Update Document November 2020
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Figure 10.3B 57 66
Figure 17.1Existing Storm Water System 58 67
Figure 17.2Proposed Storm Water Syste 59 68
Figure 18.1 Land Use with East Ravine Boundary
Figure 18.2 Sewer Districts with East Ravine Boundary
Figure 19.1Soils Map 60 69
Figure 21.1Existing Roadway System (2003 Functional Class) 62 72
Figure 21.22002 2014 2015 and 2040 ADT (Average Daily Traffic) 63 73
Figure 21.32040 Traffic with Ravine Parkway. 64 74
Figure 25.1Cultural Resources Overlay . 65 75
Figure 27.1City of Cottage Grove 2030 Comprehensive Land Use Plan... 66 76
Figure 27.1ACity of Cottage Grove 2040 Comprehensive 66 77
Figure 27.2Washington County Comprehensive Plan 67 78
Figure 27.3Upper Ravine District Development Update Detail.. ... 68 79
Figure 27.42018 Roadway Functional Classification Map .... .. 69 81
Figure 27.52040 Development staging Map ......................... . 69 82
Table 6.1 - Development Scenario Future Land Use Acreages ............................................................ 14
Table 7.1 - Project Magnitude Data - 20 Year Residential Growth ......................................................... 16
Table 7.2 - Project Magnitude Data - 20 Year Commercial Growth ....................................................... 17
Table 8.1 - Permits and Regulatory Review/Approvals ........................................................................... 18
Table 9.1 - Existing Land Use ................................................................................................................ 20
Table 10.1 - Current 2006 Natural Community Land Cover .................................................................. 21
Table 11.1 - Open Space/Green Land Uses in the Development Scenario ............................................... 28
Table 18.1 - Summary of Current and Future Residential Waste Generation Design Flows (MGD) for 2040 Land Use
.............................................................................................................................................................. 34
Table 18.2 East Ravine Area Future Land Use by District................................................................. 35
Table 18.3 Flow Rates ........................................................................................................................ 36
Table 18.4 East Ravine Area Average Flows ..................................................................................... 36
Table 18.5 East Ravine Area Design Flows ....................................................................................... 36
Table 18.6 Capacity of MCES Connections ....................................................................................... 37
Table 20.1 - Summary of Current and Future Residential Waste Generation ......................................... 39
Table 20.2 - Summary of Current and Future Non-Residential Waste Generation.................................. 39
Table 22.1 - Top Ten Intersections Twin Cities CO Maintenance Area ................................................... 41
Table 23.1 Estimated Greenhouse Gas (GHG) Emissions ................................................................. 43
Table 24.1 - Noise Analysis Instrumentation Summary ........................................................................... 45
Table 24.2 - Nighttime Noise Monitoring Summary................................................................................ 45
Table 24.3 - Peak Hour Traffic Volumes ................................................................................................ 46
Table 24.4 - Distance to Contours ......................................................................................................... 47
Appendix 1 Technical Memorandum. Cottage Grove East Ravine Planning Study: Watermain. Howard R. Green
Company. February 05
Appendix 1A 2006 Water Supply and Distribution Plan
Appendix 2 Technical Memorandum. Cottage Grove East Ravine Planning Study: Sanitary Sewer. Howard R.
Green Company. February 05
Appendix 2A Sanitary Sewer System, Cottage Grove 2040 Comprehensive Plan
Appendix 2B Updated Figure 7-6 from Appendix 2A
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Appendix 3 Technical Memorandum. Secondary Traffic Impacts East Ravine Community. Howard R. Green
Company. February 05
Appendix 4 Technical Memorandum. Traffic Noise and Air Quality Study for the East Ravine Community. Earth
Tech. March 05.
Appendix 5 Stormwater Management Report: Cottage Grove East Ravine. Emmons and Olivier Resources, Inc.
March 05
Appendix 5A 2019 Surface Water Management Plan
Appendix 6 Resolution Ordering AUAR
Appendix 7 Summary of Technical Advisory Committee meetings and Agency Involvement
Appendix 8 Summary of Public Involvement
Appendix 9 Comments Received and Response to Comments
Appendix 10 Adopting Resolution
Appendix 11 East Point Douglas Traffic Study
Appendix 12 Market and Development Context (2040 Comprehensive Plan)
Appendix 13 2020 Natural Hertiage Information System Review
W HAT IS AN AUAR?
An Alternative Urban Areawide Review (AUAR) is authorized under Minnesota Rules Chapter 4410.3610 as an
alternative form of environmental review for development projects. Generally, the AUAR consists of one or more
impacts that the development scenarios may have on these resources as well as public infrastructure services, and a set
of mitigation measures that reduce or eliminate the potential impacts generated by the development. The AUAR is
cts resulting from a sequence of related development projects as opposed to
an Environmental Assessment Worksheet (EAW) or Environmental Impact Statement (EIS) which simply looks at a
iatives.
W HY AN AUAR FOR THIS P ROJECT?
An AUAR was chosen for the Cottage Grove East Ravine project area because it will provide a better framework for
coordinating a number of future development projects that will occur over a long period of time, identifying potential
impacts, and focusing on effective, efficient mitigation strategies.
H OW IS AN AUAR USED?
An AUAR is used as a tool to help parties interested in development within the project area understand the existing
environmental and cultural resources present on a site prior to initiating detailed planning and design. It is also used to
identify key initiatives that must or should be undertaken to minimize negative impacts generated by proposed
development.
Any proposed development in the project area would need to be reviewed for consistency with the AUAR and
Mitigation Plan. If a development plan is not consistent with these documents or other statutory requirements, the
developer may need to conduct additional environmental documentation or review or request an amendment to the
AUAR. Natural and cultural inventory information in the AUAR and the Mitigation Plan will be used to guide
development. Design and construction would proceed only after all approvals and appropriate agreements are complete.
O VERVIEW OF THE AUAR P ROCESS
The City of Cottage Grove last adopted its Comprehensive Plan in October of 2000. This plan identified the eastern
portion of the community as a future phase for development with urban services and generally a low density residential
land use pattern. The Metropolitan Council recently completed a regional sanitary sewer project that makes sanitary
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sewer services available. The City of Cottage Grove began a significant master planning effort in 2002 to help define a
more specific land use and development pattern and to address the implications of future development on a number of
important public infrastructure systems including surface water management, traffic and transportation, sanitary sewer
and public water supply.
The East Ravine Planning District is a roughly 3,800-acre portion of largely undeveloped land stretching along County
establishes a vision of what this area will look like based on how to see the
area developed. The process establishes a framework to ensure that development occurs efficiently and complies with
the vision that Cottage Grove residents and landowners aspire to.
As the availability of developable land in those parts of the city already built up begins to disappear, developers and the
City have turned their sights towards the land in the East Ravine Planning District. The City of Cottage Grove, with a
population of slightly more than 30,000 37,000, wants to avoid the out-of-control growth that other metropolitan
communities have experienced, because such rapid growth can be accompanied by a host of problems such as traffic
congestion and inadequate amenities and infrastructure. Such difficulties could become unmanageable without an
effective planning process because of the unusual size of the area. To date, the growth that has occurred in the East
sires for controlled and manageable growth and has met regional density requirements.
In order to help the City develop a framework that city staff and decision makers will use to evaluate future
development proposals within the area, the City hired a multi-firm consultant team led by the Minneapolis-based
planning firm Hoisington Koegler Group Inc. With the assistance of the consultant team, the City conducted a three year
process that, among other things, helped residents and landowners articulate a vision for the area, as well as establish a
set of goals and objectives for how, where, and what type of development should occur in the East Ravine Planning
District. This AUAR and subsequent required updates is one product of that process.
D ESCRIPTION OF THE D EVELOPMENT S CENARIO
The East Ravine Pre-Design Planning Project consists of roughly 3,800 acre area of largely undeveloped land that
generally lies north of 70th Street, east of County Road 19, and west of Lamar and Kimbro Avenues.
Large areas of predominantly Single Family residential housing are interspersed with a combination of medium and
higher density attached residences to provide a balance of housing opportunities and meet the lifecycle housing needs
and desires of the community. The housing products that have been developed to date have provided a variety of
single and multiple family products and affordability offerings, as well as smaller lot sizes while still meeting the
established densities for the area.
The development scenario identifies two commercial areas or "nodes." One in the Cedarhurst area at 70th Street and
Keats Avenue would have a smaller scale, integrated neighborhood commercial emphasis. This area has not had any
development activity to date. The Cottage View area node in the south near Highway 10/61 is being oriented toward
larger scale community commercial uses. One of the primary goals of the planning process is to design an efficient, safe,
and interconnected system of local and collector streets. This area of the East Ravine saw the 2016 development of a
27-acre commercial site for a Walmart store and included improvements to East Point Douglas Road and the
construction of a roundabout at the Highway 61 interchange. Additional roadway and utility planning are beginning
to occur in this district as the City explores the option of locating and developing a Community Center along Ravine
Parkway in this area.
One of the major features to meet that goal to emerge from the East Ravine planning process is Ravine Parkway. The
parkway will provide both a transportation corridor and a major design feature for the project. As a new collector street,
the parkway will traverse the entire project area beginning in the northwest and meandering east and south towards
Highway 10/61. Portions of the parkway will include natural landscaped areas, trailways, ponds, and wetlands. Other
portions will appear more like Summit Avenue in St. Paul with large green boulevard and median areas. Along the
parkway, local residential street loops will create neighborhood focal points and amenities out of green island areas.
Sidewalks and trails linking area homes to the parkway, will allow safe and convenient movement throughout the
eastern portion of Cottage Grove and connect to the remainder of the community. Two major segments of Ravine
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Parkway were installed in 2018 and 2019 between Keats Avenue and Jamaica Avenue and east of Hinton Avenue.
The missing connection portion that links these two project areas will be completed as development occurs.
Transportation planning also includes the proposal to realign portions of Military Road to correct system design
inefficiencies. The proposal would use a realigned portion of existing Jamaica Avenue to connect southward to 70th
Street. Given the historic role of Military Road, the character and location of the former road alignment will be reflected
in a new system of adjacent local streets and trails.
Major roadways and streets including 70th Street, 80th Street and Keats Avenue (County Road 19) will be established as
green corridors throughout the project area. Expanded right-of-way and easement areas will create larger scale open
ce heritage. These
green corridors will include trails and landscaping treatments that will vary in form and style depending on the specific
location in the project area.
The City is utilizing current management practices and policies to plan for local ponding and surface water management
needs in the planned neighborhoods. The City is also coordinating with the South Washington Watershed District to
address regional storm water drainage needs to minimize redundant expenditures and loss of taxable development area.
I DENTIFICATION OF P OTENTIAL I MPACTS
Natural, Cultural and Physical Resources
Past and current land uses in the project area have primarily been agricultural. Some farmsteads exist which generally
consist of a residential structure and various outbuildings such as barns, sheds or silos. Other uses include large lot
residential development on individual septic systems and private wells, a couple of golf courses, and a campground.
Wetlands are few within the project area. A small complex of wetlands exist west of Jamaica Avenue north of 80th
Street. The primary natural resource feature in the project area is the Central draw or east ravine feature which serves as
a natural drainage way for much of the region. The wetland located west of Jamaica Avenue and north of 70th Street
was officially renamed as Lake Robert in 2018 by the Minnesota DNR and Washington County after receiving a
petition by the required number of signatures.
Natural resources are prominent within the East Ravine Planning District. A large portion of the natural resource base is
contained within the Cottage Grove Ravine Regional Park. Cottage Grove has a commitment to natural resources as
evident by past efforts to identify and protect natural resources. The City of Cottage Grove currently has a Sensitive
Environmental Areas Conservancy Overlay District and a Tree Preservation Ordinance in place providing a foundation
for protection of environmental resources. The impact on these resources from future urban development and
infrastructure systems can be mitigated through the use of these types of existing tools. A significant amount of land in
the East Ravine Pre-design study area falls in the Sensitive Environmental Areas Overlay District.
The Comprehensive Plan contains a significant chapter on Historic Preservation which lays the policy guidance for
decision making relative to preservation of historical and cultural resources. Also serving as a guide for future
community development decision making that acknowledges need for change while providing protection for historically
significant buildings and sites is the Old Cottage Grove Historic District Preservation Planning Report, 2002. The report
contains a comprehensive inventory of all the heritage resources within the district.
Municipal Infrastructure
The City of Cottage Grove presently obtains its raw water supply from deep wells in the Prairie du Chien-Jordan
aquifer. The preliminary plan for the Public Water Supply and Impact improvements in the East Ravine area
consists of approximately 290,000 linear feet (55 miles) of watermain pipe and 3.0 MG of storage to serve an
estimated 5400 units. This system is described in a detailed technical memorandum dated February 7th, 2005 titled
Cottage Grove East Ravine Planning Study Watermain and attached as Appendix 1. Updated water system
information is provided in Appendix 1A 2006 Water Supply and Distribution Plan.
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Sanitary sewer service is provided through the Metropolitan Council Environmental Services regional collection and
treatment systems. The recently completed South Washington County Interceptor project provides services to the East
Ravine Planning District. The preliminary plan for sanitary sewer serving the East Ravine area includes roughly 242,000
feet of sanitary sewer pipe with a total estimated design flow of approximately 12.13 million gallons per day (MGD).
This system is outlined in a technical memorandum dated February 7, 2005 titled Cottage Grove East Ravine Planning
Study Sanitary Sewer and included as Appendix 2. 8.11 million gallons per day (MGD). Updated sanitary sewer
system information and calculations for the East Ravine area are provided in Section 18. Updated City wide sanitary
sewer system information is provided in Appendix 2A, Sanitary Sewer System, Cottage Grove 2040 Comprehensive
Plan.
Storm Water Management
The overall goal of the stormwater practices being proposed for the East Ravine area of Cottage Grove is to minimize
the generation of stormwater runoff created by urbanization and to retain the runoff in a series of natural infiltration
basins rather than concentrate to a single point for collection, treatment and discharge. This approach mimics the current
infiltration patterns that presently exist in the study area of Cottage Grove. The net result will be minimization and, in
some areas, avoidance of discharge of stormwater to surface waters; which in turn will lessen the overall amount of
pollutants associated with the stormwater like the Mississippi River; resulting in less burden on the environment.
The South Washington Watershed District (SWWD) has begun to implement completed a significant percentage of a
regional project which will convey runoff through the East Ravine project area in a system of detention areas and
interconnecting pipes. As of the date of this report, the SWWD has completed land acquisition for an approximately
150-acre area of Neighborhood 1 North. When fully complete, the SWWD system will create a stormwater link to the
Mississippi River. The SWWD has expressed a willingness to work with the City of Cottage Grove towards a combined
City/Watershed District stormwater management system. The proposed Cottage Grove stormwater plan utilizes the
natural detention areas acquired by the SWWD, but does not anticipate the need to rely on the proposed connecting
storm drains, thereby protecting the Mississippi River and minimizing inputs to Cottage Grove Ravine Regional Park
from the effects of local urbanization.
The detailed storm water management report documenting the approach to the East Ravine area is included as Appendix
5. Updated storm water system information is provided in Appendix 5A, 2019 Surface Water Management Plan.
and watershed improvements have been coordinated.
Traffic Related Impacts
The East Ravine planning project evaluated the traffic impacts of the development scenario. The East Ravine area is
expected to reach full build-out in 20 years. However, the travel demand model used for the traffic analysis used Year
2020 conditions in Washington County with full build-out of the East Ravine. The detailed methodology and analysis of
traffic impacts is contained in a technical memorandum included as Appendix 3 of the AUAR. Seven key roadways
(broken into twenty-four segments for analysis) and eighteen key intersection listed below were selected for this study
because they will provide primary access to the regional road system and will likely be the primary roadways when the
area develops.
