HomeMy WebLinkAbout2016-05-18 PACKET 07.H. Cottage
J Grove
��er� Pride and Qro�P�rity Me�t
Clt�/ COUI'1CII CONSENTAGENDA
Acfion Request Form �'H'
Meeting Date
5/18/2016
Department
Community Development
Title of Request
Dynamic Speed Display Sign Policy
Staff Recommendation
Approve the Dynamic Speed Display Sign Policy.
ATTACH MENTS:
Description Type Upload Date
Council Memo Cover Memo 5/11/2016
Dynamic Speed Display Sign Policy Backup Material 5/11/2016
Cottage
J Grove
�here Pride andp�OSPerity Meet
TO: Honorable Mayor and City Council
Charlene Stevens, City Administrator
FROM: Ryan Burfeind, Project Engineer
DATE: May 10, 2016
RE: Dynamic Speed Display Sign Policy
Background
As part of the 90th Street reconstruction in 2015, a joint meeting of the T--
Public Safety and Public Works Commissions was held on October 19„ SPEED �.
2015, to discuss safety and parking issues that were raised by residents. LIMIT
One of the issues identified was related to vehicle speeds on 90th Street. � O
An item that was presented to mitigate this issue was the installation of a
dynamic speed display sign to make motorists more aware of the speeds •,,, —
:.e■.d �
at which they were traveling. Various studies have been conducted on
the effectiveness of the installation of these signs. On average, a speed YOUR
reduction has been observed with the use of radar feedback; however„ S PE E D �1
the speed reduction has been found to be greater when paired with
enforcement. The estimated cost for installation of one dynamic speed
display sign with solar power is $6,000.
Based on the speeds that were observed, the Commissions recommended the installation of this
type of sign on 90th Street. The City Council approved this installation at their October 21, 2015,
meeting.
Discussion
In order to provide consistency for the installation of dynamic speed display signs in the City of
Cottage Grove, a policy has been drafted regarding installation and removal procedures. As part
of this process, the City reviewed installation policies for these signs from other agencies. While
policies varied from agency to agency, there was consistency that the signs would be used on
higher volume roadways with a measured speeding issue. Based on this information, the policy
on dynamic speed display signs proposes to limit installation to roadways classified as a major
collector or higher where the 85th percentile speed is 5 mph greater than the posted speed limit.
Special consideration would also be given for the installation of signs in speed sensitive areas
such as school zones. When the installation criteria are met, it will be brought to the Public
Services Commission for review and the City Council for approval.
For installations related to an identified speeding issue, the City will have the option to revisit the
situation to determine if the sign has had a measurable effect on vehicle speeds. If the 85th per-
centile is measured to be less than 5 mph over the posted speed limit, the City will have the
option to relocate the dynamic speed display sign to another approved location. The relocation of
Honorable Mayor, City Council and Charlene Stevens
Dynamic Speed Display Sign Policy
May 10, 2016
Page 2 of 2
a dynamic speed display sign would be brought before the Public Services Commission for
review and City Council for approval.
The Public Services Commission reviewed the Dynamic Speed Display Sign Policy at their April
20 meeting. The Commission recommended the City Council approve the Dynamic Speed
Display Sign policy with a vote of 10-0.
Recommendation
It is recommended the City Council approve the Dynamic Speed Display Sign Policy.
Cottage
J Grove
�here Pride and Pr�sperity Meet
DYNAMIC SPEED DISPLAY SIGN POLICY
CITY OF COTTAGE GROVE
The City of Cottage Grove installs Dynamic Speed Display signs, which are warning
signs, to provide drivers with speed feedback in speed transition zones where observed
driving speeds may exceed the posted speed limit or in speed-sensitive areas. Dynamic
speed display signs will be considered when the following criteria are met:
1. 85th percentile speed is more than 5 mph over the posted speed limit.
2. Street must be classified as a major collector or greater.
Special consideration will be given for the installation of signs in speed sensitive zones
such as school zones.
Rationale:
When recognized and complied with, Dynamic Speed Display signs can be an effective
tool in reducing average running speeds to a value closer to the posted speed limit or
advisory speed limit. Various research studies indicate that the effect on speed
reduction varies depending on the location where the sign is installed and may vary in
time after the initial sign placement.
Dynamic Speed Display signs typically supplement regulatory speed limit signs or
speed warning signs and are mounted either below or beside the main sign. In addition,
they are not enforceable, only informational, and show speeds in yellow dynamic
lettering on a black digital background.
Procedure:
If a situation is identified that meets the minimum criteria for installation of a dynamic
speed display sign, it will be brought before the Public Services Commission for review
and the City Council for final approval. Upon City Council approval, appropriate signs
are then installed and maintained by the City.
For installations related to an identified speeding issue, the City will have the option to
revisit the situation to determine if the sign has had a measurable effect on vehicle
speeds. If the 85th percentile is measured to be less than 5 mph over the posted speed
limit, the City will have the option to relocate the dynamic speed display sign to another
location. The relocation of a dynamic speed display sign would be brought before the
Public Services Commission for review and City Council for approval.
Dated: May 2016
CITY OF COTTAGE GROVE• 12800 Ravine Parkway•Cottage Grove, Minnesota 55016
www.cottage-grove.org•651-458-2800• Fax 651-458-2897• Equal Opportunity Employer