The Northfield City Council is poised to approve a design for a roundabout plus bike and walk facilities at Jefferson Parkway and Division Street/TH246.
This is a once-in-a-generation large project to begin to reconnect Northfield could have been avoided or been approached incrementally if the City and School District had made more future-thinking, system-level decisions. Perhaps revisiting the history could/should help the City avoid having to spend taxpayers money to fix problems it largely created for itself.
More generally, how should the Council make its decision? Project cost is often the only objectively comparable metric among alternatives, but City staff could make clearer recommendations about why one alternative is preferable based on Northfield policy and data-supported best practices rather than presenting information as if all options are equivalent. Public input is important for preference, but polling and “dot-mocracy” should not determine the outcome of a complex project.
So, let me put a large number of words in the mouths of City staff to imagine what I wish they had said as they write their staff report for the City Council:
City Council Meeting Date: September 3, 2019
To: Mayor and City Council
From: City staff
Subject: Consider Motion authorizing Jefferson Parkway & Trunk Highway (TH) 246 Roundabout Final Design.
Action Requested: Staff Recommends a motion authorizing Jefferson Parkway & TH 246 Roundabout Final Design with Roundabout Design Alternative 2 that will include a pedestrian crossing with bumpout Option 2 design for the high school crossing.
Summary Report:
246/Jefferson Parkway Intersection Control Evaluation
The City initiated the Intersection Control Evaluation study at the intersection of Trunk Highway (TH) 246 and Jefferson Parkway in 2016. The goal and objectives of the intersection study were as follows:
- Identify improvements that alleviate peak hour congestion,
- improve pedestrian and bike access,
- improve school ingress/egress,
- improve safety and
- understand adjacent intersection operation impacts.
Over approximately the last 30-40 years, City land use and transportation decisions have created the problems we are now trying to solve. No single decision caused the significant vehicle congestion during school arrival and dismissal times or the dangerous conditions for people driving, walking, and riding. However, the sum of the approval of residential subdivisions which did not have continuous and connected streets, annexation of land and approval of school site plans without sufficient consideration of how people, especially kids, would reach them has resulted in the problem we now have the opportunity to begin to solve.
Presenting this historical survey before turning to the Intersection Control Evaluation is intended to assist the Council in decision making for this project and in the future by highlighting the consequences of disconnected decision-making.
History of decisions
South of Woodley Street, the grid street pattern of the older Northfield neighborhoods was abandoned with longer blocks, fewer connecting streets, and many cul de sacs or dead end streets.
The residential subdivisions on either side of TH246, both north and south of Jefferson Parkway were approved without requiring streets to connect outside the subdivision except to major collector streets. Homeowners appreciated the low traffic streets, but the long-term consequences are few opportunities to improve connectivity.
The 2008 Comprehensive Transportation Plan called out this “lack of interconnected neighborhoods” resulting in an “overreliance” on TH246 and Jefferson Parkway.
The residential subdivision to the west of TH246 was designed with multiple culs de sacs radiating off a single loop (Roosevelt Drive) with no opportunities to connect to surrounding destinations. The only exit is from Roosevelt Drive onto Jefferson Parkway. And, more recent research shows that the cul de sac – collector pattern is less safe than a more grid-like pattern which slows and distributes traffic. Crash data in the 2008 Comprehensive Transportation Plan seems to support this conclusion:
The Northfield Public School District’s choices (permitted by the City) are also significant. Locating Bridgewater Elementary School and Northfield Middle School directly south of the Northfield High School resulted in the highly concentrated congestion coming from school-related vehicle trips. Bridgewater is a neighborhood school, but all public school students must travel to the very southmost location of the only high school and middle school in the City. Significant bus traffic as well as students driving and middle school parents chauffeuring their children must pass through the TH246 and Jefferson Parkway intersection every day and within a compressed time period because the City prevented alternative routes through its subdivision decision-making.
The October 2001 Traffic Impact Report for the middle school anticipated increased traffic on Jefferson Parkway from the school and continued residential development. Analyzing this corridor, consultant Yaggy Colby Associates recommended installing the median which now exists saying “will provide more direction for drivers, which will in turn make it a safer corridor” and provide “refuge for pedestrians” crossing the wide street. This choice has proved to make Jefferson more difficult for school buses and large vehicles to access schools as well as significantly more dangerous for people on bikes.
In summary, this project highlights how short-sighted decisions over time have made mobility and access more difficult in this part of the City. Northfield should work to change its development approval process to require street connectivity with particular emphasis on helping people walking and biking and people with disabilities move along and across streets. Major community facilities such as schools should be planned with the developer as to siting and access for all to prevent the need for retrofitting in the future.
Northfield Planning documents
At least since Northfield Middle School opened in 2004, Northfield’s planning documents and adopted policies have clearly supported the position that Northfield will be a place where people can walk, roll, and ride bikes safely and easily, streets will connect, and where the natural environment is protected as we work to mitigate climate change. These plans include:
- Comprehensive Plan (2008),
- Safe Routes to School Plan (2009),
- Complete Streets policy (2012),
- Parks, Open Space and Trails Plan (2008 with an update in 2019) and
- Climate Action Plan (in draft form).