Key Roadways
US 61 between Glen Road and Kimbro Avenue
CSAH 20 (Military Road) between Ideal Avenue and Lamar Avenue
Ravine Parkway
CSAH 22 (70th Street) between US 61 and CSAH 19 (Keats Avenue)
80th Street between US 61 and Kimbro Avenue
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Jamaica Avenue between CSAH 20 (Military Road) and US 61
CSAH 19 (Keats Avenue) between Dale Road and US 61
Lamar Avenue/Kimbro Avenue between 70th Street to US 61
Key Intersections
US 61/70th Street Ramps (3 intersections)
US 61/80th Street Ramps (2 intersections)
US 61/Jamaica Ave Ramps (2 intersections)
US 61/CSAH 19 (Keats Avenue) Ramps (2 intersections)
US 61/Kimbro Avenue
80th Street/Jamaica Avenue
80th Street/CSAH 19 (Keats Avenue)
80th Street/Kimbro Avenue
CSAH 20 (Military Road)/Lamar Avenue
CSAH 22 (70th Street)/CSAH 19 (Keats Avenue)
CSAH 22 (70th Street)/Jamaica Avenue
CSAH 20 (Military Road)/Jamaica Avenue
CSAH 20 (Military Road)/CSAH 19 (Keats Avenue)
An operation analysis was completed for roadway segments and intersections. Roadway operations were evaluated by
comparing average daily traffic counts with level of service bar charts developed using methodologies from the
Highway Capacity Manual. Intersections were evaluated using the expected intersection delay. In the existing year, the
intersection of CSAH 22 (70th Street)/Jamaica Avenue is the only intersection operating below the desired level of
service. Forecasted average daily traffic volumes were used to estimate future roadway operations. These forecasted
were developed using the Washington County 2020 Travel Demand Model. Assuming the existing geometry, two of the
seven roadways operated under congested conditions. Eleven of the eighteen intersections operated below the desired
level of service. The following projects are recommended to mitigate the impacts:
Roadway Improvements
Reconstruct CSAH 20 (Military Road) as a four-lane facility with turn lanes.
Reconstruct CSAH 19 (Keats Avenue) as a four-lane facility with turn lanes.
Realign the intersection of CSAH 20 (70th Street) and CSAH 19 (Keats Avenue) to be the major connection to US 61
and close the intersection of CSAH 20 (Military Road) and CSAH 19 (Keats Avenue) (Roundabout installed and
Realignment Complete 2015)
Discuss the possible closure of US 61 and Kimbro Avenue and a possible future interchange at US 61 and TH 95
(Manning Avenue) with Mn/DOT and other authoritative jurisdictions.
Intersection Improvements (Installation of Traffic Signals at the Following Locations)
US 61 SB Ramp/CSAH 22 (70th Street)
US 61 SB Ramp/Jamaica Ave
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US 61 NB Ramp/Jamaica Avenue
US 61 SB Ramp/CSAH 19 (Keats Avenue)
US 61/Kimbro Avenue, 80th Street/Jamaica Avenue
80th Street/CSAH 19 (Keats Avenue)
CSAH 22 (70th Street)/CSAH 19 (Keats Avenue)
CSAH 22 (70th Street)/Jamaica Avenue
Jamaica Avenue/Ravine Parkway
CSAH 19 (Keats Avenue) /Ravine Parkway
M ITIGATION I NITIATIVES
The Mitigation Plan identifies key steps that the City will take to mitigate potential impacts identified in the AUAR. In
addition to general mitigation initiatives, the mitigation plan includes strategies in the following areas:
Natural and Physical Resources
Cultural Resources
Land Use Management
Erosion Control and Sedimentation
Water Supply and Appropriation
Wastewater System
Storm Water Management
Traffic Management
This section consists of the Environmental Assessment Worksheet (EAW) form and response to questions as modified
by Environmental Quality Board (EQB) AUAR Guidance as of July 2004 September 2008 December 2015 The EAW
question is shown in bold uppercase text, AUAR guidance is shown in faded italicized text, and the response to the
question is shown in regular text.
The 2015 Update text is Colored Brown and is bold italicized.
The 2020 Update text and edits are Colored Blue and bold italicized.
1. T ITLE
Cottage Grove 2015 East Ravine AUAR Update.
Cottage Grove 2020 East Ravine AUAR Update.
2. Proposer
John M. Burbank
City of Cottage Grove
12800 Ravine Parkway South
Cottage Grove, MN 55016
jburbank@cottage-grove.org
jburbank@cottagegrovemn.gov
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3. RGU
City of Cottage Grove
12800 Ravine Parkway South
Cottage Grove, MN 55016
www.cottage-grove.org
www.cottagegrovemn.gov
4. R EASON FOR AUAR AND UPDATE PREPARATION
In conjunction with the East Ravine Master Planning process, the City of Cottage Grove prepared the environmental
assessment document in the form of an AUAR to understand the cumulative impacts of future development and to
develop mitigation strategies to minimize potential environmental impacts. The East Ravine AUAR and Mitigation
Plan received final approval in March of 2006 and
Plan amendment.
The Cottage Grove 2015 East Ravine AUAR Update Report is being completed in conformance with MN Rules
4410.3610, Subpart 7(A).
The Cottage Grove 2020 East Ravine AUAR Update Report is being completed in conformance with MN Rules
4410.3610, Subpart 7(A). In addition, the adoption of the 2040 Comprehensive Plan modified the land use on several
properties from Commercial to Mixed use.
5. L OCATION AND MAPS
The AUAR Project Area is located on the east side of the City Cottage Grove. Figure 5.1 shows the project location.
No changes have been made in relation to the scope, size or location of the AUAR project area since the
original AUAR was approved.
County: Washington
City: Cottage Grove
Locations: The Cottage Grove East Ravine Planning District, is an approximately 4,000 acre portion of largely
undeveloped land stretching along the east side of County Road 19 from Highway 61 north to the City of Cottage
Ideal Avenue.
The following figures are included within the AUAR:
Figure 5.1Project Location
Figure 5.2AUAR Boundary/USGS Map
Figure 5.3East Ravine Districts/Aerial Photo
Figure 5.4Traffic Analysis Zones (TAZ)
Figure 5.5Existing Municipal Service Area (MUSA) and 2020 MUSA Expansion
Figure 6.1East Ravine Development Scenario/Master Plan
Figure 6.2Preliminary Phasing Plan
Figure 9.1Existing Land Use
Figure 10.1Land Cover
Figure 10.2Watercourses, Wetlands, Lakes and Streams
Figure 10.3Natural Resources Overlay
Figure 17.1Existing Storm Water System
Figure 17.2Proposed Storm Water System
Figure 19.1Soils Map
Figure 21.1Roadway System
Figure 21.22000 2014 2015 Average Daily Traffic
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Figure 21.3Build Out Average Daily Traffic
Figure 25.1Cultural Resources Overlay
Figure 27.1City of Cottage Grove 2030 Comprehensive Land Use Plan
Figure 27.1ACity of Cottage Grove 2040 Comprehensive Land Use Plan
Figure 27.2Washington County Comprehensive Plan
Figure 27.3Upper Ravine District Development Update Detail
Figure 27.42014 2018 Roadway Functional Classification Map
The following figures have been added to the AUAR.
Figure 10.3AGrassland/Shrubland Map
Figure 10.3BLawn/Landscaping Map
Figure 18.1 Land Use with East Ravine Boundary
Figure 18.2 Sewer Districts with East Ravine Boundary
Figure 27.1ACity of Cottage Grove 2040 Comprehensive Land Use Plan
Figure 27.3-- Development Update Exhibit 2020 Update
Figure 27.42014 2018 Roadway Functional Classification Map
Figure 27.52040 Development Staging Map
The planned development scenario for the East Ravine has not been modified since the adoption of the
AUAR, but certain components of the plan need to be modified to address current market conditions and
development practices. Smaller lot sizes appear to be the biggest change from the original development
scenario in the residential subdivisions that have been approved. In exchange for the relaxation of the
standards, the City has been exacting extensive park, open space and trailway improvements. The higher
density resulting from the decreased lot sizes are consistent with regional growth policies.
The residential development that occurred since 2015 was significantly in conformance with the planned
neighborhood layouts and internal local road networks. The trend for smaller lot sizes and housing product
size continued since 2015 and reflects the current market demand for different housing opportunities and
price points. Regional density goals have been maintained on average in the planning area.
6. D ESCRIPTION
The original development scenario was derived with input from a group of area residents on a Community Advisory
Team, City Advisory Commissions, and from two workshop meetings of the City Council and Planning Commission
held in the spring and summer
features, transportation corridors, greenways, and development patterns to establish a plan for new neighborhood areas,
distinct to Cottage Grove, interconnected by a network of parks, trails, and storm water drainage features.
The development scenario is illustrated in Figure 6.1 and consists of the following components:
Housing - Large areas of predominantly Single Family residential housing are interspersed with a combination of
medium and higher density attached residences to provide a balance of housing opportunities and meet the lifecycle
housing needs and desires of the community. Housing types include single family detached, villas, multi-family attached
(townhomes, rowhouses, twin homes) and multi-family stacked (condominiums and apartments). Housing densities
type neighborhoods such as Cedarhurst ranging from 6 to 12 units per acre. The most intense residential uses would be
located in the Cottage View and Cedarhurst areas with densities in the 6 to 12 unit per acre range, and in the new mixed
use land use districts, which would allow for a density of up to 40 units per acre for select projects.
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Since adoption of the AUAR, only four single family residential developments have been approved by the City and
constructed. The projects were located in Upper Ravine Neighborhood One North and consisted of 278 total
single family lots. The acreage for these subdivisions totaled 149 gross buildable acres and was within the scope
of the original development scenario.
Since adoption of the AUAR through 2019, there were, only four nineteen single family residential developments
have been approved by the City. The projects were located in Upper Ravine Neighborhood One North and
consisted of 278 747 total single family lots. The acreage for these subdivisions totaled 149 310 gross buildable
acres and was within the scope of the original development scenario with an average density of 2.40 units per
gross acre.
Commercial The development scenario identifies two commercial areas or "nodes." One in the Cedarhurst area at
70th Street and Keats Avenue would have a smaller scale, integrated neighborhood commercial emphasis. This pattern
of commercial use would typically include smaller building footprints on smaller parcels. The Cottage View area node
in the south near Highway 10/61 is more oriented toward larger scale community commercial uses
. Larger parcels are required for this type of use. Floor area
ratios (square feet of gross leasable area to gross site acreage) for commercial uses would range from 0.2 for the larger
scale community commercial to .5 for the more village oriented commercial uses.
Since adoption of the AUAR, the only commercial development activity that was approved was an 180,000
square foot Walmart store located on 23.5 acres of commercially guided land located in the Cottage View area of
Neighborhood One South. Additional traffic studies were completed in conjunction with the development review
process for this project. The recommendations found in the traffic studies were incorporated into the approval of
the Walmart project. Construction for this project was completed in the first quarter of 2014. This project is
within the scope of the original development scenario. The Traffic Study is included as Appendix 11. No
additional commercial activity has occurred in the East Ravine planning area.
Transportation - One of the primary goals of the planning process is to design an efficient, safe, and interconnected
system of local and collector streets. One of the major features to meet that goal that emerged from the process is the
East Ravine Parkway which essentially runs through both neighborhoods and provides a connecting link for the entire
East Ravine community. The parkway will provide both a transportation corridor and a major design feature for the
project. As a new collector street, the parkway will traverse the entire project area beginning in the northwest and
meandering east and south towards Highway 10/61. Portions of the parkway will include natural landscaped areas,
trailways, ponds, and wetlands. Other portions will appear more like Summit Avenue in St. Paul with large green
boulevard and median areas. Along the parkway, local residential street loops subdivision entrance outlots and buffers
will create neighborhood focal points and amenities out of green island areas. Sidewalks and trails linking area homes to
the parkway, will allow safe and convenient movement throughout the eastern portion of Cottage Grove and connect to
the remainder of the community.
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Since the adoption of this AUAR, the East Ravine Parkway was formally named as Ravine Parkway South by the
Cottage Grove City Council. Two segments of this roadway have been completed to date in conjunction with the
construction of the Washington County South Service Center and the new Cottage Grove City Hall and Public
Safety facility. The City is currently working with Washington County on identifying controlled access points
within Upper Ravine Neighborhood One North, which includes segments of the Ravine Parkway. The City has
also coordinated with Washington County on the realignment of the intersection of 70th Street and Keats Avenue
Plan. This realignment project is currently under construction
and is anticipated for completion in the spring of 2015. These roadway projects were analyzed in the original
AUAR and adopted Comprehensive Plan. Portions of the 70th Street realignment were incorporated into the
South Washingtegional storm sewer extension project. This portion of the
project was included in a separate AUAR that was prepared by the SWWD. Access to a copy of this document can
be found at http://www.swwdmn.org/. In 2018 and 2019, three additional segments of the parkway were
constructed between Keats Avenue and Hinton Avenue. Since the last update to the AUAR, Washington County
has adopted a county access management plan that was supported by Cottage Grove.
Transportation planning also includes the proposal to realign portions of Military Road to correct system design
inefficiencies. The proposal would use a realigned portion of existing Jamaica Avenue to connect southward to 70th
Street. Given the historic role of Military Road, the character and location of the former road alignment will be reflected
in a new system of local streets and trails.
Green Corridors - Major roadways and streets including 70th Street, 80th Street and Keats Avenue (County Road 19)
will be established as green corridors throughout the project area. Expanded right-of-way and easement areas will create
space heritage. These green corridors will include trails and landscaping treatments that will vary in form and style
depending on the specific location in the project area. Park and recreation features will also be included in these green
corridors or will be connected to them via trails and sidewalks.
All new developments along the major roadways within the district are required to have a landscape buffer
component that averages 75 feet and is protected by easements and covenants. The design criteria within this
dedicated buffer area are expected to be consistent from subdivision to subdivision along the major roadways.
The required buffer area was successfully implemented in the design approval for the four single family
residential subdivisions recently approved along Ravine Parkway, 70th Street, and Jamaica Avenue. This
action has been implemented as development occurs adjacent to the major roads in the planning area.
As a component of the 70th Street realignment project and in conjunction with the concept review of several
new residential developments for the Upper Ravine Neighborhood One North that have occurred recently, the
City has begun to refine the design concepts for the new Historic Military Road Trail Corridor and new
intersection geometrics for Military Road and Jamaica Avenue in Woodbury. Completion of this realignment
project is expected in 2015 or 2016 depending on development activity. Portions of Military Road have been
permanently closed as a result of adjacent residential development. The new historic trail segments include
landscaping, architectural benches, interpretive signage, and prairie restorations. The Jamaica Avenue
upgrade and realignment have yet to occur.
Surface Water Management - The City is utilizing current management practices and policies to plan for local
ponding and surface water management needs in the planned neighborhoods. The City is also coordinating with the
South Washington Watershed District (SWWD) to address regional storm water drainage needs to minimize redundant
expenditures and loss of taxable development area. The overall goal of the stormwater practices being proposed for the
East Ravine area of Cottage Grove is to take advantage of the suitable soils in this area to infiltrate urban runoff in
both City and SWWD facilities. minimize the generation of stormwater runoff created by urbanization and to retain the
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runoff in a series of natural infiltration basins rather than concentrate to a single point for collection, treatment and
discharge. This approach mimics the current infiltration patterns that presently exist in the study area of Cottage Grove.
The net result will be to use infiltration in a strategic way to manage urban runoff volumes and pollutant loads within
the East Ravine area. minimization and, in some areas, avoidance of discharge of stormwater to surface waters;
which in turn will lessen the overall amount of pollutants associated with the stormwater like the Mississippi River;
resulting in less burden on the environment.
Development Staging/Phasing Development staging for the project is for Upper Ravine Neighborhood 1 to be served
first followed by Neighborhood 2. Services to Neighborhood 1 could begin as soon as all approvals and permits are in
place. Neighborhood 2 is anticipated to be provided infrastructure facilities by roughly 2015 or when Neighborhood 1
has become substantially developed. A phasing plan is included as Figure 6.2.
The following table provides a breakdown of 2040 Future Land Use by acreage according to Neighborhood 1 and
Neighborhood 2 and the total project area. Road right-of-way is not included in these land use acreages.
