Better Off-the-Shelf Road Designs Needed From ConnDOT

ConnDOT's Highway Design Manual, the state reference book for engineers and designers, offers little in the way of complete streets designs. Advocates say it's past time for that to change.

ConnDOT’s Highway Design Manual, the state reference book for engineers and designers, offers little in the way of complete streets designs. Advocates say it’s past time for that to change.

Connecticut’s 2009 complete streets law requires that transportation projects receiving state funds consider all users of the road, and is considered one of the strongest laws of its type in the country. But when engineers and designers in the state sit down to begin designing a road project, they’re guided by the Connecticut Highway Design Manual (HDM), which contains outdated and ill-advised guidance that is incongruent with the state’s Complete Streets efforts.

The HDM is the standard road design reference book the state makes available to planners and engineers. It was written in 2003, and although revisions to the manual have been made as recently as last year, it does not reflect the complete streets law (in fact, it does not even include the term “complete street”). In its most recent annual report, the Connecticut’s Bicycle and Pedestrian Advisory Board (CBPAB) writes that “a comprehensive rewrite of the Connecticut Highway Design Manual is the single most significant improvement that can be made that would result in real and permanent changes to the mobility of the people of the State.”

Indeed, in many ways HDM remains rooted in car-oriented traffic engineering practices that fail to acknowledge the role of transportation in building safe, vibrant communities. In a telling passage, it describes traffic calming techniques as “typically limited to municipal streets”, though the state’s Complete Streets legislation includes state roads, and suggests that local governments that have developed their own traffic calming standards can use them “on a project-by-project basis.” The HDM does not even include designs for bike lanes. Instead, it directs readers to use a separate guide published by the American Association of State Highway and Transportation Officials (AASHTO) or reference an appendix to the state’s Bicycle and Pedestrian Transportation Plan. The only part of the HDM that references bike lane design is a series of quick-reference tables that describe five feet wide bike lanes as sufficient on multi-lane streets designed for cars going as fast as 45 mph (in a town center) or 50 mph (in suburban areas). Without a more robust bike lane section, Connecticut will be left behind as other parts of the country are increasingly using buffered or protected bike lanes that have more separation between cars and bikes.

Connecticut would hardly be the first state to revamp its road guidelines to reflect the pedestrian- and bike-friendly designs that local communities are demanding. The CBPAB cites Massachusetts’  Project Development and Design Guide as an example to follow. In the Guide‘s introduction, the authors write that one of the manual’s guiding principles is “to ensure that the safety and mobility of all users of the transportation system (pedestrians, bicyclists and drivers) are considered equally through all phases of  a project so that even the most vulnerable (e.g., children and the elderly) can feel and be safe.” The Guide includes bicycle and pedestrian guidance, and an entire chapter on traffic calming.

Localities have taken matters into their own hands as well. The National Association of City Transportation Officials publishes an Urban Bikeway Design Guide which outlines cutting-edge bike infrastructure designs that have proved their worth in places as diverse as New York City and Tucson, Arizona. New Haven has its own Complete Streets Design Manual, which includes guidelines for traffic calming. And last year, the Connecticut Conference of Municipalities released (with Tri-State Transportation Campaign) a “Complete Streets in a Box Toolkit” that includes a sample local policy, a primer on liability and links to design resources.

Since passage of the complete streets law, ConnDOT has taken some unprecedented steps, like announcing the first-ever road diet on a state highway. Now it’s time to rewrite the Connecticut Highway Design Manual so designers who want to build other balanced projects don’t need to reinvent the wheel with every project.

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