A road diet, rechannelization, safe streets redesign, complete streets project or whatever you want to call it: It works.
Troy Heerwagen has created an excellent interactive infographic over at his Walking in Seattle blog that shows how consistently effective Seattle’s long history with low-cost safe streets redesigns has been. Many of our city streets were overbuilt during a 20th Century era of road engineering that put the high speed movement of cars above safety for people. Often, this manifested in the form of streets with too many lanes and/or lanes that are too wide, both of which lead to speeding and increased likelihood for injury and death. Four lane roads might work on a rural highway, but they don’t work in urban neighborhoods.
As Seattle works towards Vision Zero, we are going to need hundreds more miles of these redesigns. So it’s great that the city already has so much experience to build on.
Seattle was among the first cities in the nation to figure out that the same number of vehicles could travel on a much safer, less stressful three-lane street (one lane in each direction with a center turn lane) and has been redesigning streets in this style since the 70s. As time goes on, their designs have improved and most often now include better crosswalks and bike lanes, creating a more complete street.
These redesigns can vary widely in cost depending on how far the changes go. Simply repainting a street to have a safer design can cost in the neighborhood of $50,000 – $100,000 per mile (including community outreach). That might sound like a lot of cash, but in transportation infrastructure terms it’s pennies.
Repaving, improving sidewalk curbs, installing crosswalk islands or raised crosswalks, building protected bike lanes and transit islands, etc. all add to the cost and benefits of the projects. For example, though the safety data is strong for many of Seattle’s past road diet projects that included bike lanes, those bike lanes were often only paint and located uncomfortably close to busy traffic and opening car doors. Protected bike lanes cost a bit more, but the extra separation from general traffic appeals to many more people.
City estimates for street redesign projects with protected bike lanes range widely in cost from $350,000 to $5 million per mile based on experiences in other cities and the planned Roosevelt Way bike lane. Costs increase in denser areas with more traffic signals and repaving needs or if the city opts for better crosswalks or more attractive barrier options, like permanent planter boxes instead of plastic reflective posts.
When choosing projects for safety upgrades, Seattle is prioritizing dangerous streets based in large part on collision and injury data. Unfortunately, we have a lot of that data. The following streets were prioritized for quick action in the Vision Zero plan released last week:
- Rainier Ave S (new meetings just announced)
- Lake City Way
- SW Roxbury Street
- 35th Ave SW
- Banner Way
The city has also highlighted the following streets to “plan and develop long-term multimodal improvements.”
- Delridge Way SW
- East Marginal Way
- Yesler Way
- Greenwood Ave N
- 3rd Ave
- Beacon Ave S
The city will also start work this year on improving safety on 23rd Ave in the Central District and Roosevelt Way as part of larger repaving projects there. North Broadway on Capitol Hill is in the design phase as part of a planned streetcar extension and will continue the complete street design currently south of Denny Way.
And, of course, the city plans to build more than seven miles of protected bike lanes and 12 miles of neighborhood greenways in 2015, as outlined in the Bike Plan Plan:
But Seattle’s supply of dangerous, overbuilt streets remains plentiful. The city is headed in the right direction, but we need to significantly boost investment if we’re gonna get on track to eliminate traffic deaths and seriously injuries by 2030.