HomeMy WebLinkAboutWillson/College Intersection Improvements1
Commission Memorandum
REPORT TO: Honorable Mayor and City Commission
FROM: Debbie Arkell, Director of Public Services
Richard Hixson, City Engineer
Chuck Winn, Assistant City Manager
SUBJECT: Willson/College Intersection Improvements
MEETING DATE: October 4, 2010
AGENDA ITEM TYPE: Action
RECOMMENDATION: It has been determined that either a traffic signal or a roundabout can
be installed at the intersection of Willson Avenue and College Street to reduce the number of
accidents at the intersection. Both require a minor amount of additional right-of-way. The
following table lists some pros and cons for each option (likely more than listed):
PROS CONS
SIGNAL Should reduce angle crashes Long queues can impact driveways
Drivers are familiar with signals Adds delay to drivers
Requires less r/w (379 sq.ft.) Can increase rear-end collisions
Lower cost than roundabout Bozeman HPAB opposed to signal
Can assist with pedestrian crossings Loss of parking along west side of
Willson with 23 spaces remaining,
include 3 new spaces for daycare
Higher speeds through intersection
Increase air quality emissions
More noise created from vehicles
starting and stopping at intersection
ROUNDABOUT Traffic flows continuously Requires additional r/w (773 sq.ft.)
Lower speeds makes easier for drivers
to safely enter intersection and results
in less severe crashes
Loss of parking near intersection.
25 spaces available includes 3 new
for daycare
Minimal queues and traffic backup Possible impact to trees near
intersection
Fewer conflict points than with a
signal
Additional lighting needed (can use
“period lighting” to match existing)
Shorter pedestrian crossing distances -
one lane at a time
More difficult for blind pedestrians
to cross roundabouts than signals
Less air quality concerns Higher cost than signal
Quieter for neighborhood because less
starting and stopping
82
2
From a traffic safety standpoint, either option will mitigate the current accident rate, with studies
showing there are fewer and less severe crashes at a roundabout compared to a signal. As
explained in detail on pages 6 and 7 of this report, the Bozeman Historic Advisory Board
recommended an island be installed on Willson Avenue to prohibit cross traffic or left turns from
College Street and if this was not feasible, they supported a roundabout. They were
“emphatically opposed” to a signal at this intersection or any other intersection within the
Historic District of South Willson Avenue. MDT and the Historic Preservation Staff are also
aware that one or two property owners have indicated they are not desirous to provide the right-
of-way necessary for improvements, so that may be an issue of contention for either option. The
City Commission should review the information and public comment, and determine
whether a signal or a roundabout is the best option for improvement to this intersection,
and ask the Montana Department of Transportation to proceed with installing that option
at the intersection of Willson Avenue and College Street with funding from the Traffic
Hazard Elimination Program.
BACKGROUND: There is a considerable amount of history on this project which this memo
attempts to summarize. Additional information and detail is available in the City Engineer and
Public Services Director offices. Full meeting packet materials and minutes from previous City
Commission meetings can be obtained from the City Clerk’s office.
Each year, the Montana Department of Transportation requests cities to submit high-accident
intersections that might be eligible for the Traffic Hazard Elimination Program. City staff
reviews the intersection accident history reports and the Transportation Plan Update, and makes
recommendations to the Department on which intersections that have a rate of high accidents that
they recommend be improved. If an intersection is selected, the Department then completes a
review to determine if the intersection(s) qualifies for the funding.
In 2002, City Staff recommended the Willson/College intersection be improved through this
program. Willson Avenue is designated as a minor arterial and at that time carried
approximately 12,000 ADT south of the intersection and 11,800 ADT north of the intersection.
(2005 ADT volumes as shown in the 2007 Transportation Plan Update show 11,300 ADT north
and 9,200 ADT south). College Street is designated as a collector street and in 2002 carried
approximately 1,400 ADT east of the intersection and 440 ADT west of the intersection. The
2005 ADT volumes east of the intersection are 3,800, an increase of over 2.5 times the 2002
volumes.
Accident history from January 1, 1999 through December 31, 2001 (pre-design) included 16
accidents in a three-year period, 6 of which were injury accidents resulting in 15 injuries. From
January 2005 to November 1, 2005, there were five accidents reported at this intersection. From
January 1, 2007 to December 31, 2009, there were 10 crashes at the intersection.
Both Willson Avenue and College Street are designated Federal Aid Urban routes, meaning they
are eligible for federal funding for improvements, and that MDT must approve all improvements.
In 2003, MDT review determined that 4 of the 8 warrants were met and they found that a traffic
signal was warranted.