A major portion of the planned trunk sanitary sewer for the Upper Ravine District was installed by the City in
2007 in order to serve the first two residential subdivisions located west of Jamaica Avenue. The additional two
residential developments approved in this district are benefiting from the use of this infrastructure. Infiltration
has continued to be utilized in development areas where allowed
Since the adoption of the AUAR, the SWWD has completed four of the five phases of the Central Draw Overflow
and Storage Project.
When fully developed, the East Ravine will contain the following mix of land uses:
Table 6.1 - Development Scenario Future Land Use Acreages
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The residential and commercial development that occurred within the East Ravine did not modify the described
land use categories identified in the table 6.1. Within the civic campus land use area, the City and Washington
acres of land. . The
remaining 24.28 acres remain vacant and may be developed further in the future with a regional joint effort
public safety training facility. The 45,508 square foot HERO Center training facility was constructed on the 9.02-
acre balance of the civic campus in 2019. The 2040 ComprehensivePlan converted the 129 acres of Commercial
land use to Mixed Use. The City is currently updating the zoning ordinance to reflect the new Mixed Use
classification.
7. P ROJECT MAGNITUDE DATA
The following tables represent project magnitude data for the Cottage Grove East Ravine project. This data was
generated with an understanding of the market forces and land development interests in the project areas trade market.
Residential and commercial development trends were reviewed in conjunction with building permit data to support
market research conducted by McComb Group, Ltd. in Fall of 2003. A report titled East Ravine Development Potential:
Retail and Residential completed by the McComb Group was published in December of 2003 and is available from the
City.
The Cottage Grove Demographic Characteristics and Retail Sales Potential Study was updated in September
2009.This Study is included in the Appendix of this report.
As a part of the 2040 Cottage Grove Comprehensive Plan, a Market and Development Context Report was
prepared in 2016. This report is included in the Appendix 12 for reference.
Residential Demand: Residential demand was estimated at over 10,000 new homes by 2025. The East Ravine planning
process was conducted to test the land capacity for new housing consistent with City policies and directions provided
through the planning process. More detailed site design testing and planning resulted in approximately 6,500 housing
units over the next 20 year period as depicted in Table 7.1 below. Housing unit types would be mixed between single
family detached at 46%, single family attached (twinhomes, townhomes) at 24% and multi-family stacked
(condominiums, apartments) at 30%. Neighborhood 1 and Neighborhood 2 are made up of a variety of land uses,
as presented in Table 7.1. Housing unit types would be mixed between single family detached at 80%, single
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family attached (twin homes, townhomes) at 12%, and multi-family stacked (condominium, apartments) at 8%.
Average densities across all residentially guided land areas would be slightly over 4 units per net acre. Density is based
on developable land area less major road right-of-way, protected water bodies, NWI wetlands, lands owned by the South
Washington County Watershed District for stormwater management, and park/open space areas not intended for
development. Residential densities in Neighborhood 2 also do not include the land use category of 2 acre lots un-
sewered. If this land area were to be included in the calculation for density, Neighborhood 2 would have a net
density of 2.8 units per acre as opposed to 4.4. Residential densities do not include Rural Residential land uses.
Densities are presented in Table 7.1.
Table 7.1 - Project Magnitude Data - 20 Year Residential Growth
The timing of the residential growth in Cottage Grove was delayed by the downturn in the economy and housing
market which impacted the development staging of the growth and is covered elsewhere in this document.
Unless subjected to a major change in regional forecasting methodologies, the projected growth figures
included below are still considered accurate minus the 120 single family units platted to date.
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Note: ional parks
and greenways and major road right-of-way.
There are two primary Commercial land use nodes in the project area. Neighborhood 1 includes the bulk of the
commercial area at the Cottage View area at CR 19 and Highway 61. The other area is the Cedarhurst area at 70th
Street east of CR 19 in Neighborhood 2. Collectively, these two areas could accommodate approximately 850,000
square feet of new commercial retail development. The East Ravine Development Potential: Retail and Residential
market study provided the research to support this level of retail growth over the next 20 year period.
In 2012, the City Council approved a 23.5-acre commercial development that is located in the Cottage View
Area of Neighborhood 1 South. The project completed construction in March of 2014. The new Mixed Use
zoning ordinance that is being drafted by the City to coincide with the 2040 land use modification from
Commercial to Mixed Use would include vertical mixed use residential in addition to traditional retail based
commercial and office uses within the East Ravine. At this time, it is premature to estimate what the ratio of
units and density that the market would bear. Infrastructure and roadway improvements will be analyzed and
required as development occurs.
Table 7.2 - Project Magnitude Data - 20 Year Commercial Growth
Commercial Total Units
Acres Sq. ft.
Neighborhood 1 - Undeveloped 64 200,000
Neighborhood 1 - Developed 0
Neighborhood 2 - Undeveloped 62.5 470,000
Neighborhood 2 - Developed 23.5 180,000
Total Project Area 150 850,000
There have been no modifications to the information reported in Table 7.2.
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8. P ERMITS AND APPROVALS REQUIRED
Table 8.1 presents a list of known local, state, and federal permits and approvals. The specific permits and approvals
will depend on the type and magnitude of a particular development project. Additional consultation with city and agency
staff will be needed to clarify whether a permit or approval is necessary.
Table 8.1 - Permits and Regulatory Review/Approvals
There have been no modifications to the information reported in Table 8.1.
There have been no modifications to the information reported in Table 8.1.
Type of Permit/review or Regulatory Citation
Unit of Government approval (as may be noted)
City of Cottage Grove Subdivision Approval
Planned Unit Development
Approval
Rezoning
Flood Fringe and Floodway Overlay
Conditional Use Permit Approval
Grading Permit/Drainage and
Stormwater
Site Plan Review Approval
Comprehensive Plan Amendments
Zoning Ordinance Amendments
Variance
Washington County Roadway Access Permit
Utilities in Right-of-Way Permit
Minnesota Department of Utility Crossings Permit MN Statute 103G, MN Rules
Natural Resources 6115.0810
Federal Endangered Species
Preservation Act of 1973, as
Natural Heritage Program amended in 1978, 1982, and
Coordination 1988; MN Statutes Chapter
84.0895; MN Rules Chapter
6134
Wetland Permit
U.S. Army Corps of Engineers Clean Water Act Section 404/10 Section 404 Of The Clean
Wetland Permits Water Act Title 33CFR26 -
Water Pollution Prevention and
Control Subchapter IV - Permits
and Licenses
Minnesota Department of Health Water Main Plan Review MN Rules 4720
Minnesota Pollution Control NPDES Permit MN Statute 115, MN Rules
Agency 7002
Sanitary Sewer Extension Permit
401 Water Quality Certificate
Surface Water Discharge Permit
Wastewater Permit
Indirect Source Permit (ISP)
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Type of Permit/review or Regulatory Citation
approval (as may be noted)
Unit of Government
South Washington County Grading/Drainage/Storm sewer
Watershed District Permit
Metropolitan Council
Environmental Services
Section 106 of the Historic
Preservation Act, Protection of
Minnesota State Historic Historic Properties" (36 CFR
Cultural Resource Coordination
Preservation Office Part 800), MN Statutes 138.31-
.42, MN Private Cemeteries
Act- MN Statute 307.08
Utilities in Right-of-Way Permit
Minnesota Department of
Transportation
Access Permit
Minnesota Environmental Minnesota Rules 4410
Environmental Assessments (AUAR)
Quality Board (EQB)
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9. L AND USE
Past and current land uses in the project area have primarily been agricultural. Some farmsteads exist which generally
consist of residential structures and outbuildings such as barns, sheds or silos. Other uses include large lot residential
development on individual septic systems and private wells. This type of use is primarily focused on the eastern edge of
the project area in what is commonly known as Old Cottage Grove, along Military Road or along Keats Avenue. Figure
9.1 illustrates existing land use in the project area.
Table 9.1 - Existing Land Use
There have been no changes in the information reported in Table 9.1.
The steady development in the East Ravine is constantly shifting the existing land use acreage as properties
develop in accordance with the East Ravine Master Plan and adopted comprehensive plans. No ongoing or
aggregate study has been completed to date to track these inevitable conversions as areas in the East Ravine are
developed.
Adjacent land uses consist of a combination of urban land uses to the west of the project area (predominantly a single
family, low density residential use) and rural land uses to the east of the project area (farm fields). Highway 61 is
located to the south of the project area and The City of Woodbury is located to the north. In Woodbury, land uses are
currently agriculture oriented with longer term plans for residential growth.
A site owned by 3M Corporation is located at the northern boundary of Cottage Grove, east of CR 19. The site has
extensively been monitored by both 3M Corporation and the Minnesota Pollution Control Agency. Additional
documentation as to the status of this site is available through the City of Cottage Grove or through the MPCA.
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10. C OVER TYPES
Cover Type Map
Figure 10.1 shows natural resources such as threatened and endangered species and cover types such as cropland,
basswood forest, brushland, coniferous plantation, dry oak forest, dry oak savanna, dry prairie, lowland hardwood
forest/wet meadow, lowland hardwood forest, maple-basswood forest, mesic oak forest, mixed hardwood forest, oak
woodland-brushland, old field, and wetland/open water marshes. Figure 10.2 presents mapping of watercourses,
wetlands, lakes, and floodplains. Figure 9.1 shows existing development patterns.
Current natural community land cover is presented in Table 10.1. The future level of impact cannot be predicted at this
time since specific development plans are not in place.
Table 10.1 - Current 2006 Natural Community Land Cover
Land Classification Existing Acres Land Classification Existing Acres
Coniferous Forest 5.14 Maple-Basswood 63.13
Forest
Agricultural Land 2050.15 Mesic Prairie 2.38
Deciduous Forest 8.35 Mixed 36.03
Coniferous/Deciduous
Forest
Dry Prairie 17.73 Oak Forest 682.28
Floodplain Forest 1.60 Oak Savanna 57.49
Grassland/Brushland 240.70 Oak 149.46
Woodland/Brushland
Other/Transitional 25.65
Impervious Surfaces 220.11
Land
Lawn/Landscaping 252.02 Planted Coniferous 62.02
Forest
Lowland-Hardwood 28.13 Wetland 104.92
Forest
Total Acres 4007.29
Consistent with the modifications in land use through development, modifications to land cover within the East
Ravine are not actively quantified due to a lack of purpose as development occurs within the scope of approved
land use plans within the planning district.
Overlay
Figure 9.1 presents existing land use and Figure 6.1 presents the development scenario representing future land use that
can be viewed in conjunction with Figures 10.1 Natural Resources and 10.2 Water Features. Cottage Grove has a
commitment to natural resources and has prepared a Natural Resource Inventory completed by BRAA in 1998.
Community woodlands and wetlands are also
Conservation Act. Figure 10.3 presents a Natural Resources Overlay identifying Environmentally Sensitive Features as
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With urban development, the face of the existing landscape is inevitably and irreparably modified. The City
recognizes that the areas identified for growth on the approved 2030 and 2040 land use plans will shift the ratios
the Tree Preservation Ordinance, the natural communities that have a significant local value have and will be
preserved. The current development review process does not break out the land use classification changes to the
level of detail identified initially in Table 10.1 and is not a component of review for development of the East
Ravine Planning Area.
11. F ISH, WILDLIFE, AND ECOLOGICALLY SENSITIVE RESOURCES
Wildlife and Fish Resources
There is a variety of wildlife in the AUAR study area due to the diverse types of habitat available. Wetlands, woodlands,
grasslands, and croplands found in the area provide good cover and habitat for many common species found in the upper
Midwest. Development will result in an overall loss of habitat quantity and quality in the area. In the short term, animals
will be displaced by construction activities, moving into other areas where they will be forced to compete for resources
and typically experience higher rates of mortality than resident wildlife. In the long term, the ability of the area to
support wildlife will be diminished. The frequency of conflicts between humans and wildlife will increase in the form of
nuisance wildlife complaints.
The statements in this section remain unchanged.
The statements in this section remain unchanged.
Wetlands
There are approximately 105 acres of wetlands within the project area. Wetlands were identified using National Wetland
Inventory (NWI) Maps, the Cottage Grove Natural Resources Inventory (Cottage Grove Natural Resource Inventory
1998), MnDNR Public Water Inventory (PWI) Maps, and the Minnesota Land Cover and Classification System
(MLCCS). There are four MnDNR public water wetlands located in the project area (82W-Gables Lake, 83W-Unnamed
wetland, 84W-Unnamed wetland, and 87W-Regional Park Lake). The wetlands that are present within the project area
are depicted on Figure 10-2. These wetlands provide habitat for numerous waterfowl, amphibians, reptiles, and upland
wildlife species. Several species of migratory birds (ducks, geese, and cranes) commonly use wetlands.
Only one of the residential subdivisions that developed since the adoption of the AUAR had a wetland identified
during the required wetland delineation reports that were completed as a part of the development process. That
project was The Waters at Michaels Pointe, which is adjacent to a deep, open water marsh that is one of the few
natural wetlands in Cottage Grove that is of a considerable size. This designated wetland (now named Lake
Robert) was protected during construction in accordance with the requirements of Minnesota DNR and the
South Washington Watershed District. The Watershed District has this wetland identified as Protect 1 which
requires a 100-foot wide average wetland buffer. There were no other non-residential developments that had a
wetland identified or impacted.
Subsequent projects with wetlands have been delineated and impacts have been avoided or mitigated as required
by the South Washington Watershed District, who is also the LGU.
Watercourses
The City of Cottage Grove, MLCCS, MCBS, Metropolitan Council, and MnDNR information was used to classify and
map woodland areas. Cottage Grove Ravine Creek is a watercourse that runs through the project area and a portion of it
is a MnDNR public water. The portion that is a MnDNR public water starts just north of 80th Street and flows south
through Neighborhood 2. There are approximately 143,000 linear feet of watercourses within the project area. In
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general, watercourse corridors provide habitat for upland wildlife and migratory birds. Migratory birds, amphibians,
reptiles, and waterfowl are common types of species found along creeks.
The only impact to the reported watercourse was that additional public drainage and utility easements were
acquired over a portion of the creek in Section 23 as a part of a minor subdivision that was a component of the
acquisition of parkland by Washington County. In 2017 the SWWD completed a stream bed stabilization project
within the Cottage Grove Regional Park in conjunction with the stormwater overflow outlet construction project.
Lakes
The City of Cottage Grove, MLCCS, MCBS, Metropolitan Council, and MnDNR information was used to classify and
map woodland areas. Gables Lake and Regional Park Lake are both located within the project area and are both
identified by the MnDNR PWI map as public water wetlands (82W and 87W, respectively). Gables Lake and Regional
Park Lake account for the approximately 26 acres of lakes within the project area. Lakes provide habitat for migratory
birds, fish, waterfowl, amphibians, and reptiles.
Gables Lake is upstream of all development that occurred in the East Ravine. The Regional Park Lake is
downstream from the Washington County Government Center and the New Cottage Grove City Hall that were
constructed since the approval of the AUAR. This water body was not compromised by these two projects as the
sites were developed with surface water rate and quality controls that were constructed in accordance with the
South Washington Watershed Districts standards and requirements and
plan.
Woodland Areas
Woodland areas comprise approximately 27 percent of the total project area, accounting for an estimated 1,094 acres.
Several forest stands are found throughout the project area while others align the Cottage Grove Ravine Creek corridor.
Similar to agricultural/open lands, the woodlands provide habitat areas to numerous wildlife species described above.
The City of Cottage Grove, MLCCS, MCBS, Metropolitan Council, and MnDNR information was used to classify and
map woodland areas. The forest cover classifications within the project area are depicted on Figure 10.3, Natural
Resources. The majority of the woodlands were classified as oak forest and oak woodland/brushland. The City of
Cottage Grove had a natural resource inventory completed for the city in 1998 and the information is summarized below
for the project area.
