Why Bridging the Gap Alone Can’t Eliminate Seattle’s Maintenance Backlog

Earlier this year SDOT provided new estimates of our maintenance backlog and annual maintenance needs to the Citizens Transportation Advisory Committee and the Seattle City Council. Many folks have asked why these figures have changed so dramatically since 2006, prior to passage of the Bridging the Gap Levy. 

During development of Bridging the Gap, SDOT estimated the deferred maintenance backlog to be over $600 million. This figure was based on very limited data about Seattle’s transportation system inventory and condition. It also excluded major bridge replacement needs such as the Magnolia Bridge, which was estimated at the time to cost over $200 million. Today’s one-time cost estimate to bring all parts of the transportation system into good condition is about $1.8 billion, a significant increase. 

How did this number increase so dramatically? 

Bridging the Gap was never supposed to fill the gap:  Despite the fact that Bridging the Gap doubled funding for maintenance of Seattle’s transportation system, it was never expected to fill the maintenance funding gap. In fact, with BTG and consistent levels of base funding, it was only anticipated to fill about 50 percent of the need for annual maintenance. This has allowed SDOT to stabilize the condition of some assets and improve maintenance cycles, but still leads to an increase in the maintenance backlog as needs are not fully met.  

Costs Continue to Rise while Base Revenues Decline

Costs Continue to Rise while Base Revenues Decline

Base maintenance funding has gone down:  Bridging the Gap was developed in response to decreases in transportation funding, including the gas tax, prior to the Great Recession. Before the recession it was expected that base levels of city funds dedicated to maintenance would stay level. Due to the economic downturn, general fund revenue dedicated to transportation has declined almost 25 percent and gas tax revenues have continued to fall. This drop in base revenues for transportation has reduced base maintenance funding, boosting the rate of increase in the maintenance backlog.

Increasing costs to fix the transportation system:  Despite the recession, construction costs for transportation projects have continued to rise. Since 2003, WSDOT’s transportation construction cost index has risen 68 percent, with almost a 30 percent jump during 2006, right when Seattle was deciding whether to move forward with BTG. Costs for asphalt paving materials rose even faster, up 80 percent since 2003, with a 34 percent jump in 2006. This rapid rise in costs to construct transportation projects has increased the estimated cost to eliminate the maintenance backlog. 

Seattle’s transportation system has grown but funding hasn’t:  Bridging the Gap didn’t just fund maintaining the transportation system Seattle owned in 2006. It also had funds, over 30 percent, for making improvements to the system, increasing the overall size of it. Since 2007 Seattle has added 70 school crossing beacons, 20 new radar speed signs, 90 traffic cameras, and almost 20 message signs to help folks navigate our streets and increase safety. We also added signs, hundreds of street trees and new sidewalks, and striped new crosswalks, bike lanes and sharrows. Entirely new systems have been added to the transportation system, such as parking pay stations, the South Lake Union Streetcar and King Street Station. All of these improvements require maintenance and operations to keep working, but funding hasn’t gone up at the same time. This also adds to the backlog.

SDOT has better data and more accurate costs today:  Bridging the Gap allowed SDOT to do more than just go out and fix streets or build improvements to the transportation system. It allowed SDOT to put in place an asset management system to track all of Seattle’s transportation system elements and their condition. Prior to Bridging the Gap, SDOT’s information on its system tended to be old or incomplete. Today SDOT has better information, including maintenance requirements for much of its system. By using its asset management system, SDOT can better estimate the cost of carrying out necessary repairs. All of this leads to more accurate estimates of transportation needs.

Despite rising costs and reduced revenues, Bridging the Gap and SDOT have delivered

Since 2007, SDOT has made progress in maintaining and improving Seattle’s transportation system using Bridging the Gap revenues. Because Seattle voters approved the levy in 2006, SDOT has been able to begin fixing bridges in poor condition, prune trees more often, and improve sidewalk and stairway maintenance. We’ve also been able to increase safety and mobility for all modes with pedestrian, bicycle, transit, and active traffic management improvements, and stabilize the overall condition of arterial pavement in Seattle. Though only halfway through the life of the levy, it is clear Bridging the Gap and SDOT have delivered for Seattle.

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  1. says

    I appreciate the work that SDOT has done to holistically quantify the condition of Seattle’s streets and their maintenance needs. Planning and implementing street maintenance a basic fiduciary responsibility of City government.

    However, it is politically unrealistic (with our current leaders and voters) to ever raise $1.8B for city street maintenance. SDOT needs to look a bit more critically at the maintenance backlog and cost estimates. What could be trimmed while retaining a functional system? Does the Magnolia Bridge need to be completely replaced, or can it be retrofitted?

    The status quo of transportation planning in this country is based on assumptions of ever increasing traffic, and ever increasing road & lane widths to accomodate faster traffic with less “delay.” (example: see Spokane Street Viaduct project) Does Seattle want this? Does Seattle need this? The answer is no – traffic counts are stagnant and declining. Seattleites increasingly expect auto traffic to play nice with the sidewalks, bike lanes and bus stops we use for transportation.

    Why should we be maintaining streets with asphalt, which has increased in cost dramatically, instead of concrete, which all over Seattle has demonstrated a lifespan of nearly 100 years?

    Please come up with a realistic maintenance backlog cost estimate, and a realistic financial plan to maintain our streets in perpetuity (i.e. sustainably). (See strongtowns.org for guidance) It will be expensive, but we need to build the political will to maintain our streets, while modifying them in a cost-neutral way to better accomodate bicyclists and pedestrians.

    • SDOT Blog says

      Thanks for sharing your thoughts on this. You should know that the full $1.8 billion covers all parts of our maintenance backlog, including streets, bridges, retaining walls, signals, signage, walkways, etc. As Bridging the Gap does not provide all the funds needed to address the complete backlog, we have prioritized to address the most important and most pressing needs first.

      In 2009, average daily traffic in Seattle was approximately 900,000 vehicles, which is a lot to accommodate. (The Spokane Street Viaduct carries 72,600 vehicles in daily traffic, so that work is an important investment for automobiles, freight and transit.) We are, however, investing in bike, pedestrian and transit options to provide people choice for traveling around the city. So we share your perspective about creating a transportation system for the future that is sustainable and offers travel options.

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