(Photo by Tony Welch)

By Tracy Record
West Seattle Blog editor

As noted here last week, the citywide bridge audit – ordered by City Council Transportation Chair Alex Pedersen after the sudden West Seattle Bridge closure – will be presented to councilmembers this week. In advance of that, the audit document is out today, along with SDOT’s response. We’ve just read it. First, so you can read it too, here it is:

(You can also see it on the city website.)

The audit, by the City Auditor’s Office, counts West Seattle’s city bridges as 20 separate structures (see page 31), 8 rated “good” as of last year, the other 12 (including all sections of the high bridge) rated “fair,” the middle of three categories in the federal rating system. “Fair” is how a majority of the city’s bridges are rated:

But the audit does not dive into specific conditions of specific bridges – it is an overview of the program in general, as explained:

We analyzed 77 vehicle traffic bridges that are owned and maintained by SDOT. These bridges have a median age of 70 years.

According to 2019 Federal Highway Administration pavement and bridge condition performance measures, although Seattle has a high number of poor and fair bridges (based on the federal rating system of good, fair, and poor), this is comparable with peer cities around the country. Nevertheless, even bridges in fair condition, like the West Seattle High Bridge, can require major, unexpected closures.

Over the last decade, a larger percentage of Seattle’s bridges have gotten worse compared to those that have gotten better. Over the past 14 years, the average amount SDOT spent on bridge maintenance was $6.6 million annually. 3 However, according to knowledgeable SDOT officials, the City is not spending enough to keep its bridges in good condition and avoid costly future repairs.

… The number of Seattle’s bridges that are in poor or fair condition is concerning for two reasons. First, several of the largest and busiest bridges that connect communities across Seattle are not in good condition, which means they are at an elevated risk of unexpected closures that could affect thousands of people. For example: the University Bridge on average carries 36,000 vehicles daily and is rated poor; the Magnolia Bridge on average carries\ 20,000 vehicles daily and is rated poor; and before it was closed this year, the West Seattle High Bridge on average carried 108,179 vehicles daily and was in fair condition.

Most of SDOT’s bridges are in fair condition but, over time, the condition of the overall bridge portfolio has gotten worse. During this time, the percent of total bridges in good condition has declined from 38 percent to 29 percent (see Exhibit 5). According to federal guidance, SDOT should be working to preserve good bridges in good condition to maintain the structural reliability of bridges and avoid future costly repairs. SDOT is not meeting this goal and only 22 out of its 77 bridges are in good condition.

The audit also notes that while SDOT should have a higher budget for bridge maintenance, it hasn’t spent what it has:

Since 2006, SDOT has spent 93 percent of its budget for bridge maintenance. From 2006 to 2019, Seattle budgeted $98.5 million for bridge maintenance and spent $91.9 million (see Exhibit 7, dollar amounts have been adjusted for inflation). As Exhibit 7 shows, the budget did not always align with actual expenditures on a year-by-year basis. Some of this is to be expected. For example, in 2008 SDOT underspent their bridge maintenance budget because they were saving funds for a large bridge painting project. This large painting project, the University Bridge, was completed in 2009. This use of funds that carryover from one year to the next occurs when the funding for these projects comes from the City’s Capital Improvement Program budget. SDOT officials told us the reason for the underspend between 2016 and 2018 was primarily because they did not have enough staff to perform planned maintenance activities.

SDOT estimates annual maintenance expenditures should be equivalent to one to three percent of the total replacement cost for the fixed assets being maintained, or, for bridges over 60 years old, a minimum of $34 million per year.

In a response letter that’s also included with the audit document, SDOT director Sam Zimbabwe blames the underspending on “that maintenance program delivery fluctuates based on work accrual and staff capacity.”

The audit also contains a critique of “some legacy practices and information gaps [that] hinder its ability to properly keep the bridge portfolio in a state of good repair,” with a declaration that “SDOT lacks critical information for developing a strategic bridge preservation program, including an assessment of the level and mix of staffing resources needed to maintain their bridges.”

One example reveals that SDOT bridge-maintenance staff doesn’t spend all its time on bridge maintenance:

One such practice is using bridge maintenance workers to perform reimbursable work, unrelated to SDOT bridges, for other agencies. SDOT estimates that 20 percent of their bridge maintenance staff capacity is dedicated to performing reimbursable work for other divisions within SDOT, other City departments, or other local governments. This means that two out of every ten hours of SDOT’s bridge inspection and maintenance crew work are not being used on the upkeep of Seattle’s bridges, but to help supplement the department’s budget. SDOT told us they lack the money to fully fund their bridge maintenance staff without the revenue from\ reimbursable work, which means they would need
to make reductions to stay within budget.

Plus, the audit says, “SDOT does not have information on what staffing levels are needed to support essential bridge maintenance, making it difficult to plan for and complete this work.”

The audit also observes that “SDOT does not currently calculate the useful life of its bridges in a precise way, which hinders its ability to efficiently respond to bridge maintenance needs.”

In SDOT’s reply, director Zimbabwe contends that “the issues that led to the closure of (the West Seattle Bridge) do not appear to be the result of any deficiency in our bridge maintenance program.”

Overall, the SDOT response also says it’ll take three years – until the end of 2023 – to make changes/additions responding to all the audit’s 10 recommendations, 9 of which the department says it fully agrees with.

The presentation of the audit is scheduled for Wednesday morning’s meeting of the council’s Transportation and Utilities Committee, 9:30 am; the agenda includes information on watching the meeting and signing up to comment. Meantime, here’s Councilmember Pedersen’s news release responding to the audit, and here’s the SDOT Blog post with how the department summarizes the audit and its own responses.