The residential and commercial developments that occurred in the East Ravine since the adoption of the AUAR
were subject to the submission and review of tree preservation inventories. In instances when tree removal related
to development consistent with the 2030 Land Use Plan was in excess of ordinance criteria, the projects were
subject to tree replacement or cash mitigation approval conditions.
11.a.1.4.1 Neighborhood 1 (North) Natural Communities
Neighborhood 1 (north) is located north of 70th Street South and south of Military Road. Just north of 70th Street South
is a fairly large (117 acre) oak forest. This area has been logged in recent years. Oaks are the dominant tree species, but
a much greater proportion of the canopy is made up of other tree species such as aspen (Populus tremuloides), butternut
(Juglans cinerea), black cherry (Prunus serotina) , hackberry (Celtis L.), and bitternut hickory (Carya nutt). The shrub
layer is dominated by buckthorn (Plantago aristata).
Just north of this large oak forest is a mature oak forest. According to Constance Otis, this area was last logged during
the late 1800s. Since then, the canopy has recovered and today is dominated by white oak (Quercus alba) and bur oak
(Quercus macrocarpa) with a good diversity of other species in the subcanopy including bitternut hickory, butternut,
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basswood (Tilia linden), red oak (Quercus borealis), and hackberry. There are also scattered sugar maple (Acer
saccharum) and red maple (Acer rubrum) in this community. The shrub layer is fairly diverse containing elderberry
(Sambucus canadensis), chokecherry (Aronia medikus), and several species of currant and pagoda dogwood (Cornus
alternifolia). The ground cover is very diverse containing such species as jack-in-the-pulpit (Arisaema triphyllum),
(Circaea L.), bloodroot (Sanguinaria L.), and several species of ferns including sensitive and
maidenhair fern (Adiantum pedatum). Unfortunately buckthorn has invaded this community and will likely become
dominant in the future.
11.a.1.4.1 Neighborhood 1 (North) Natural Communities
Neighborhood 1 (north) is located north of 70th Street South and south of Military Road. Just north of 70th Street
South is a fairly large (117 acre) oak forest. This area has been logged in recent years. Oaks are the dominant tree
species, but a much greater proportion of the canopy is made up of other tree species such as aspen (Populus
tremuloides), butternut (Juglans cinerea), black cherry (Prunus serotina), hackberry (Celtis occidentalis), and
bitternut hickory (Carya cordiformis). The shrub layer is dominated by buckthorn (Rhamnus cathartica). Just north
of this large oak forest is a mature oak forest. According to Constance Otis, this area was last logged during the late
1800s. Since then, the canopy has recovered and today is dominated by white oak (Quercus alba) and bur oak
(Quercus macrocarpa) with a good diversity of other species in the subcanopy including bitternut hickory, butternut,
basswood (Tilia americana), red oak (Quercus rubra), and hackberry. There are also scattered sugar maple (Acer
saccharum) and red maple (Acer rubrum) in this community. The shrub layer is fairly diverse containing elderberry
(Sambucus canadensis), chokecherry (Prunus virginiana), and several species of currant and pagoda dogwood
(Cornus alternifolia). The ground cover is very diverse containing such species as jack-in-the-pulpit (Arisaema
triphyllum), (Circaea lutetiana), bloodroot (Sanguinaria canadensis.), and several species of
ferns including sensitive and maidenhair fern (Adiantum pedatum). Unfortunately, buckthorn has invaded this
community and will likely become dominant in the future.
The Dodge Nature Center became the owners of this property in 2013 and has already begun a buckthorn
management program.
A wetland is located west of this mature oak forest. The majority of this wetland consists of a deep, open water marsh.
Along the edges of the wetland, species such as sedge, cattail, rice cutgrass (Leersia oryzoides), river bulrush (Scirpus
fluviatilis), and blue flag iris (Iris versicolor), dominate. Within shallow areas along the wetland edge, there are
numerous mudflats containing plantain, cow parsnip (Heracleum lanatum), broad-leaved arrowhead (Sagittaria
latifolia), and marsh fern (Thelypteris palustris). These same species, along with cattail, are also present on several
floating bog mats. Submergent plants and floating leaf species such as yellow water lily (Nuphar lutea) and duckweed
(Lemna minor) are present in many open water areas of the wetland. Invasion by reed canary grass (Phalaris
arundinacea) and buckthorn has occurred along much of the wetland margin. However, these species have not moved
much beyond the wetland edges.
Just west of this large wetland is a small, shallow, open water/emergent marsh, containing many of the same species
found in the large wetland. Some of the common species include lake sedge (Carex lacustris), blue flag iris, plantain
(Alisma subcordatum), and broadleaf arrowhead. At the time of the original survey, this wetland contained only a small
pool of water in its center. Buckthorn has encroached into the wetland margin.
A degraded wet meadow dominated by reed canary grass is located east of the large wetland. This area appears to have
been farmed at one time.
The rest of Neighborhood 1 (north) consists of farm/agriculture land except for two small areas on the north side of
Military Road. One area is a conifer plantation dominated by scotch pine (Pinus sylvestris) with boxelder (Acer
negundo) and trembling aspen mixed along the plantation edges. West of this conifer plantation is an old field
dominated by introduced grasses such as smooth brome (Bromus ciliatus), bristly foxtail (Setaria spp.), and kentucky
bluegrass (Poa pratensis).
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A wetland is located west of this mature oak forest. The majority of this wetland consists of a deep, open water marsh.
Along the edges of the wetland, species such as sedge, cattail, rice cutgrass (Leersia oryzoides), river bulrush
(Schoenoplectus fluviatilis), and blue flag iris (Iris versicolor), dominate. Within shallow areas along the wetland
edge, there are numerous mudflats containing plantain, cow parsnip (Heracleum lanatum), broad-leaved arrowhead
(Sagittaria latifolia), and marsh fern (Thelypteris palustris). These same species, along with cattail, are also present
on several floating bog mats. Submergent plants and floating leaf species such as yellow water lily (Nuphar lutea)
and duckweed (Lemna minor) are present in many open water areas of the wetland. Invasion by reed canary grass
(Phalaris arundinacea) and buckthorn has occurred along much of the wetland margin. However, these species have
not moved much beyond the wetland edges. Just west of this large wetland is a small, shallow, open water/emergent
marsh, containing many of the same species found in the large wetland. Some of the common species include lake
sedge (Carex lacustris), blue flag iris, plantain (Plantago major), and broadleaf arrowhead. At the time of the
original survey, this wetland contained only a small pool of water in its center. Buckthorn has encroached into the
wetland margin.
A degraded wet meadow dominated by reed canary grass is located east of the large wetland. This area appears to
have been farmed at one time. The rest of Neighborhood 1 (north) consists of farm/agriculture land except for two
small areas on the north side of Military Road. One area is a conifer plantation dominated by scotch pine (Pinus
sylvestris) with boxelder (Acer negundo) and trembling aspen mixed along the plantation edges. West of this conifer
plantation is an old field dominated by introduced grasses such as smooth brome (Bromus ciliatus), bristly foxtail
(Setaria spp.), and Kentucky bluegrass (Poa pratensis).
The residential development that occurred in Neighborhood 1 did not impact the Dodge Nature Center Property
which is protected by a land conservation easement or any of the identified wetlands. In 2013, the Minnesota List
of Endangered, Threatened and Special Concern Species was amended to include butternut (Juglans cinerea)
11.a.1.4.2 Neighborhood 1 (South) Natural Communities
Neighborhood 1 (South) is located north of Highway 61 and west of County State Aid Highway (CSAH) 19. This area
contains low to moderate quality, dry, sand gravel prairie and some old fields now grown over with trees, shrubs, and
grasses. Wildlife values for this area were rated as low due to the lack of natural community diversity and poor
connectivity to other natural areas.
The few communities that exist in this area are all located near the intersection of Highway 61 and CSAH 19A. One
community is an old field dominated by introduced graminoids (grasses) and weedy forbs. Common graminoids include
smooth brome and Kentucky bluegrass. Common forbes include common milkweed (Asclepias L.), daisy fleabane
(Erigeron strigosus), spotted knapweed (Centaurea maculosa), and goatsbeard (Tragopogon pratensis). This field was
probably cultivated in the recent past.
East of the old field is a young mixed hardwood forest dominated by boxelder, green ash (Fraximus pennsylvanica), and
Chinese elm (Ulmus parvifolia). Both the shrub and ground cover layer contain mostly exotic and/or weedy shrubs and
herbaceous plants. The shrub layer is dominated by buckthorn, the ground layer by wood nettle (Laportea Canadensis)
and Virginian stickseed (Lappula redowskii).
East of the drive in movie theatre is a dry prairie occurring on a very doughty site with numerous areas of exposed fine
sand. In general, Kentucky bluegrass and smooth brome dominate this site. Where the site contains exposed sand, small
patches of little bluestem (Andropogon scoparius) along with a fair diversity of dry prairie forbs occur. Some of the
more common forbs include whorled milkweed, daisy fleabane, common milkweed, flowering spurge (Euphorbia
corollata), sulfer cinquefoil (Potentilla recta), and thimbleweed (Anemone patens).
A poor quality dry prairie almost completely overgrown by woody vegetation and leafy spurge is located east of the dry
prairie.
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A mixed hardwood forest that contains mostly non-native and/or weedy tree species and shrub and ground cover species
is located south of the drive-in movie theater.
The rest of the Neighborhood 1 (south) consists of farm/agriculture land.
The 23.5-acre Walmart development is located in the Cottage View area west of the former drive-in theatre site.
As a component of that project, there was tree removal and grading of the Walmart site and the western half of
the former drive-in site now referenced as the Apache Parcel. A tree inventory and mitigation plan were
e Preservation Ordinance for this project. The City Forester reviewed
the plan for accuracy and conformance. Tree mitigation fee of $148,000 was required as per the ordinance and
collected with the building permit for Walmart. This fee was placed in the CiInitiative
Fund, which is designated for landscape improvements in major transportation corridors, trailway corridors, and
park and open space areas. The balance of the former drive-in site has been continuously graded under the
guidance of an Interim Conditional Use Permit as the property owner prepares the site for a more suitable
development topography.
11.a.1.4.3 Neighborhood 2 Natural Communities
Neighborhood 2 is located north of Highway 61 and east of CSAH 19. As a whole the natural resources in the area
consists mainly of dry oak forest, mesic oak forests, and conifer plantations. Historic items such as the historic Dr.
William Fured for its eclectic
Century German immigrants.
The northern area of Neighborhood 2 consists of woodland-brushland, dry oak savanna, mesic oak forest, basswood
forest, and maple forest. In addition, this area also contains a small lake and a wetland. The diversity of different natural
communities is high.
Oak forests along with a variety of other community types including conifer plantation and lowland hardwood forest
dominate the central area of Neighborhood 2.
The southern area of Neighborhood 2 consists mainly of mesic and dry oak forests. This area also includes several
small dry, sand gravel prairies, a wet meadow/fen wetland, and a number of conifer plantations.
The only development activity that occurred in Neighborhood 2 was the construction of the Washington County
South Service Center and the Cottage Grove City Hall/Public Safety facility, and the realignment of 70th Street
(CSAH 20) which Washington County is in the process of completing. This realignment project only impacted
the built environment along the corridor and active agricultural fields. The government campus projects
contain rain gardens, native plantings, prairie, and Oak Savannah restorations. The end of 2019 brought the
completion of the HERO Center, which is a public safety training facility located on 85th Street in the northern
portion of the civic campus identified in the East Ravine Planning Area.
11.a.1.5 Grassland/Shrubland and Lawn/Landscaping
The City of Cottage Grove, MLCCS, MCBS, Metropolitan Council, and MnDNR information was used to classify and
map grassland/shrubland and lawn/landscaping areas. Grassland/shrubland and lawn/landscaping comprise
approximately 13 percent of the total project area, accounting for 513 acres. Grassland/shrubland and
lawns/landscaping within the project area are depicted in Figures 10.3A and 10.3B, respectively. Similar to
agricultural/open lands, the grassland/shrubland and lawn/landscaping areas provide habitat to numerous wildlife
species described above.
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No areas of grassland/shrubland were disturbed beyond the areas identified as development area within the
original approved East Ravine Master Plan. Areas developed as residential will have lawn and landscaping
areas established as they develop. In addition to front boulevard trees and corner trees, the City requires two
deciduous trees, two coniferous trees, and ten shrubs to be planted at every home constructed on a lot in the
East Ravine Planning Area as well as citywide.
11.a.1.6 Agricultural/Other Transitional Land
The City of Cottage Grove, MLCCS, MCBS, Metropolitan Council, and MnDNR information was used to classify and
map woodland areas. Agricultural/other transitional land comprises the largest portion of the entire project area,
accounting for 2,076 acres, approximately 52 percent of the project area. The agricultural/other transitional is defined as
agricultural land, undeveloped land, and land that was not classified during the biological inventory of the area and is
not differentiated from cropland. Some overlapping of other land types already described are included in this area.
The agricultural/other transitional areas provide nesting habitat, cover, and food for wildlife. There are numerous small
and medium sized mammals that utilize these lands including white-tailed deer, raccoons, red and gray fox, woodchuck,
squirrel, and other small mammals. Song and game birds may also be present throughout the project area and include a
variety of edge, open, and woodland species.
No areas of Agricultural or Transitional lands were disturbed beyond the areas identified as development areas
within the original approved East Ravine Master Plan.
11.a.1.7 Impervious Surfaces
The City of Cottage Grove, MLCCS, MCBS, Metropolitan Council, and MnDNR information was used to classify and
map impervious surface areas. Impervious surface areas comprise approximately 220 acres of the project area, primarily
roadways, parking areas, and buildings associated with development.
The statements in this section remain unchanged.
For residential developments in the East Ravine, it is estimated that 33 percent of developed areas are impervious
surfaces. The surface water management plan for each project specifies a tailored strategy for the capture and
treatment of surface water impacted by housing construction and associated impervious land cover.
11.a.1.8 Proposed Development
The proposed development pattern seeks to preserve a significant portion of the project area as park or open space area.
Approximately 1,580 acres or just over 41% of the project area is in some form of green space as itemized in Table 11.1.
The four 21 approved subdivisions that have occurred since 2006 are consistent with the East Ravine Master
Plan. In addition, the City worked with Washington County in the expansion of the Ravine Regional Park along
Kimbro Avenue. The acquisition financing of the new parkland was a component of the negotiated agreement
relating to the offset of regional parkland utilized for the Civic Campus. Consistent with the modifications in
land use and land cover through development, the preservation of open space within the East Ravine is not
actively quantified due to a lack of purpose as development occurs within the scope of approved land use plans
within the planning district.
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Table 11.1 - Open Space/Green Land Uses in the Development Scenario
The park and open space development that has occurred to date is in significant conformance with the green
space identified in Table 11.1 and the correlating areas found on the 2030 and 2040 Land Use Plans, the future
park and open space plan, and Figure 6.1 of this document. The statements in this section remain unchanged.
11.a.1.9 Potential Habitat Impacts
The conversion of open land, agricultural land, woodland, grassland, shrub land, and wetlands to urban types of
development will disturb the habitat and feeding areas and affect current wildlife species. Increased runoff volumes
during construction and from developed areas will drain to wetlands and creeks in the area (see the response to
Questions 16 and 17). Presently, development and infrastructure design plans are largely unknown for properties within
the project area. Due to the unknown nature of future development within the project area, the extent of impacts on
wildlife and natural resources is not fully known. Alternative site design to help to maintain areas for natural habitat are
supported by the subdivision design policies as identified in the
help to maintain areas for natural habitat.
The statements in this section remain unchanged.
The statements in this section remain unchanged.
11.b.1 Natural Heritage Program
The MnDNR NHP, data was obtained from the MnDNR and is included in Figure Natural Resources. In addition, the
City of Cottage Grove also purchased the electronic database containing NHP data from the MnDNR to review for the
AUAR.
There is one natural heritage recorded wildlife species and one recorded plant species that occur within the project area,
turtle (state listed threatened) and Kitten-tails (state listed threatened). There are no state listed
endangered species recorded for the project area.