These policy documents guide staff’s recommendation for the design for the TH246 and Jefferson Parkway intersection and are supplemented by other City bike and walk events such as the 2014 Bikeable Community Workshop as well as current best practices in bike and pedestrian design.
Current Project
As stated above, staff identified these goals for this project
- Identify improvements that alleviate peak hour congestion,
- improve pedestrian and bike access,
- improve school ingress/egress,
- improve safety and
- understand adjacent intersection operation impacts.
Congestion and vehicle safety
All alternatives in the Feasibility Study recommend constructing a single lane roundabout. This design is recommended for improving vehicle congestion more than other intersection controls such as stop signs or signalized intersections.
Roundabouts smooth out traffic flow by eliminating the need to stop. A single-lane roundabout is also safer for cars based on data showing a 78% reduction in severe crashes and 48% reduction in overall crashes. Roundabouts slow traffic which reduces crash severity and the reduction in conflict points make vehicle crashes less likely.
Staff recommends Council consider collaborating with the Northfield School District after this project is completed to update the Safe Routes to School Plan and encourage schools to adopt Safe Routes to Schools programs to increase walking and biking to further reduce school-generated congestion as well as support City goals for transportation and climate action.
Bicycle and pedestrian safety
All alternatives studied include the single lane roundabout, but the other goals for this project are not addressed equally by all alternatives. Staff strongly recommends selecting Alternative 2 for the following reasons; another choice should require findings of fact to justify a less safe alternative for people walking and biking.
The peak hour traffic volume and the “no stop” characteristic of roundabouts make the roundabout design challenging to navigate for people walking and riding, especially school children likely to be using the intersection during peak times. Further, roundabouts have been shown to be especially difficult for people with low vision or blindness.
Staff emphasize that for people walking and riding, safety requires more than statistical safety or “no dead people” but includes whether people feel safe as they move through this intersection. The Complete Streets statement to make streets safe for people of “all ages and abilities” requires subjective as well as objective safety to ensure people walking and biking must feel protected from traffic by a barrier or sufficient distance, be able to navigate turns and crossings easily, on a route is free from debris and hazards as well as harassment or crime.
Staff opinion is that only grade separated bicycle and pedestrian facilities will meet this standard. The Feasibility Study identified underpasses rather than overpasses as more cost effective; Alternatives 2 & 3 both provide grade separated facilities.
Alternative 3 is not recommended. This alternative does provide grade separated facilities, however, the significant space below grade presents maintenance issues, longer trips when traveling in a single one direction, and social safety issues of blind corners and the need for additional lighting and/or supervision. The Mill Towns State Trail heightens the need to avoid diverting all routes to the center which could require additional wayfinding aids to mark the route for the anticipated increase in bicycle traffic through this intersection.
Public input from Polco and public meetings reinforce the perception of safety of Alternative 2, but public input should never be relied upon in the absence of supporting data, congruence with policy, and professional judgement.
Staff recommendation for TH246 and Jefferson Parkway
Staff recommends Alternative 2. This option is preferred to Alternative 3 as it is the best option for meeting the standard of a safe route for people of all ages and abilities and furthers Northfield’s policy goals through grade separated facilities and short, direct passage beneath the roadway which will increase perceived safety; this is the only alternative recommended to safely and conveniently reconnect this section of Northfield.
Staff recommendation for the Northfield High School crossing
Staff recommends Option 2 for the High School crossing. Both Options 1 and 2 preserve bicycle access through the curb extensions, but Option 2 provides (1) a shorter crossing distance shown to be safer by allowing more rapid crossing and less vehicle delay, and (2) physical protection for people waiting to cross and riders bicycling through the crossing.
Future needs
This project will be a major step toward reconnecting major community destinations, enabling safe walking and bicycling to school, and improving safety for all users of the intersection. However, additional steps will be needed in the future to complete the network including:
- change the High School entrance to a right in-right out design to prevent difficulties turning left onto Division Street in heavy traffic in close proximity to this crossing and to simplify the number of turning movements for people biking and walking making this area more predictable and increasing safety.
- complete bike and pedestrian planning along Division Street/TH246 from downtown to the City Limits and on Jefferson Parkway from TH3 to Spring Creek Road including connecting routes.
- completing policy update recommendations from Toole Design in the bike and pedestrian plan updates.
- evaluate planning policy including annexation, community facility siting, linking transportation to land use decisions, and incorporating metrics which measure walkability rather than vehicle movement.
Conclusion in my own voice
City staff are supposed to be the professional experts. As such, they must frame alternatives for the Council and the public using their professional expertise to distinguish options based on how each option will fulfill policy goals and meet safety or performance criteria. For this critically important project, knowing why an option is recommended needs to be articulated. For a project which is needed to fix prior decision-making, it is also important to learn how not to make similar expensive mistakes (in dollars and human life) again.
Thank you for the excellent analysis (and a look at how we got to where we are today).
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