83
3
On December 2, 2004, the Montana Department of Transportation held a public meeting at the
GranTree Inn regarding the proposal to install a traffic signal at the intersection of Willson and
College. Danielle Bolan, MDT State Traffic Engineer, presented the project, explained the
process used to determine if a signal is warranted, and noted they looked at the following ways to
make the intersection safer: signal; 4-way stop, which shifts the delay over to Willson, but
provides good level of service on College; and use of left turn lanes to keep through-traffic
flowing on Willson. The Department reviewed the information received, both at the meeting and
in writing after the meeting, and extended the public comment period
The Department reviewed several different options, and presented those options at a City
Commission work session on May 9, 2005. Issues raised at that meeting were the
aesthetics/appearance of the light; should left turns from Willson onto College be eliminated;
does all parking have to be eliminated; what other options are available, such as a flashing light.
The options reviewed include a 4-way stop; the current 2-way stop; a traffic signal with turn
lanes; and a traffic signal without turn lanes. Based on that evaluation, the Department
determined a traffic signal with left turn lanes was the best alternative. Public comment was
taken at this meeting, with concerns expressed regarding the impact to the historic character of
the neighborhood, the amount of parking that would be removed; impact on driveways; traffic
backup and air emissions.
The revised design was presented at a special neighborhood meeting held at the Longfellow
School Gymnasium on November 9, 2005, with over 60 people in attendance. The purpose of
the meeting was to provide residents with information regarding the professional
recommendations being made by MDT for the proposed stoplight, outline the revisions made
following the May 9th City Commission meeting, and provide the public with an opportunity to
ask MDT and City staff questions regarding the project. Based on comments heard at the May 9,
2005 meeting, MDT revised its initial design to retain as much on-street parking as practicable,
and by reducing lane widths and shortening tapers they saved about 20 spaces. The design
proposed keeping the left turn lane for southbound traffic because left turn movements would
likely generate queues of vehicles that may shift vehicles wishing to make left turns to other
intersection (i.e., through adjacent neighborhoods), and only one more parking space could be
saved by dropping that turn lane. Black powder coated signal poles were also proposed. One of
the most vocal issues expressed during the meeting was that the Historic Preservation review
portion of the Environmental Assessment Document (NEPA, Categorical Exclusion, Cat X) was
not yet completed, and a decision should not be made by the City Commission to proceed with
the signal until that was completed.
A fourth public meeting was held by the City Commission on November 14, 2005, and was
facilitated by Jim Madden from the Community Mediation Center.
The South Willson Improvement Association submitted a written counterproposal that included
the following:
· The improvement of sight distance from College Street onto Willson Avenue through the
elimination of parking for only a distance of 100 feet from the intersection in all
directions, but allowing for the “drop off” area on the southeast corner for the Children’s
Development Center.
· Enhance this intersection with landscaping, marking it as special and more visible.
84
4
· Special signage, denoting Historic District, at key entrance streets such as Willson.
· The elimination of the proposed turning lanes. Maintain the current lane width for
through traffic flow, safety, and parking beyond 100 feet for north and south on Willson.
· The installation of “minimum cost” measures including larger stop signs and stop ahead
signs along College Street, boldly alerting drivers of the upcoming intersection.
· The installation of a photo-ticketing device at the intersection and the strict enforcement
of the 25 mph speed limit.
At this meeting, the MDT District Administrator asked the Commission to commit to whether
they support the installation of a signal at this intersection, because if a signal was not supported
by the commission, the Department would not continue their review and would dedicate their
resources elsewhere. They stated if the Commission continues to support the possibility of a
signal, they will continue the review, and added that the signal cannot be installed without
resolving any adverse effects identified during the Section 106 Historic Preservation review.
Comments were received both supporting and opposing a traffic signal, and several questions
and new ideas were proposed that were further investigated by MDT. These included: Can the
signal be designed with no left-turn lane for southbound Willson traffic to turn east onto College;
enhance the intersection to make it more special and visible; add special signage for the historic
district; eliminate the proposed turn lanes so current lane widths can be maintained; install
“minimum cost” measures like larger stop signs and stop ahead signs along College Street to
alert drivers of the intersection; and install a photo-ticketing device at the intersection and strictly
enforce the posted speed limit.
A summary of the November 9 neighborhood meeting was presented to the Commission on
November 14, 2005. The Commission asked MDT to further research the feasibility of a signal
with no left southbound turn onto College; a roundabout; the neighborhood association’s
proposals; no signal with a left turn lane on Willson for north-bound traffic; and to further
address driveway access issues, and to report back to them on December 5, 2005.
At a public meeting on December 5, 2005, The Montana Department of Transportation Traffic
Engineers provided the Commission their response to issues identified at the November 14, 2005
public meeting. In addition to the original proposal to install a signal with left turn pockets for
both northbound and southbound Willson Avenue traffic, two new scenarios were presented to
the Commission which will also mitigate the existing crash pattern. Those options were:
1. Install a signal with no left-turn lane for southbound Willson Avenue traffic to turn
east onto College Street. This would allow the parking situation to be as it exists
today, with the exception of the residence on the northwest corner, and no parking
would be allowed on Willson Avenue in front of that residence.