In addition, the MnDNR NHP database has two recorded natural communities that occur within the project area, the Dry
Prairie (Southeast) Sand-Gravel Subtype and the Mixed Emergent Marsh (Prairie). These natural communities are
recorded in the NHP database because they are uncommon but are not protected by State or Federal laws.
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The natural communities and the species referenced in this section were not impacted by the development that
occurred since the adoption of the AUAR.
Minnesota Department of Natural Resources (DNR) Division of Ecological & Water Resources reviewed data
contained in the Natural Heritage Information System (NHIS; ERDB 20210043). The review identified ecologically
significant areas, providing recommendations to avoid or minimize impacts to the areas of concern. The review also
identified state and federally listed species and specified measures that must be taken prior to and during
construction. These comments are summarized in the paragraphs below, included in full in Appendix 13 and
supplemented by Figure 10.1, depicting future land use and areas of concern.
Threatened & Endangered Species
Rusty Patched Bumble Bee (Bombus affinis)
The rusty patched bumble bee (RPBB) is a federally listed endangered species. The U.S. Fish & Wildlife Service
(FWS) maps the
RPBB was historically present within the township. Most development related to the AUAR would convert
agricultural areas, which historically degraded RPBB habitat. In existing agricultural areas, future land conversion
may provide cultural vegetation for RPBB foraging.
Limited conversion of woodland may take place northwest of 70th Street and Jamaica Avenue (see. 11.a.1.4.1). This
woodland likely represents suitable habitat (e.g. wintering and spring foraging) within the AUAR study area. Given
the FWS probability mapping, a non-federal project does not require consultation pursuant to federal regulations. If
development becomes federalized, then consultation may be needed. In absence of a federal trigger, the City may, at
its discretion and after publication of revised Voluntary Guidance for Incidental Take Permits of the RPBB, enter
into voluntary consultation.
Loggerhead Shrike (Lanius ludovicianus)
Loggerhead shrike is a state-listed endangered species known to occur near the AUAR study area. This species may
occur in a variety of natural and cultural settings. The DNR advises avoiding clearing trees and shrubs from April
through July. If clearing takes place within that window, the DNR may require a nest survey prior to construction.
Kitten-tails (Besseya bullii)
Kitten-tails is a state-listed endangered species documented within areas designated for future park/open space which
will not be converted. Small portions of suitable habitat within Sections 11 and 22 of the AUAR study area (e.g.
savanna, prairie, and woodland) may be converted. If future improvements propose to convert this land, then
additional coordination will take
i)
-listed threatened species documented within the AUAR study area. DNR requires
avoidance measures contained in full within Appendix 13, and summarized below:
Avoid certain wetland and stream impacts between October 15 and April 15
Erosion control blankets shall only consist of bio-netting or natural netting, and not plastic-containing
products
Avoid mulch and revegetation products augmented with synthetics
Monitor for turtles during construction and report sightings to DNR
Species of Concern
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-listed species of concern. These
species are not afforded formal protection under the law; however, the City understands the avoidance measures
recommended for Loggerhead shrike to limit potential incidental disturbance to these species.
Ecological Areas
Multiple native vegetation communities and areas with biodiversity significance rated as moderate significance or
below significance are present within the AUAR study area. The area of biodiversity significance and native habitat
community located northwest of 70th Street and Jamaica Avenue (see 11.a.1.4.1) may be converted in part by the
development scenario. The Local Government Unit considering wetland impacts, if applicable, may need to consider
the status of these lands in deciding whether a project subject to the Wetlands Conservation Act will permanently
adversely affect a rare natural community, and, therefore if a wetland impacts must not be permitted.
11.b.1.1
(Emydoidea blandingii) is a state-listed threatened species associated with sandy soils and a
variety of wetland types. A species is ranked as threatened, if the species is likely to become endangered within the
foreseeable future throughout all or a significant portion of its range. Threatened species are protected under the Federal
Endangered Species Preservation Act of 1973, as amended in 1978, 1982, and 1988; Minnesota Statutes Chapter
84.0895; Minnesota Rules Chapter 6134.
c vegetation and sand uplands for
nesting. Studies by Congdon et.al. (1983) in Michigan and by Linck in Massachusetts have shown that nesting females
may travel considerable distances (200 to 400 meters) to a nesting area, passing enroute what appears to be suitable
nesting habitat immediately adjacent to the marsh in which they reside (Coffin and Pfannmuller 1988).
The loss of wetland habitat
through drainage or flooding to convert wetlands into ponds or lakes, loss of upland habitat through development or
conversion to agriculture, human disturbance (including collection for pet trade, road kills during seasonal movements),
and increases in predator populations (skunks, raccoons, etc.) that prey on nests and young all contribute to a decline in
this species.
In long-lived species, protecting the adults is critical to any conservation strategy. A female turtle may produce as many
as 500 eggs during her life. Losing many of these long-lived females, through habitat loss or direct mortality, would
seriously jeopardize the ability of a population to maintain itself. One of the potential threats is mortality while crossing
roadways. Roadway design and large culverts or tunnels may provide an alternative route for turtles, but requires further
evaluation to refine design and effectiveness (Lang 2000).
The species referenced in this section were not reported to have been impacted or potentially impacted by the
development that occurred since the adoption of the AUAR.
The statements in this section remain unchanged.
11.b.1.2 Kitten-Tails
The Kitten-tail (Besseya bullii) is a state-listed threatened plant species. A species is ranked as threatened, if the species
is likely to become endangered within the foreseeable future throughout all or a significant portion of its range.
Threatened species are protected under the Federal Endangered Species Preservation Act of 1973, as amended in 1978,
1982, and 1988; Minnesota Statutes Chapter 84.0895; Minnesota Rules Chapter 6134.
The Minnesota Kitten-tail populations are largely restricted to the bluffs and terraces of the St. Croix, Mississippi, and
Minnesota River valleys, specifically where the three rivers converge in the Twin Cities area. The plants prefer gravelly
soil in dry prairies, savannas, and open woods (Coffin and Pfannmuller 1988).
The Kitten-tail is quite distinctive and bears no close resemblance to any other species encountered in Minnesota. It is
characterized by a dense spike of sessile, yellowish flowers, each with two long exerted stamens. The basal leaves are
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large and heavily veined. The stem leaves are small and alternate and partially clasp the stem. The plants flower early in
the spring, but the spike and the basal leaves remain visible throughout most of the summer (Coffin and Pfannmuller
1988).
The kitten-tails that were identified within the East Ravine development area were located within the borders of
the Cottage Grove Regional Park, so no negative impact occurred as a result of the development that occurred
within the planning area.
The statements in this section remain unchanged.
11.b.1.3 Other Information
U.S. Fish and Wildlife Service (USFWS) resources indicate that the bald eagle (Haliaeetus Leucocephalus
roseroot (Sedum integrifolim spp. Leedyi), and prairie bush clover (Lespedeza leptostachya) are listed as federally
threatened in Minnesota and documented to occur in Washington County. However, there are no records indicating that
these species occur within the project area. Given the location and type of activity proposed, the USFWS determined
that the project is not likely to adversely affect any federally listed or proposed federally threatened or endangered
species or adversely modify their critical habitat. This precludes the need for further action on this project as required
under Section 7 of the Endangered Species Act of 1973.
The statements in this section remain unchanged.
The statements in this section remain unchanged.
12. P HYSICAL IMPACTS ON WATER RESOURCES
There will be no physical impacts on water resources within the project area. Section 2 of the Surface Water
Management Plan (SWMP) describes the water resources within the City, discussing the watersheds, land uses,
groundwater, and key water resources.
13. W ATER U SE
Based on information obtained from existing water supply studies and consultation with City engineering consultants at
Bonestroo Rosene Anderlik and Associates (now Stantec), the existing water supply and treatment for the East Ravine
area will be provided off site. In addition, the existing well field is felt to be adequate for the needs that will be
generated by the development scenario envisioned for the East Ravine area. The proposed East Ravine plan would
increase the water demand by approximately 13.0 Million Gallons per Day. Appendix 1 contains a technical
memorandum titled Cottage Grove East Ravine Planning Study: Watermain prepared by Howard R. Green Company in
February of 2005. This memo provides the methodology and details concerning impacts on future water usage for the
project area. Figures illustrating the water systems are included in Appendix 1.
Contact inquiries in relation to this study are to be directed to Stantec.
watermain improvements within the East Ravine. This plan continues to be used as a guide for new development
and is included in Appendix 1A. Figures illustrating the water systems are also included in Appendix 1A.
14. W ATER-RELATED L AND U SE M ANAGEMENT D ISTRICTS
There are no water related land use management districts that are impacted by the project. The Surface Water
Management Plan (SWMP) has been included as Appendix 5A and describes land and water resources for the City
of Cottage Grove, including wetlands and districts within the East Ravine area.
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The statements in this section remain unchanged.
15. W ATER SURFACE USE
There are no recreational water bodies in the project area. Section 2.5 of the Surface Water Management Plan
(SWMP) describes the key water resources within the City including the wetlands, lakes, draws, ravines, streams, and
the Mississippi River, and is included as Appendix 5A.
The statements in this section remain unchanged.
16. E ROSION AND SEDIMENTATION
Normal grading practices associated with urban development will be associated with future development in the Cottage
Grove East Ravine. Certain areas where topographic relief is dramatic have been placed in an open space or green land
use pattern to minimize potential for erosion and sedimentation problems. Best management practices will be applied to
all construction projects in the area to prevent erosion and sedimentation during construction projects. Section 7.2.1 of
required by the NPDES MS4 Permit.
The statements in this section remain unchanged.
17. W ATER Q UALITY-STORMWATER RUNOFF
Stormwater management was studied at depth for the Cottage Grove East Ravine project. A detailed analysis of
stormwater issues and plans is provided as Appendix 5 to this AUAR. The report analyzes existing stormwater systems
and drainage patterns as well as site characteristics that would promote environmentally friendly storm water
management practices. Figure 17.1 illustrates the existing storm water management system which uses a series of
existing small swales and depressions. The area is favorable to infiltration due to the sandy soils and significant depth to
groundwater or bedrock.
The stormwater management goal for this project is to utilize the natural drainage and infiltration capabilities of the
existing land. Stormwater management areas along planned parkways (as illustrated in Figures 6.1 and 17.2 will be
utilized to collect, infiltrate and direct overflow of runoff from adjacent neighborhoods. Overflow from the parkway
stormwater basins will be directed to larger natural infiltration basins which have the capacity to infiltrate all the runoff
from a 100-year storm event. Emergency overflow from the larger infiltration basins for events greater in intensity than
a 100-year event could be provided either through the existing Cottage Grove drainage system and/or through the future
regional stormwater conveyance system being planned by the South Washington Watershed District. The future
stormwater management system is illustrated in Figure 17.2 .
The statements in this section remain unchanged.
Updated storm water system information is provided in Appendix 5A, 2019 Surface Water Management Plan
future stormwater management systems.
18. W ATER Q UALITY-W ASTEWATER
A detailed analysis of sanitary sewer infrastructure systems and wastewater generation was conducted for this project.
The analysis is included as Appendix 2, a Technical Memorandum from Howard R. Green Company titled Cottage
Grove East Ravine Planning Study: Sanitary Sewer dated February of 2005.
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The City of Cottage Grove has a Comprehensive Sewer Policy Plan that was completed in May of 1992 (1996 Cost
and Rate Update) by Bonestroo, Rosene, Anderlik & Associates (now Stantec). The purpose of the Comprehensive
Sewer Policy Plan was to provide the City with an inventory of existing facilities and a guide for the expansion of
ment
of the public facilities plan for the Metropolitan Council and the Comprehensive Sewer Policy Plan (CSPP) for the
Metropolitan Waste Control Commission (MWCC). The Citymprehensive Plan Update included an updated
inventory of the sanitary sewer systems and projections for wastewater flows based on the updated future land use plan.
This update provided the data to assist the Metropolitan Council Environmental Services (MCES) in planning for the
now constructed Eagles Point Plant and the South Washington County Interceptor Sewer which will provide trunk
sanitary sewer facilities to the East Ravine area. This background data served as a starting point for the East Ravine
sanitary sewer analysis.
There are eight major sanitary sewer districts in the city of Cottage Grove, each defining the limits of service for a
separate trunk system. The East Ravine is in the Cottage Grove Ravine District (6,993 acres). This area is served by the
South Washington County Interceptor which will service the eastern 35% of Cottage Grove, the Central and Cottage
Grove Districts in Woodbury, and possibly other communities to the north in Washington County.
The treatment and disposal of wastewater occurs at the Cottage Grove Treatment Plant which is under the jurisdiction of
the MCES.
This preliminary sanitary sewer design for the East Ravine area (as detailed in Appendix 2) was accomplished in
accordance with Metropolitan Council Environmental Service (MCES) and Ten State Standards guidelines.
Construction plans for South Washington County Gravity Interceptor Phase 1 and South Washington County Gravity
Interceptor Phase 2 were used to determine the existing location of the trunk interceptor running along Keats Avenue
(CSAH 19). Existing sanitary stubs as indicated on the interceptor plans were utilized where possible. However, In order
to provide an efficient design some new connections to the interceptor are included in this preliminary plan. The study
area is primarily divided into two sections, Neighborhood 1 One located west of Keats Avenue and Neighborhood 2
Two located east of Keats Avenue. Design characteristics for each neighborhood are presented within Appendix 2.
Table 7-6 in Appendix 2B shows design flows for the ultimate system for sewer districts west of the MCES line.
Looking at the flows coming through and from the East Ravine area, Table 18.1 shows design flows based on the
2040 land uses for everything within the Cottage Grove Ravine Sewer District that flows into the MCES line. This
includes flows that originate outside of the East Ravine Area. Figure 18.2 displays the East Ravine boundary, sewer
districts, and nodes.
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Table 18.1 - Summary of Current and Future Residential Waste Generation Design Flows (MGD) for 2040
Land Use
The statements in this section remain unchanged.
sanitary sewer systems and projections
for wastewater flows based on the updated future land use plan and the South Washington Interceptor (the South
Washington Interceptor was not yet constructed when the original AUAR was prepared). This document is
included in Appendix 2A.
NOTE:
1. Sewer Districts were split according to flow areas and neighborhoods. (#) represents areas that were split between neighborhoods and/or the East Ravine
boundary. (1) represents areas within Neighborhood 1. (2) represents areas within Neighborhood 2. (3) represents areas outside of the East Ravine
boundary. (A) and (B) represent areas that had different flow areas and therefore the district was split for which direction flows went. These divisions are
shown on Figure 18.2.
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Future domestic wastewater flows were estimated for the East Ravine area based on a series of sub areas established for
Neighborhoods 1 and 2. The flows were based on the projected land uses as described in question 6 and illustrated in
Figure 6.1. Table 18.1 provides a summary of flows by each sub area. A map of the identified sub-areas and other
figures are included within Appendix 2. Table 18.2 displays the land uses within the East Ravine area based on
acreage, for sewer districts only within the boundary, as displayed in Figure 18.1. Table 18.3 shows flow rates based
on land use that are used to estimate flows. These rates are applied to the acreage of each district to calculate average
flows per land use by district, as displayed in Table 18.4. These average flows are then multiplied by a Met Council
Peak Flow Factor to determine the design flow per district. These design flows, specifically within the East Ravine
Area, are shown in Table 18.5, separated by neighborhood.
Table 18.2 East Ravine Area Future Land Use by District
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Table 18.3 Flow Rates
Table 18.4 East Ravine Area Average Flows
Table 18.5 East Ravine Area Design Flows
NOTES:
1. Districts CGR-12 and CGR-15 are divided between Neighborhood 1 and 2. Land use areas and flow rates were divided by acreage within each
neighborhood.
2. Average Flow does not account for flows outside of East Ravine Boundary.
3. Sewer Districts CGR-15, CGR-17 and CGR-20 are within the East Ravine Boundary, Neighborhood 2 but the flows flow outside of the boundary
and therefore are not included in this table.
