Van Buren Traffic Petition
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CITY OF DUBUQUE, IOWA
MEMORANDUM
November 10, 1999
TO: The Honorable Mayor and City Council Members
FROM: Michael C. Van Milligen, City Manager
SUBJECT: Van Buren Traffic Petition
In April, with the plans for reconstruction of Van Buren Street, the City Council
received a petition for the installation of a four-way stop at the intersection of Alpha
Street and Van Buren Street. The City Council did not approve the stop sign, but
directed City staff to further investigate the situation and other possible traffic calming
options.
The City's investigation determined that the accident rate is 0.84 accidents per million
vehicles entering the intersection. This is a low rate of accidents and is indicative that
there is not a problem with the current two-way stop condition at the intersection.
Traffic volumes were surprisingly low, ranging from 24 hour totals of 590 to 674
vehicles per day. These volumes are typical of low volume residential streets.
The results of the travel speed analysis and the unexpectedly low traffic count
indicates that van Buren is not the high speed diverter of traffic between University
and Pennsylvania Avenue as originally thought.
Public Works Director Mike Koch is recommending that the street be reconstructed as
it currently exists, without any realignment or stop signs.
I concur with the recommendation and respectfully request Mayor and City Council
approval.
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I\Mchael C. Van Milligen
MCVM/j
Attachment
cc: Barry Lindahl, Corporation Counsel
Tim Moerman, Assistant City Manager
Mike Koch, Public Works Director
CITY OF DUBUQUE, IOWA
MEMORANDUM
November 8, 1999
TO: Michael C. Van Milligen, City Manager
Michael A. Koch, Public Works Director 1I./;f/c{;
FROM:
SUBJECT: Van Buren Traffic Petition
INTRODUCTION
On April 1, 1999, a petition was received from David Reardon and 28 other
homeowners for the installation of a four-way stop at the Intersection of Alpha Street
and Van Buren Street.
DISCUSSION
The City's investigation determined that the accident rate is 0.84 accidents per million
vehicles entering the intersection. This is a low rate of accidents and is indicative that
there is not a problem with the current two-way stop condition at the intersection.
Traffic counts also indicated that the intersection does not meet the warrants for multi-
way stop signs.
This is the only four-way intersection along Van Buren, as you can see on the attached
map. The offset between the two portions of Alpha Street north and south of Van
Buren is a problem and would place the stop signs approximately 100 feet apart. The
legs of the intersection are completely separated, creating a question whether this is
really one intersection, or two; and whether the stop signs would require one stop or
two. All of the other intersections along Van Buren Street are "T"-intersections, none
of which would be conducive to stopping traffic on Van Buren Street. Consequently,
the City Council denied the petition on October 4, 1999.
The City Council did, however, suggest that alternatives be considered for slowing the
traffic down within this corridor. Travel speeds taken along the corridor range from
85th percentile speeds of 29.8 miles per hour to 34.5 miles per hour. These speeds
are certainly within the range of expectancy of the current 25 mile-per-hour speed
limit. Traffic volumes were surprisingly low, ranging from 24-hour totals of 590 to
674 vehicles per day. These volumes are typical of low-volume residential streets.
Besides the installation of a four-way stop, other "traffic-calming" techniques could
include narrowed pavement at intersections, diagonal diverters, mid-block bulbouts,
traffic circles, partial intersection closures, total street closures, and many others.
Enclosed are several options considered by City staff both before and after the public
hearing on the project. Most of these options center around some form of diversion
of traffic near the intersection of Van Buren and Drexel, which is about at the middle
of the street.
RECOMMENDATION
The results of the travel speed analysis and the unexpectedly low traffic count
indicates that Van Buren is not the high-speed diverter of traffic between University
Avenue and Pennsylvania as originally thought. These speeds and traffic volumes are
among the lowest we have ever analyzed and below the threshold where corrective
traffic control devices have ever been utilized. In my opinion, the street should be
reconstructed as it currently exists, without any realignment or stop signs. Experience
in other reconstruction projects has shown that there is not an increase in travel
speeds as might be anticipated subsequent to a paving project with its smoother riding
conditions. Before and after traffic studies have shown this to be the case time after
time.
While I don't believe that any corrective action is necessary, if the Council chooses to
proceed, I would recommend a design which would not require a lot of roundabout
traffic diversions. Such an alternative would be to narrow the pavement in the vicinity
of the Alpha Street intersection, since this is where the highest traffic speed was
recorded, as traffic comes off Pennsylvania eastbound on Van Buren.
I believe the narrowed pavement concept is the best alternative since it does not
change existing traffic patterns or possibly create other problems associated with
many of the other alternatives studied. Attached is a sketch of such a concept which
can still be incorporated into the project even though the project is already under
construction.
ACTION TO BE TAKEN
The City Council is requested to consider the traffic analysis and recommendation and
to give direction to City staff on the various alternative concepts studied, or new
concepts not yet addressed. If there is consensus to proceed with some form of
traffic control, City staff would then set up meetings with the neighborhood to address
alternatives.
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