2. Install a roundabout at the intersection, which could fit if additional right-of-way is
obtained at each corner. Parking would be eliminated for approximately 80-100 feet
on each corner of the intersection. The designated drop off area for the Children’s
Development Center may have to be moved a little further east or reduced to allow
for the proper operation of the roundabout. Curb and sidewalk would have to be
removed and replaced, which would include reconstruction of ADA ramps. Any
costs over the benefit/cost would be the city’s responsibility.
85
5
Public comment expressed support of the roundabout, the importance of preserving the character
of the historic neighborhood, concern of noise and light pollution from a signal; concern the
neighborhood’s plan would not allow west turns from the intersection; support of a traffic signal
for safety; concern about the removal of parking. In addition, several letters both in support and
opposing a signal were submitted. These letters are available in the Clerk’s, Public Service
Director’s, and City Engineer’s office, and likely on-line with each meeting packet.
At the meeting, MDT asked the Commission to take official action, noting that they have
compromised as far as they can and still provide a safe intersection for the traveling public. MDT
officials advised that by giving them the direction to proceed, the funds would be committed, but
if the City elected to not install any improvements, the City would be responsible to reimburse
them for the design costs.
On December 5, 2005, the City Commission voted 4-1 to direct MDT to forward both a
revised traffic signal design and roundabout design to the next step in the process, with
preference given to the roundabout first, and a traffic signal with no eastbound left turn
lane as the alternative option.
On November 27, 2006, the Department returned to the City Commission. The completed
Design Option Comparison presented found that a roundabout would have an adverse impact on
the Bon Ton Historic District, and recommended that a traffic signal be installed to address crash
trends and improve traffic operations at the intersection. At this point, five public meetings had
already been held on this project, and there were three City Commissioners who were not on the
Commission when these meetings were held and direction given.
A Comparison of Intersection Design Options for the intersection was prepared for the
Department by Robert Peccia & Associates and presented to the Commission at the November
27, 2006 meeting. The comparison included a thorough analysis of both the signalized
intersection as well as the roundabout option, and provided a detailed comparison of the signal
and roundabout for:
· Operational effects (LOS, queues, travel speeds, design life, would it cause traffic to shift
to side streets, access to public transportation, affect on vehicular access, construction
and operating/maintenance costs, special maintenance);
· Effects to on-street parking and driveways (how much parking would be lost; impact on
residential driveways);
· Effects to sidewalks and pedestrian crossings;
· Effects on traffic safety (how each would address accident trend of broadside crashes,
potential for a change in the type of crashes);
· Effects on pedestrian and bike safety;
· Environmental effects (need of right-of-way, relocation of housing or businesses, impact
on utilities, is project consistent with land use plans and zoning, would design induce
changes in land use and density or induce growth, impact on residents with special needs,
emergency service facilities, response times, traffic noise, air quality impacts, visual
impacts/aesthetics);
· Social impacts/environmental justice;
· Economic impacts;
· Other environmental resources.
· Effects to Cultural Resources
86
6
With regard to effects to Bon Ton Historic District, MDT had received a letter from the State
Historic Preservation Officer concurring with the Study’s determinations that the signalized
intersection option would have No Adverse Effect on the District, and that the roundabout design
would have an Adverse Effect to the District. The factors supporting the determination of a
roundabout (RAB) having an Adverse Effect on the District included:
· RAB would be an entirely new form of intersection treatment in the Bon Ton Historic
District. There is no precedent for the use of a RAB in an historic district in Bozeman;
· Because of the design features, the RAB would be significantly different from the
existing streetscape by placing a round feature within an historic grid pattern street
system;
· The RAB would require substantial amounts of new r/w at each of the four quadrants of
the intersection. The circular configuration of the RAB would result in the reconstruction
of sidewalks and boulevards at the intersection to make them conform to the new layout.
This would also be a deviation from the traditional grid pattern of the historic district and
result in wider boulevards and sidewalks located closer to historic properties built to
conform to the RAB;
· Approximately 9 to 12 mature trees located in the boulevards but associated with the
historic properties would have to be removed. The mature trees in the boulevards have
historically provided a screen between the historic properties and the street and, more
importantly, helped define the historic character of the historic district. Their loss would
significantly change the appearance of the neighborhood.
· Two historic lampposts would have to be relocated, which would upset the staggered
configuration and spacing between other lampposts on Willson Avenue in the historic
district;
· Additional street lighting would have to be added to the intersection to make the RAB
safer. The RAB would also require significantly more regulatory and guidance signage
on each approach.