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Based on the design flow calculations shown in Table 18.1 and Table 7-6 (in Appendix 2), the connections to the
MCES system were evaluated for any future upgrades to the City or MCES collection system for the development of
the East Ravine area. Based on the record plans from the MCES Interceptor project that was completed in 2002, the
S system was evaluated. By comparing the
capacities with the information in Table 18.5 and Table 7-6, and as shown in Table 18.6, the development of the East
the East Ravine
area will be analyzed per the capacities and built as development occurs.
Table 18.6 Capacity of MCES Connections
No new on-site systems are proposed to serve the East Ravine area.
The information in this table remains unchanged.
19. G EOLOGIC HAZARDS AND SOIL CONDITIONS
Most of the project area is located in a groundwater recharge area due to the predominantly sandy soils, underlain by
gravel and rock, which allows rapid percolation of water into the aquifer. Groundwater depth ranges from a shallow of
40 feet to upwards of 300 feet in places. The Prairie du Chien aquifer is located close to the surface and is accessed by a
limited number of rural homes for private well water. The Jordan aquifer is much deeper ranging in depth from 150 to
The bulk of the project area is classified as
bedrock. The areas of shallow bedrock are located on the western edge of Neighborhood 1 and in the central portion of
Neighborhood 2. Areas of shallow bedrock are most prominent east of Keats Avenue, and east of the project area.
Figure 19.2 illustrates the general depth to bedrock.
Sensitivity to Pollution: The Geologic Atlas (MGS 1989) maps the sensitivity to pollution of the water table aquifer. The
water table aquifer in the area is within the glacial material that consists of glacial till or outwash. The map indicating
assumptions and is to be used as a general gauge of the overall susceptibility
to pollution based on the travel time of pollutants from a surface source to the water table aquifer. A shorter anticipated
time of travel translates into a higher sensitivity rating for the aquifer. The majority of the East Ravine (and the entire
City of Cottage Grove) has a high susceptibility of groundwater to pollution.
A standard soils map is included as Figure 19.1. Soils are predominantly of a sandy loam nature, highly permeable with
relatively good agricultural suitability.
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The statements in this section remain unchanged.
The statements in this section remain unchanged.
20. S OLID WASTES; HAZARDOUS WASTES; STORAGE TANKS
A) Solid Wastes
The development scenario includes a mixture of residential and commercial uses. These uses will generate additional
municipal solid waste (MSW) and recycling products. Based on information provided by Dan Schoepke, Sr.,
Environmentalist for Washington County, estimates for MSW and recycling on a household and employee basis were
generated. These numbers are as follows:
Waste Generation 2012 2018
MSW per HH/year . 820 tons .606 tons
MSW per employee/year 1.407 tons . 582 tons
MSW recycled per HH/year 0.356 tons .582 tons
MSW recycled per employee/year 0.847 tons .670 tons
Estimates are based on the total household and employment projections for Washington County as of 2012 2018
(89,875 HH and 74,605 jobs) 96,424Households and 87,611 jobs and the total amount of MSW collected (178,673
tons) 117,017 tons recycled (32,023 tons of residential and 63,227 tons non-residential) (56,161 tons of residential
and 56,161 tons non-residential) in Washington County. An assumption was made that the total amount of MSW is
split 50/50 residential/commercial.
S OLID WASTES; HAZARDOUS WASTES; STORAGE TANKS
A) Solid Wastes
The development scenario includes a mixture of residential and commercial uses. These uses will generate additional
municipal solid waste (MSW) and recycling products. Based on information provided by Dan Schoepke, Sr.
Environmentalist for Washington County, estimates for MSW and recycling on a household and employee basis were
generated. These numbers are as follows:
MSW per HH/year 1.248 tons
MSW per employee/year 1.335 tons
MSW Recycled per HH/year 0.385 tons
MSW Recycled per Employee/year 0.757 tons
Estimates are based on the total household and employment projections for Washington County as of 2003 (77,456 HH
and 72,442 jobs) and the total amount of MSW collected (193,366 tons) and recycled (29,829 tons of residential and
54,803 tons non-residential) in Washington County. An assumption was made that the total amount of MSW is split
50/50 residential/commercial.
Cottage Grove East Ravine AUAR
Update Document November 2020
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Using the average waste and recyclables per household and employee, waste generation and recyclable materials were
estimated based on future development projections in the East Ravine. These numbers are presented in Tables 20.1 and
20.2.
Table 20.1 - Summary of Current and Future Residential Waste Generation
/ǒƩƩĻƓƷ ĻƭƷźƒğƷĻ CǒƷǒƩĻ
ƚŅ ğƭƷĻ 9ƭƷźƒğƷĻƭ ƚŅ
wĻƭźķĻƓƷźğƌ ğƭƷĻ DĻƓĻƩğƷźƚƓ źƓ CǒƷǒƩĻ ğƭƷĻ tĻƩ
DĻƓĻƩğƷźƚƓ wğƷĻƭ ƷƚƓƭ IƚǒƭĻŷƚƌķƭ ĻğƩ ΛźƓ ƚƓƭΜ
MSW/household/year 0.606 6,700 4060.2
Tons of Recycled Product
/household/year 0.036 6,700 241.2
Table 20.2 - Summary of Current and Future Non-Residential Waste Generation
/ǒƩƩĻƓƷ 9ƭƷźƒğƷĻ CǒƷǒƩĻ
ƚŅ ğƭƷĻ 9ƭƷźƒğƷĻƭ ƚŅ
bƚƓ wĻƭźķĻƓƷźğƌ ğƭƷĻ DĻƓĻƩğƷźƚƓ źƓ CǒƷǒƩĻ ğƭƷĻ tĻƩ
DĻƓĻƩğƷźƚƓ wğƷĻƭ ƷƚƓƭ 9ƒƦƌƚǤĻĻƭ ĻğƩ ΛźƓ ƚƓƭΜ
MSW/Employee/year 1.407 1,700 2391.9
Tons of Recycled Product /
employee/ year 0.847 1,700 1439.9
* Employment estimates based on project magnitude data of 850,000 square feet of commercial space at one employee per 500
square feet of space.
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Update Document November 2020
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The statements in this section remain unchanged.
The current waste generation information is included above and the future waste generation rates included in
table 20.1 and 20.2 remain unchanged.
B) Hazardous Wastes
No response required.
The statements in this section remain unchanged.
The statements in this section remain unchanged.
C) Storage Tanks
There are no specific locations for above or below ground storage tanks known at this time. If any business should need
above or below ground storage tanks, it would need to follow MPCA and other applicable standards and procedures.
The statements in this section remain unchanged.
The statements in this section remain unchanged.
21. Traffic
A detailed traffic study was completed and is included as Appendix 3. This traffic study provides an analysis of existing
traffic volumes, patterns and roadway characteristics for the East Ravine project area, provides analysis on impacts on
traffic that would be caused by the development scenario and offers mitigation measures in the form of roadway
improvements, intersection and signal adjustments and traffic management measures. The complete response to question
21 is referenced to the technical memorandum included as Appendix 3. This includes all figures illustrating existing
traffic/transportation systems and future traffic impacts.
A component of the Walmart commercial development included the completion of traffic studies that can be
referenced in appendix 11. Phase I of the infrastructure improvements recommended in these studies were
completed in 2013. Any significant additional commercial growth in this neighborhood will require Phase II of the
traffic improvements identified.
In 2017, the Phase II roadway improvements were completed in conjunction with the East Point Douglas Road
and Highway 61 roundabout traffic improvement construction project. The traffic study of East Point Douglas
Road and CSAH 19 is provided in Appendix 11.
A new version of Figure 3.5 (2020 ADT Volumes) from the 2005 traffic study in Appendix 3 has been provided to
incorporate future traffic projections fro2040 Traffic with
Ravine Parkway). As can be seen, traffic volumes in 2040 are generally projected to be less than originally thought
in 2020 per the 2005 study. Because of this, impacts due to traffic and noise are expected to be consistent with (if
not less than) the original studies of this AUAR.
22. V EHICLE-RELATED AIR EMISSIONS
For roadway projects, the two pollutants of concern are carbon monoxide (CO) and PM10. The EPA and the Minnesota
Pollution Control Agency (MPCA) do not require PM10 analysis. To assure that a project is not in violation of the
National Ambient Air Quality Standards (NAAQS), the need for an air quality analysis to address emissions of CO must
be determined.
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The East Ravine project is in Washington County, one of the Twin Cities seven-county metropolitan areas considered a
CO maintenance area. To determine the need for a hot-spot analysis, the Twin Cities has a screening method to compare
project locations to
one of these intersections, then it is presumed it will not cause any violations. There are three MPCA monitored
locations and seven top intersections (see Table 22.1). The East Ravine project area does not include any of these
locations.
Table 22.1 - Top Ten Intersections Twin Cities CO Maintenance Area
ID DESCRIPTION 1998 AADT*
Top 7 Intersections
1 TH 169 at CSAH 81 77,200
2 TH 101 at TH 7 65,000
3 TH 100 at CSAH 81 71,150
4 TH 10 at University Avenue 63,600
5 TH 252 at 85th Avenue 61,700
6 TH 252 at 66th Avenue 64,500
7 TH 252 at Brookdale Drive 58,550
3 MPCA Monitored Locations
8 University and Lexington Avenue 54,500
9 Snelling at University Avenue 57,750
10 Hennepin Avenue at Lake Street 35,800
ID DESCRIPTION 2007 AADT*
Top 7 Intersections
1 TH 169 at CSAH 81 79,400
2 TH 7 at TH 101 66,600
3 TH 252 at 85th Avenue 66,800
4 University Avenue at Snelling Avenue 59,700
5 TH 252 at Brookdale Drive 61,300
6 Cedar Avenue at County Road 42 75,100
7 TH 7 at Williston Road 54,900
3 MPCA Monitored Locations
8 University and Lexington Avenue 59,700
9 TH 252 at 66th Avenue 72,500
10 Hennepin Avenue at Lake Street 37,000
* Most current AADT available
ID DESCRIPTION 2020 AADT*
Top 7 Intersections
1 Cedar Ave. At County Rd 42 82,300
2 TH 252 at 66th Ave. 79,300
3 TH 252 at 85th Ave. 74,600
4 County Rd. 42 at Nicollet Ave. 71,400
5 TH 252 at Brookdale Dr. 68,100
6 TH 7 at County Rd. 101 60,000
7 TH 7 at Williston Rd. 54,900
3 MPCA Monitored Locations
8 University Ave. at Lexington Avenue
52,600
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9 University Ave. At Snelling Ave. 50,600
10 Hennepin Avenue at Lake Street 31,300
Note: University Ave. At Snelling Ave. is no longer being monitored by the MPCA
* Most current AADT available
The Table22.1 was updated with the latest figures from the MPCA.
The final screening criteria is whether the project roadways will have traffic levels in excess of the benchmark AADT
level of 77,200 79,400. The East Ravine project is not forecasted to have traffic levels this high. The results of the
screening procedure show that the East Ravine development project does not require a hot-spot analysis.
The statements in this section remain unchanged, but table 22.1 was modified as noted.
2002
AADT 2020 ADT 2040 ADT
Counts
Location
84,000
US 61
North of 70th Street 53,000 69,300
62,000
US 61
Between 70th Street and 80th Street 42,000 51,100
Between 80th Street and Keats
43,400
US 61
31,000 42,800
Avenue
Between Keats Avenue and Kimbro 44,400
US 61
26,000 32,700
Avenue
9,700
70th Street
Between US 61 and Jamaica Avenue 6,400 10,400
5,200
Between Jamaica Avenue and Keats
70th Street
2,200 10,100
Avenue
24,000
80th Street
Between US 61 and Hinton Avenue 22,300 28,000
17,100
80th Street
Hinton Avenue and Ideal Avenue 12,600 16,100
12,500
80th Street
Ideal Avenue and Jamaica Avenue 10,100 12,700
Between Jamaica Avenue and Keats
5,400
80th Street
7,400 9,300
Avenue
1,250
80th Street
Keats Avenue to Kimbro Avenue 1,200 6,600
Between Military Road and 70th 3,400
Jamaica Avenue
4,200 15,900
Street
7,500
Jamaica Avenue
Between 70th Street and 80th Street 7,400 10,500
19,500
Jamaica Avenue
Between 80th Street and US 61 11,200 17,700
13,100
Keats Avenue
North of Military Road 5,600 12,600
Between 70th Street and Military 13,100
Keats Avenue
7,600 12,600
Road
11,500
Keats Avenue
Between 70th and 80th Street 6,200 11,000
9,700
Keats Avenue
Between 80th Street and 90th Street 6,200 11,000
8,450
Keats Avenue
Between 90th Street and US 61 6,200 13,800
560
Kimbro Avenue
Between Lamar Avenue and US 61 500 4,000
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Between Ideal Avenue and Jamaica
2,550
Military Road
5,000 14,100
Avenue
Between Jamaica Avenue and Keats -
Military Road
1,450 -
Avenue
4,700
Military Road
Keats Avenue to Lamar Avenue 3,000 6,000
1,150
Lamar Avenue
70th Street to Kimbro Avenue 1,200 2,000
Source: Mn/DOT Year 2002 ADT Flow Maps and Howard R Green Company
23. S TATIONARY SOURCE AIR EMISSIONS
No response required.
The statements in this section remain unchanged.
Nearly all commercial and residential developments have potential to emit greenhouse gases (GHG) from various
sources. Project construction may emit GHG by releasing gases that build up in soils. Carbon dioxide (CO2),
methane (CH4), and nitrous oxide (N2O) each build up in soils through plant life cycles and as organic material
decays. These gas traps release GHG when disturbed by processes such as agricultural production and excavation.
Project construction will use manufactured goods, the production of which likely relies upon energy developed from
GHG. Natural gas-fired combustion equipment emit relatively low levels of typical combustion emissions, such as:
Oxides of Nitrogen (NOx); Carbon Monoxide (CO); particulate matter (PM) and volatile organic compounds
(VOCs); and GHGs such as CO2, CH4 and N2O. Natural gas-fired equipment also emits low levels of hazardous air
pollutants (HAPs) that are normal constituents of combustion by-products.
Use of fossil fuels, refrigerants and electricity sourced in part from fossil fuels will continue throughout the expected
development lifetime. After construction, sustained use of the site will generate GHG. While the development of a
detailed GHG inventory is not possible because the final uses, tenants, buildings, construction materials and contents
have not been determined, residential and commercial tenants are anticipated to consume energy developed partly
from fossil fuels and may burn natural gas for activities such as heating, cooking or other production. Trips by fuel-
burning and electric vehicles relying on fossil fuel-sourced electricity will also generate GHG.
An estimate below of GHG production related to the project, providing general information on the scale of GHG
emissions, distinguishes between one-time emissions sourced from construction and annual emissions from onsite
use. It should be noted that the full GHG estimates for the Construction and Operational Phases would not occur
simultaneously in the same year. Construction GHG emissions will occur only during the relatively short
construction phases and will not continue into the Operational Phase. The two phases are evaluated separately as
they are not intended to be additive. These quantities represent an estimate of activities that may be reasonably
construed to be under the control of the City of Cottage Grove. Individual sources that exceed MPCA and EQB
thresholds for air permitting and environmental review may still be required to provide detailed analysis of site-
specific GHG emissions. Note that land uses will vary depending upon developer decisions. The exact inventory of
such natural gas-fired equipment is not yet known, because the final uses are speculative.
Table 23.1 Estimated Greenhouse Gas (GHG) Emissions
1
Annual Construction
Activity Metric Tons COe per Year
2
Off-Road Construction Vehicles 5,000
On-Road Construction Vehicles 6,600
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Construction Aggregates, Concrete and Hot Mix 14,4000
Asphalt
TOTAL CONSTRUCTION PHASE 26,000
Operation of Future Developments
Activity Metric Tons COe per Year
2
2
Residential 91,944
(inc. energy, waste disposal, 12,000 vehicle miles/household)
3
Commercial 46
4
Institutional 28
Estimated Annual GHG Emissions 92,018
NOTE:
1. Extrapolated from estimates of GHG emissions for mixed use construction at Central Commons, Stillwater, Minnesota. Assumes 80 acres of
construction/year. Excludes rural estate and park/greenspace.
