With over a quarter of blocks missing sidewalks and a backlog of street projects, the city is contemplating adopting a transportation impact fee as a way to help pay for new infrastructure needed to handle growth.

Last week during a meeting of the Seattle Sustainability and Transportation Committee, Councilmember Mike O’Brien instructed city staff to begin developing a transportation impact fee schedule for these one-time charges paid by new development.

Impact fees were authorized by the 1990 Growth Management Act, and today most urban jurisdictions have adopted some kind of impact fees for roads or parks. The City of Sammamish has adopted some of the highest transportation impact fees, charging new single-family homes close to $15,000.

Seattle has considered impact fees for years. A 2015 staff report recommended further study of park and transportation impact fees, but competing priorities delayed the work. Councilmembers sitting on the Sustainability and Transportation Committee received an update on the progress last week.

These funds must be used within ten years of collection and spent on projects that provide capacity for future growth. Impact fees cannot be used to pay for existing deficiencies, but they can be used for transit or greenway projects, according to Kendra Breiland, a consultant from the firm Fehr and Peers.

“When you start thinking through all these parameters, many cities have started moving towards recognizing they can spend these funds not just on those traditional auto capacity projects, but we can spend them on much more multimodal projects,” Breiland told the committee.

She said transit projects could include off-board fare payment, transit signal priority, rapid ride corridors, in-lane bus stops or curb bulbs.

Breiland said that generally, the fees are based on the number of afternoon peak-hour trips each new development is estimated to generate. She also pointed to a nuance in state law that allows cities to charge impact fees on completed projects, just as long as they are still providing capacity for future growth. However, Breiland added, many jurisdictions don’t choose to do this.

City staff said the next step is for the Sustainability and Transportation Committee to review a project list the consultants and city staff assembled, after which Fehr and Peers would create and present a fee schedule. Action by the Council could happen as early as this summer.

The city webpage states a “draft impact fee proposal for consideration by the Mayor and Council” will include a list of projects that could be funded, fee rates and implementation legislation. According to the site, a park impact fee proposal will be developed after the Parks Development Plan is completed.

Breiland said a maximum defensible rate would be presented and the City Council could select that rate or set it lower.

Councilmember Rob Johnson, not convinced impact fees were a good solution, wanted to also study other tools cities are using to pay for transportation projects.

“The anxiety that I feel about impact fees is just generally the inconsistency of revenue generation,” Johnson said during the committee meeting. “There could be years where we are generating a heck of a lot in impact fees and there could be years where we are generating very little, and that consistently causes me to have some long-term budget concerns, which is part of the reason we need more progressive tax reform at the state level.”