· Considered together, these impacts and the addition of modern street features would
significantly diminish the historic character and appearance of the neighborhood.
In summary, the report found the project is a safety improvement designed to address crash
trends and improve traffic operations at the intersection. Based on the results of the study
finding that the roundabout would have an Adverse Effect to the historic district, while a signal
has No Adverse Effect, MDT planned to move forward with the design of a signalized
intersection at this location. The Commission was advised that if a signalized intersection
treatment is no longer the City’s preferred option, the City will be required to reimburse MDT’s
costs to date, which are estimated at $82,000.
At the November 27, 2006 meeting, a motion passed 4-1 to direct staff to work with MDT to
facilitate the alternate of a roundabout and historic mitigation and authorize the use of up
to $3,000 to acquire a second opinion on the adverse impact of the roundabout within an
historic district.
With regard to impact on the historic district, MDT staff continued to meet with the State
Historic Preservation Office and local Historic Preservation Advisory Board. In November 2009
the State Historic Preservation Office concurred with the MDT’s Historian that both options –
traffic signal and roundabout - would have No Adverse Effect on the historic district. MDT staff
87
7
also met with the local Historic Preservation Advisory Board, and on October 12, 2009, the
Board presented MDT with the following comments and recommendations:
1. First, we recommend that MDT consider options for this intersection which are less
intrusive than those currently proposed. One option would be to construct a landscaped
median through the intersection on Willson, thus ending through traffic on College and
all left turns at the intersection. This would have less impact on the historic streetscape,
and have the added benefit of not encouraging through traffic on College, a narrow street
also running through the historic district.
2. If an option similar to the one described above is found not to be feasible, the Board
support the construction of a roundabout at the intersection, provided the guidelines
specified in your September 1 letter to minimize visual impact are followed. We
encourage MDT to further explore alternative designs for the roundabout, ones that could
slightly shift the roundabout to the southwest, lessening the impact on the historic
resources that are closest to the street.
3. We emphatically oppose the installation of a traffic signal at this intersection, or at any
other unsignaled (sic) intersection on South Willson Avenue.
UNRESOLVED ISSUES: Whether to improve the intersection with a signal or a roundabout.
ALTERNATIVES: The Department has proposed two options:
1. Install a signal
2. Install a roundabout
3. As suggested by the Commission
FISCAL EFFECTS: The Butte District MDT Administrator has confirmed that the entire cost
of either a signal or roundabout, including the purchase of necessary right-of-way, would be
entirely funded through the Traffic Safety Hazard Elimination program.
Attachments: MDT PowerPoint program
Report compiled on: September 23, 2010
Cc: Jeff Ebert, P.E., MDT
LeRoy Wosoba, P.E., MDT
88
STPHS 1209(2)
89
Intersection of South Willson Ave and College St, currently stop control on College St
Project nominated and programmed in 2003 as a safety project to signalize the intersection to address identified crash trend
During the public involvement process MDT was asked to look at a Roundabout
This intersection is discussed in Greater Bozeman Area Transportation Plan (2007 Update)
Is the City’s preferred option signal or roundabout?90
From Pre-Design Report
•16 Crashes in 3 year period –1 Jan ‘99 to 31 Dec ‘01
•10 Right angle
•3 Left-Turn opposite direction
•2 Rear end
•1 Pedestrian
91
Crashes from 1 Jan ‘07 to 31 Dec ‘09
•10 Crashes in 3 years
•4 Right angle
•4 Rear end (All on S Willson Ave)
•2 Single vehicle
92
Traffic Signal
Roundabout
93
94
95
Signals assign right-of –way to various
conflicting traffic movements can reduce
angle crashes
Drivers are familiar with traffic signals
Less additional right-of-way than
roundabout 379 ft²
Lower cost than roundabout
Can assist pedestrian crossings
96
Potential for long queues with signal this can impact private accesses
Adds delay as drivers are required to stop
Can increase rear end collisions
Considered to be an Adverse Effect to the Historic District by the Bozeman Historic Preservation Advisory Board
Loss of parking along west side of WillsonAve, 23 remaining spaces, includes 3 new for daycare
Higher speeds through intersection
97
Traffic can continuously flow through a
roundabout –only yield not stop
Lower speeds in a roundabout
•Easier for drivers to choose an acceptable gap
•Results in less severe Crashes
Minimal queues with roundabout
Fewer conflict points in a roundabout
Shorter pedestrian crossing distances,
one lane at a time
98
Roundabout requires additional right-of-
way 773 ft²
Possible impacts to trees at intersection
Loss of parking near the intersection 25
spaces available, includes 3 new for
daycare by widening into boulevard
Additional lighting needed for the
splitter islands of the roundabout (can
use period lighting to match existing)
99
What is the City’s Preferred
Design Option?
100