2. ouseholds. Includes onsite energy
consumption, waste/recycling, and 12,000 vehicle miles per household
3. Calculated for typical businesses (assuming 4/acre of commercial land use and 1/acre of mixed use) using commercial CO2e calculator. Assumes
combination of big box, grocery/market, restaurant, and miscellaneous retail. Vehicle travel is captured by Residential data provided.
Minnesota Rule 7008.2600, subpart 1C for insignificant facility emissions in air permitting, and Minnesota Rule
4410.4300, subpart 15B for EAW preparation, each set a threshold of 100,000 Metric Tons CO2e for stationary
sources. As a whole, development scenario analyzed by the AUAR, near build out, appears to have potential to be
near or exceed thresholds for review of a single stationary source; however, those numbers typically are limited to the
operation of the facility (e.g. factory emissions) and do not typically include energy production, waste, vehicle miles,
and the other data presented here.
At this time, all of the above types of emission sources, in aggregate, do not typically trigger an air emissions permit
from MPCA for commercial and residential development projects. However, this determination can only be made
once proposed equipment inventories and estimated throughputs are known with reasonable certainty. The Project
Owner and/or Tenant(s) are responsible for making air permit applicability or exemption determinations prior to
starting construction. Such permit or exemption determinations would apply to direct stationary source emissions
resulting from equipment to be operated, and within certain sizes and throughput levels. Regardless of the timing of
this future air permitting determination, commercial and residential development projects of the type proposed here
do not typically trigger air permitting requirements. Based on the above information, the type and extent of stationary
source air emissions to be associated with the Project appear to be minor and are not expected to have the potential
for significant environmental effects.
The EQB is developing standards for evaluating GHG emissions for environmental review. In absence of additional
guidance, the project does not appear to have potential for significant GHG emissions.
24. D UST, ODORS, NOISE
Existing noise levels were measured at two locations in the project area. Monitoring locations represent undeveloped
lands expected to experience commercial and residential development or impacts from commercial and residential
development. The future Build alternative and associated traffic volumes expected in the year 2020 were modeled using
the Minnesota Department of Transportation traffic noise model, MINNOISE. Monitoring data and modeling results
were compared with the Minnesota Pollution Control Agency (MPCA) Noise Rules to evaluate traffic noise impacts and
recommend mitigation measures. Modeling results were used to create noise contours showing the location of the
residential daytime and nighttime L10 and L50 noise contour lines. L10 and L50 are sound levels in decibels (dBA) that
are exceeded in 10 percent or 50 percent, respectively, of the time for a one-hour survey.
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The statements in this section remain unchanged.
Existing Noise Levels
On March 3, 2005, noise monitoring was conducted at two locations in the project area. The purpose of the noise
monitoring was to document existing noise levels. Noise measurements were conducted in accordance with Minnesota
Rules Chapter 7030, Noise Pollution Control. The meteorological conditions were as follows:
Temperature - +2 degrees d
Humidity 76%
Wind Calm
Barometric Pressure
Table 1 summarizes the equipment Earth Tech staff used to collect monitoring data for this noise analysis.
Table 24.1 - Noise Analysis Instrumentation Summary
Instrument Make Model Calibration Date Serial Number
Dosimeter 1 Quest Q-300 2/28/05 at 114.0 dBA QC6030052
Dosimeter 2 Quest Q-30 2/28/05 at 114.0 dBA QC2921212
The monitoring sites were selected at locations where existing noise levels could not be modeled with MINNOISE or to
compare measured noise levels to modeled noise levels to confirm the validity of the model. The results of the noise
measurements at the monitoring locations are listed in Table 2 and the locations of the sites are indicated on Figures 2
and 3. MPCA maximum allowable daytime noise levels are 65 dBA for L10 and 60 dBA for L50. The maximum
nighttime noise levels are 55 dBA (L10) and 50 dBA (L50).
Table 24.2 - Nighttime Noise Monitoring Summary
Site Date Time Distance L10 L50 MPCA Exceeding
Sampled Sampled from CL (dBA) (dBA) Nighttime (Yes/No)
L10 L50
(dBA) (dBA)
Gordon and March 3, 6:00 am 150 feet 56 46 55 50 Yes
Bonnie 2005 to 7:00
Tank am
Property
Washington March 3, 6:00 am 600 feet 51 54 55 50 Yes
County 2005 to 7:00
Property am
The statements in this section remain unchanged.
Future Noise Levels
The traffic noise model analyzed the existing roadway network and proposed East Ravine Parkway. The Howard R.
Green Company supplied the existing traffic levels in 2003 and the predicted traffic levels in 2020. Earth Tech adjusted
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Update Document November 2020
Page 45
the 2003 traffic data to 2005 conditions. The Washington County Department of Transportation provided information
regarding truck percentages, speed limits, and nighttime peak hour volumes. Earth Tech used aerial orthographic
mapping to determine roadway alignments and digitized the existing and proposed roadway alignments for use in the
MINNOISE noise model. Keats Avenue, Kimbro/Lamar Avenue, Jamaica Avenue, 80th Street, 70th Street, and Military
Road were modeled in the for year 2005 and 2020 peak hour traffic. The proposed East Ravine Parkway was modeled
only for year 2020 peak hour traffic. The highest peak hour traffic volume (PHV) for each modeled roadway is shown in
Table 24.3.
The traffic stream in the MINNOISE model was determined to be 95% cars, 2% medium trucks, and 3% heavy trucks
for all roadways except Keats Avenue. The traffic stream for Keats Avenue was determined to be 93% cars, 3% medium
trucks, and 4% heavy trucks. Roadway speeds were modeled as follows:
d Keats Avenue 55 mph d
d Kimbro/Lamar Avenue 55 mph d
d Jamaica Avenue 45 mph d
d 80th Street 45 mph d
d 70th Street 45 mph d
d Military Road 55 mph d
d East Ravine Parkway 40 mph d
Table 24.3 - Peak Hour Traffic Volumes
Location Existing (2005) Predicted (2020)
Daytime* Nighttime* Daytime* Nighttime*
Keats Avenue
70th Street to Military Road 1000 750 1680 1260
Kimbro/Lamar Avenue
US 61 to Lamar Avenue 740 555 480 360
Jamaica Avenue
70th Street to Military Road 560 420 1510 1135
80th Street
Jamaica Avenue to Keats Avenue 760 570 980 735
70th Street
Jamaica Avenue to Keats Avenue 590 445 1520 1140
Military Road
Ideal Avenue to Jamaica Avenue 750 565 1090 820
East Ravine Parkway
80th Street to 70th Street N/A N/A 1190 850
*Daytime is defined to mean those hours from 7:00 am to 10:00 pm. Nighttime is defined to mean those hours from
10:00 pm to 7:00 am.
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Results
Modeling results are shown as contours on Figures 2 and 3 of Appendix 4. Traffic noise levels between the roadway
centerline and the contour line are predicted to exceed the corresponding MPCA Daytime L10 and L50 noise levels.
Table 24.4 shows the distances from roadway centerline to the noise contour.
Table 24.4 - Distance to Contours
Approximate Distance from CL in Feet
2005 MPCA Daytime 2020 MPCA Daytime
Location
L10 L50 L10 L50
(65 dBA) (60 dBA) (65 dBA) (60 dBA)
Keats Avenue (70th Street to Military Road) 197 164 262 262
Kimbro Avenue (US 61 to Lamar Avenue) 131 82 115 33
Jamaica Avenue (70th Street to Military Road) 262 203 197 190
80th Street (Jamaica Avenue to Keats Avenue) 108 69 135 85
70th Street (Jamaica Avenue to Keats Avenue) 115 59 152 150
Military Road (Ideal Avenue to Jamaica Avenue) 161 121 205 164
East Ravine Parkway (80th Street to 70th Street) N/A N/A 118 80
Residences located within the distances above, as measured from the roadway centerline, are predicted to experience
The Nighttime peak hourly volumes are approximately 75% of the Daytime peaks. Due to the nominal reduction in
traffic and the substantial reduction (10 dBA) of the allowable L10 and L50, the distance from the roadway centerline to
the nighttime noise contour is approximately 700 feet. At the present time, existing noise levels at monitored locations
exceed MPCA Nighttime criteria. The Tank monitoring site is located 150 feet north of 80th Street and exceeds the L10
during the 6:00 am to 7:00 am time period. The Washington County monitoring site is located 600 feet east of Keats
Avenue (CSAH 19) and exceeds the L50 during the 6:00 am to 7:00 am time period.
Mitigation
vels
near roadways in the project area. The City of Cottage Grove is required to comply with Minnesota Rules 7030.0030.
This statute requires municipalities to ensure that existing noise levels comply with state noise limits prior to occupants
moving into residences in the proposed development. Barriers such as earthen berms or landscaping can reduce traffic
noise levels. Increasing the distance between the source and the receiver also reduces traffic noise levels (i.e. larger
setbacks from arterial or collector roadways).
The information above continues to be valid. A component of the Walmart commercial development included the
completion of Noise Impact Study that can be referenced by contacting the City. Findings of the study indicated
that the planned commercial growth will not have a negative impact on the surrounding area. The City recently
adopted Ordinance No. 923, which modifies the way the City monitors and addresses noise complaints within the
community. The ordinance can be found on the www.cottage-grove.org
https://www.cottagegrovemn.gov/ No Change in Statement.
25. S ENSITIVE RESOURCES
A combination of existing resources and inventory reports were used to assess the impacts on sensitive resources in the
East Ravine Area. These resources included the Old Cottage Grove Historic District Preservation Planning Report
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Page 47
(Vogel 2002), Preservation Planning Report: Documentation Supporting the Nomination of the Military Road Heritage
Corridor to the City Register of Historic Sites and Landmarks ( Historic Preservation Division, Department of
Community Development, City of Cottage Grove, July 1999), the Comprehensive Plan (City of Cottage Grove, 2000),
the Comprehensive Plan (City of Cottage Grove, 2030) the Natural Resource Inventory (BRA, 1998), South
Washington Watershed District CD-P86 Natural Resource Management Plan (SWWD and EOR, 2002) and resource
information from the State Historic Preservation Office.
Archeological, historic and architectural resources
The most notable resources are the Comprehensive Plan, The Old Cottage Grove Historic District Preservation Planning
Report and the Documentation Supporting the Nomination of the Military Road Heritage Corridor on the City Register
of Historic Sites and Landmarks. These reports present documentation
preservation and supporting the nominations of the Old Cottage Grove Historic District and the Military Road Heritage
Corridor to the City Register of Historic Sites and Landmarks. The intent of historic district designation is to provide a
guide for future community development decision making that acknowledges need for change while providing
protection for historically significant buildings and sites. The report also contains a comprehensive inventory of all the
heritage resources within the district. Though the Old Cottage Grove Historic District and the Military Road Heritage
Corridor have they have not been nominated to the
National Register of Historic Places.
Old Cottage Grove is in the NW part of the City and extends roughly from 70th Street (CSAH 22) south along Lamar
Ave, including side streets, to 77th. The area is also known as Cottage Grove Village and East Cottage Grove. Most of
the land and buildings in the area are private property. Lamar Ball fields, Old Grove Community Park, and Fire Station
No.4 are publicly owned. The district has 9 sites of primary significance which are properties that have been
individually listed or eligible for nomination to the City Register of Historic Sites and Landmarks. There are also 42
sites of secondary significance. This category consists of properties more than fifty years old and that contribute to the
historic character of the district but lack individual distinction.
The village was platted with a linear plan and a clear distinction between the village and the surrounding countryside.
Expansion of the town was constrained by the northern limit of the Cottage Grove Ravine. The original 40 acre plat in
s core functions were located outside of
the plated area.
The heart of the historic district is Lamar Avenue, which is the old village main street. Traditional streetscape on Lamar
Ave includes little or no setback from the street and narrow side yards. Trees were planted to define property edges and
they continue to be one of the defining features of the district.
Today, Old Cottage Grove historic district is a mix of residential, commercial, funerary, religious and agricultural
buildings. Several preserved architectural landmarks represent Greek Revival, Italian Villa, Queen Anne, Arts and
Crafts, and Colonial Revival building styles. There are also modest homes built in the 19th and 20th Centuries.
Architectural features include: 1-2 story facades; low to medium pitch gable roof shapes; formal entrances; and one-
story porches. Most of the remaining buildings built prior to 1950 are residences as many of the non-residential
buildings have been razed or converted. Wood agricultural outbuildings, detached garages, and sheds also contribute to
Two properties are on the National Register of Historic Places. These include the Historic Mary and Cordenio
Severance House/Cedarhurst Mansion at 6940 Keats Avenue South and the John Furber House at 7310 Lamar Avenue
South. A number of additional sites have been placed on the City Register of Historic Sites. These locations are
illustrated in Figure 25.1.
No archeological surveys have been conducted within the historic district but there are several potentially significant
pioneer home, church, and school sites that need to be considered in development planning.
The Military Road Heritage Corridor through Cottage Grove is part of a larger historic military road that connected
Point Douglas with Fort Ripley. The Point Douglas and Fort Ripley Military Road resources is designated WA-CGC-
186 in the State Historic Preservation Office inventory database.
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The Military Road Corridor incorporates all of Lehigh Road and Military Road within the city limits and that part of
Lamar Avenue between Lehigh Road and 70th Street; CSAH 22 west of Lamar Avenue; and the abandoned roadway
segment west of Old Cottage Grove village in Section 11, Township 27 North, Range 21 West. Military Road was laid
out by the Federal government in 1851-1853. In 1914 it became a state aid road. The corridor was a popular place for
early settlement (mid to late 1800s) and has long been a major transportation corridor connecting south Washington
County to St. Paul and Minneapolis.
The Documentation Supporting the Nomination of the Military Road Heritage Corridor to the City Register of Historic
Sites and Landmarks contains a greater account of the historical significance of the corridor and should be referenced
for further details on the corridor.
Informational signage regarding the history of the Military Road/Trail Corridor was installed in conjunction with
the 2019 Ravine Parkway construction project.
The referenced areas continue to be identified as being
Places but have not been registered to date.
The statements in this section remain unchanged.
Prime or unique farmland
It is not anticipated that existing farmlands will be protected through special programs, deed restrictions, conservation
project area will be developed over time.
The statements in this section remain unchanged.
The statements in this section remain unchanged.
The 2014 East Ravine residential development, the 2013 East Point Douglas Road improvement project, and
the construction of the Ravine Parkway Civic Campus provided a key link in the local and regional trailway
system of south Washington County with the Cottage Grove Ravine Regional Park. Since the adoption of the
original AUAR, the Mississippi River Trail (USBR #45) was established and also provides a connection to the
region, state, and nation. http://www.mississippirivertrail.org/index.html . With the new residential
developments within the East Ravine, the City created several neighborhood parks developed that conform to
the East Ravine Park Master Plan.
Designated parks, recreation areas or trails
A major feature of the project area is the Cottage Grove Ravine Regional Park. This regional park provides an
abundance of passive natural areas, picnic areas and trail corridors. The development scenario for the East Ravine
project includes the addition of a number of park and open space features that provide connections to Cottage Grove
Ravine Regional Park. The park features include a variety of community and neighborhood parks with active and
passive play areas.
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The 2014 East Ravine residential development, the 2013 East Point Douglas Road improvement project, and the
construction of the Ravine Parkway Civic Campus provided a key link in the local and regional trailway system
of south Washington County with the Cottage Grove Ravine Regional Park. Since the adoption of the original
AUAR, the Mississippi River Trail (USBR #45) was established and also provides a connection to the region,
state, and nation. http://www.mississippirivertrail.org/index.html . With the new residential developments within
the East Ravine, the City created several neighborhood parks developed that conform to the East Ravine Park
Master Plan.
In 2017, a major park infrastructure and amenity improvement project was completed in the Ravine Regional
Park by Washington County and the South Washington Watershed District.
26. A DVERSE VISUAL IMPACTS
The AUAR anticipates a development pattern similar to those uses in the surrounding area and does not anticipate any
adverse visual impacts as a result of the development scenario.
The statements in this section remain unchanged.
27. C OMPATIBILITY WITH P LANS
The City of Cottage Grove completed a previous comprehensive plan update in October of 2000. This plan update
identified the East Ravine area as a future development phase (or MUSA expansion area) that was dependent upon
completion of the South Washington County Interceptor. The plan established a strategy for detailed master planning of
the East Ravine as an implementation initiative. This project implements that initiative. The 2000 Comprehensive Plan
update included the necessary components to comply with the requirements set out in 4410.3610, subpart 1. A
comprehensive plan amendment will be completed as part of this project to update land use and infrastructure systems
according to the East Ravine Development Scenario.
In March of 2011, the City adopted the 2030 Comprehensive Plan which succeeded the 2000 plan that implemented
the East Ravine master planning process.
The 2040 Comprehensive Plan modified the land use in the quadrant located at 70th Street and Keats Avenue and in
the Cottage View Site. Commercial districts were changed to mixed use and the low, medium, and high density
districts were reconfigured.
The current Washington County land use plan has not been updated to reflect the land uses in the East Ravine
approved by the City and the Metropolitan Council. Future updates should be updated to current information.
The Washington County Comprehensive Plan guides the project area as long term agriculture with a density of 1 unit
per 40 acres. This plan is illustrated in Figure 27.2.
The Metropolitan Land Planning Act requires Comprehensive Plans to be updated by 2008. Future plan updates will
need to take into consideration the various land use patterns established in the development scenario master plan.
Plan was adopted by the City Council on March 2, 2011. This document reflects the
development scenarios identified in the AUAR. Future updates will reassess and reflect development scenarios that
have occurred or are to be modified in the East Ravine. The City has been working closely with the City of Woodbury
as land use and transportation changes related to development occur or are planned.
The adoption of the 2040 Comprehensive Plan kept the majority of neighborhood, transportation, and infrastructure
guidance established in the 2030 Plan and AUAR, with the exception of some land use classification changes from
Commercial to Mixed Use and the location reconfiguration of some Medium and High Density Residential
designated properties.
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28. I MPACT ON INFRASTRUCTURE AND PUBLIC SERVICES
WaterSee Appendix 1 Appendix 1A 2006 Water Supply and Distribution Plan
SewerSee Appendix 2 Appendix 2A Sanitary Sewer System, Cottage Grove 2040 Comprehensive Plan
Electricity
Electric utilities will be provided by local electric utility companies as guided by current codes and ordinances. Where
possible, electric utility lines will be buried under ground. Easements will be integrated into the system of open space
networks and road rights-of-way.
As development and road projects have been occurring since the adoption of the AUAR, the City has been
working with utility companies to place infrastructure underground. In some instances, this action is not cost
feasible. No change in statement.
Storm Water ManagementSee Appendix 5 5A 2019 Surface Water Management Plan
TransportationSee Appendix 3
TransitSee Appendix 3
Police and Fire Services
Police and fire service will be adequate to serve this area with the addition of employees in conjunction with added
population and commercial services.
The statements in this section remain unchanged. No change in statement.
School District
School districts will face added population as a result of this growth and will need to plan accordingly for added school
capacity. Areas within the development scenario do not specifically identify school sites but do provide opportunities to
incorporate elementary and secondary school facilities into future subdivisions.
The school district added the East Ridge High School and campus in Woodbury since the adoption of the AUAR.
This school serves portions of Cottage Grove including the East Ravine. Additional planning on school needs is
currently being completed by the school district. No change in statement.
Telephone and Cable
It is assumed that telephone and cable services would be extended to the area consistent with current services and
expansion policies. These would be underground services most likely placed in public right-of-way.
The statements in this section remain unchanged. No change in statement.
29. C UMULATIVE IMPACTS
No response required.
The statements in this section remain unchanged. No change in statement.
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30. O THER POTENTIAL ENVIRONMENTAL IMPACTS
There are no other environmental impacts to note.
The statements in this section remain unchanged. No change in statement.
31. S UMMARY OF I SSUES
See the Executive Summary.
The statements in this section remain unchanged. No change in statement.
M ITIGATION I NITIATIVES
I NTENT OF M ITIGATION P LAN
The development of the AUAR project area could have impacts on the environment and existing development. This plan
identifies existing tools and policies that the City of Cottage Grove has in place, as well as additional initiatives that will
need to be implemented to mitigate potential impacts. There are multiple ways in which Mitigation Initiatives may be
implemented such as:
Enforcing existing zoning and subdivision ordinances and other development regulations at the time of
development concept submittals, preliminary and final platting, and during construction monitoring activities
Referencing and implementing policy directions provided in the Comprehensive Plan and the East Ravine
Master Plan during the review and approvals of development projects
Planning and building public infrastructure (local roads, parks, trunk sewer and water systems) in conjunction
with private development initiatives
Maintaining and updating existing plans and studies for the community
Requiring additional field work/investigation as part of pre-development planning where potential
environmental or cultural resources may exist but have not been verified or where more detailed air quality
testing or noise monitoring may be needed.
The statements in this section remain unchanged. No change in statement.
G ENERAL M ITIGATION I NITIATIVES
This section identifies a series of mitigation initiatives that are general in nature and apply to all public and private
development within the AUAR.
1. All permits identified in the AUAR (see Question 8), as well as other necessary permits that may be
required will be secured by private parties, or the City as appropriate, for all development activities within
the project area.
2. The City will follow its own regulations, ordinances, plans, and policies currently in place in the review and
approval of all development activities within the project area. These items include the Comprehensive Plan,
the East Ravine Master Plan, and the official zoning and subdivision ordinances.
3. The City will extend public sewer and water services in a manner consistent with existing plans and
policies. The City will monitor capacities, update plans, and extend services as necessary to ensure
sufficient supply and quality of services.
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4. The City will implement a development tracking mechanism to monitor development within the AUAR
project area and its conformance with the development scenario using Geographic Information System
(GIS) Software and mapping.
5. The City will enforce its parkland dedication policies consistent with the goals and policies of the
Comprehensive Plan and Growth Area Plan, as well as the requirements of the subdivision ordinance.
The statements in this section remain unchanged. No change in statement.
F OCUSED M ITIGATION I NITIATIVES
Mitigation initiatives that are explicitly intended to mitigate or minimize impacts on a particular resource or action are
outlined by topic in this section.
Natural and Physical Resources
Historical and Cultural Resources: follow guidance in Comprehensive Plan and existing codes and ordinances.
The Documentation Supporting the Nomination of the Military Road Heritage Corridor to the City Register of Historic
Sites and Landmarks contains a greater account of the historical significance of the Military Road Heritage Corridor and
should be referenced for further details on the corridor. The report also contains a number of recommendations that lend
support to mitigation initiatives for the Cottage Grove East Ravine Pre-Design project. Those recommendations include:
The Military Road Heritage Corridor that are currently active roadways should be retained and preserved as an historic
route within the existing city-county roadway system. The segment that is no longer a roadway cutting diagonally across
Section 11 should be preserved as a rural historic landscape.
heritage education program. Possible interpretive resources include publications, wayside exhibits, bicycle tour cassette
tapes and guides, and school programs.
Maintain, whenever possible, the alignment, width, and grad of existing roadways that comprise the Military Road
Heritage Corridor. Roadway maintenance and reconstruction should comply with highway safety standards in such a
manner that the essential historic character of the Military Road corridor is preserved intact, respecting the existing
shape, slope, elevation, aspect and contour of the historic route.
Minimize disturbance of terrain in the abandoned segment of the corridor through Section 11 to reduce the possibility of
destroying unknown archeological features. When this area is developed, archeological surveys should be carried out in
accordance wi
The statements in this section remain unchanged. No change in statement.
Land Use Management
The city will continue to implement its Comprehensive Plan policies, as well as zoning and subdivision
regulations to ensure a development pattern consistent with the East Ravine Master Plan. New and existing
Comprehensive Plan and City Code regulations will be used to incorporate the design objectives of the Master
Plant. These include:
Existing Subdivision Ordinance requirements for preservation of natural features
New requirements for establishing landscaped buffer areas along major roadways.
New requirements for residential and commercial landscaping which provide sufficient green space which
minimizing irrigation requirements.
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New residential design standards which ensure a variety of housing design.
New requirements on screening requirements between commercial and residential areas. Particular emphasis
will be places on providing adequate screening between the existing residential areas and the future Cottage
View commercial area.
The statements in this section remain unchanged. No change in statement.
Erosion Control and Sedimentation
The city will enforce existing erosion control regulation for all new developments. These regulations are based
resources. These measures greatly reduce erosion and sedimentation during and after construction.
The statements in this section remain unchanged. No change in statement.
Water Supply and Appropriation
The East Ravine Master Plan includes a Public Water Supply Plan, which describes trunk watermain
improvements necessary to extend municipal water service to the area. The city will apply its Wellhead
Protection Plan to new and existing wells in the East Ravine area. This plan calls for abandonment and
sealing existing residential and agricultural irrigation wells to reduce the likelihood of future contamination of
groundwater supplies. Measures are also included in the plan for protecting future municipal well in the area
from contamination and to ensure regular testing of water supplied by these municipal wells.
The statements in this section remain unchanged.
The 2006 Water Supply and Distribution Plan incorporates the East Ravine area and describes the trunk
watermain improvements necessary to provide municipal water service. Since the adoption of the AUAR, Well #12
was drilled in Sunnyhill Park near Ideal Avenue.
Wastewater System
The East Ravine Master Plan includes a Sanitary Sewer Plan which describes trunk sanitary sewer
improvements necessary to serve the area. The city through its development review process will monitor and
verify estimated wastewater flows for conformance to the Sanitary Sewer Plan and treatment capacities of the
Metropolitan Council Environmental Services facilities.
The statements in this section remain unchanged.
The 2040 Comprehensive Plan includes a section on sanitary sewer which describes ultimate service areas, trunk
sewer lines, and connection points to the South Washington County Interceptor.
Storm Water Management
Development within the project area will increase the amount of storm water runoff. The City will ensure
require the development of a storm water management system which limits flooding and negative impacts on
water quality within the watershed. Key strategies will include:
Maintaining discharge rates at or below current levels Surface Water Management Plan or
by the South Washington Watershed District. No change in statement.
South Washington Watershed District No change in statement.
Pre-treatment of runoff prior to discharge into the Mississippi River to a downstream natural receiving water
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Adoption and enforcement of a Storm Water Ordinance
Cooperation with MPCA and other partners in development and implementation of strategies to meet the
Total Maximum Daily Load (TDML) standard yet to be determined
Design ponds
Manual Protecting Water Quality in Urban Areas Best Management Practices for Dealing with Storm
Water Runoff from Urban, Suburban and Developing Areas of Minnesota
Conformance to National Urban Runoff Pond (NURP) standards
Conformance to National Pollution Discharge Elimination System (NPDES) Phase II requirements as outlined
in the EPA Clean Water Act
Developments within the AUAR project area which impact wetlands will be subject to regulation under the
Wetland Conservation Act, Chapter 103G Waters of the State (i.e. Department of Natural Resources), and
possibly Section 404 of the Clean Water Act (i.e. Army Corps of Engineers). The City of Cottage Grove will
work with the Washington County Soil and Water Conservation District South Washington Watershed
District, the local government unit responsible for administering the MN Wetlands Conservation Act, on any
development impacting wetlands. Should wetland impacts be part of a development within the project area,
these regulatory programs have sequencing requirements which require applicants to demonstrate that
wetlands impacts have been avoided and minimized to the extent practical and, if impacts cannot be avoided,
these programs require replacement of wetlands impacted by fill or excavation.
The Ci
constructed and future/ultimate storm sewer facilities. New Atlas-14 rainfall depths were analyzed and incorporated
into the plan. The City will apply its Wellhead Protection Plan to new stormwater facilities in the East Ravine area,
limiting infiltration where applicable.
Traffic
Traffic will continue to grow as development occurs within the project area and as regional growth continues
to add traffic to the system. Appendix 3 contains a number of roadway and intersection improvements that
will serve to mitigate future congestion levels associated with growth in the region.
Results of noise analyses suggest that future traffic noise levels have potential t
allowable noise levels near major arterial and collector roadways in the project area. The City of Cottage
Grove is required to comply with Minnesota Rules 7030.0030. This statute requires municipalities to ensure
that existing noise levels comply with state noise limits prior to occupants moving into residences in the
proposed development. Barriers such as earthen berms or landscaping can reduce traffic noise levels.
Increasing the distance between the source and the receiver also reduces traffic noise levels (i.e. larger
setbacks from arterial or collector roadways). The Master Plan includes areas along major roadways that serve
as buffers that will offer separation between the noise source and the receivers.
The statements in this section remain unchanged.
Monitoring of Development and Future Updates to the AUAR
The AUAR assumes a hypothetical development scenario. Since it is based on assumptions it is important that
actual development be monitored and compared to the development that was assumed in the development of
final plat process the developer will submit electronic plats consistent with city development requirements in a
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of platted lots and the ability to tie building permits to the lots so that occupied housing units could be tracked
in the
As required by Minnesota Rule 4410.3610 Subpart 7, to remain valid, the AUAR must be updated if any of
the following events should occur:
Five years have passed since the AUAR and mitigation plan were adopted and all development within the
project area has not been given final approval.
A comprehensive plan amendment is proposed that would allow an increase in development than what was
assumed in the development scenario.
Total development within the area would exceed the maximum levels assumed in the environmental analysis
document.
Development within any subarea delineated in the AUAR would exceed the maximum levels assumed for that
subarea in the document.
A substantial change is proposed in public facilities intended to service development in the area that may
result in increased adverse impacts on the environment.
Development or construction of public facilities will occur differently than assumed in the development
scenario such that it will postpone or alter mitigation plans or increase the development magnitude.
New information demonstrates that important assumptions or background conditions used in the analysis
presented in the AUAR are substantially in error and that environmental impacts have consequently been
substantially underestimated.
The RGU determines that other substantial changes have occurred that may affect the potential for, or
magnitude of, adverse environmental impacts.
The AUAR is being updated because it has been over five years since the adoption of the document. None of the
other triggering events detailed above have been met.
The 2020 AUAR Update is being completed because the last update was approved on April 15, 2015.
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East Ravine AUAR 2020 Update
City of Cottage Grove
Figure 10.1
Natural Resources Inventory
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East Ravine AUAR 2020 Update
City of Cottage Grove
Figure 10.3A
Grassland/Shrubland Map
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East Ravine AUAR 2020 Update
City of Cottage Grove
Figure 10.3B
Lawn/Landscape Map
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East Ravine AUAR 2020 Update
City of Cottage Grove
Figure 18.1
Land Use with Ravine Boundary
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East Ravine AUAR 2020 Update
City of Cottage Grove
Figure 18.2
Sewer Districts and East Ravine Boundary
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East Ravine AUAR 2015 2020 Update
City of Cottage Grove
Figure 21.2
2014 2015 and 2040 Traffic Volume Map
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East Ravine 2020 Update
City of Cottage Grove
Figure 21.3
2040 Traffic with Ravine Parkway
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East Ravine AUAR -2015 Update
City of Cottage Grove
Figure 27.1
2030 Land Use Plan
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East Ravine 2020 Update
City of Cottage Grove
Figure 27.1A
2040 Land Use Plan
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East Ravine AUAR 2015 2020 Update
City of Cottage Grove
The Areas in Maroon are platted Properties, and the green is Park and open space
Figure 27.3
Upper Ravine District Development Update Detail
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East Ravine AUAR -2020 Update
City of Cottage Grove
Figure 27.4
2018 Roadway Functional Classification Map
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East Ravine AUAR -2020 Update
City of Cottage Grove
Figure 27.5
2040 Development Staging Plan
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