The scene may not have looked extraordinary, but in the annals of Seattle street maintenance it was, perhaps, a notable event. As the sun beat down on the blacktop at Rainier Avenue South and South Charles Street on Monday afternoon, a worker pushing a sprayer that was a bit bulkier than a shopping cart laid down fresh, white crosswalk lines.
What made the 8-inch-wide stripes unique was not their location or configuration, but the material coming out of the sprayer's nozzle. The Seattle Department of Transportation typically uses latex paint for striping street lanes, and more resilient "thermoplastic" to mark crosswalks. The material in the sprayer was Methyl Methacrylate, or MMA, an ultra-tough, high-priced road paint. The three crosswalks at the T-shaped intersection were the first ones the city has striped with the substance.
"The material is very expensive, but it lasts a long time," said the city's traffic engineer, Dongho Chang, as he stood on the street corner, watching two SDOT employees wearing coveralls, reflective vests and respirator masks mark one of the crosswalks. This year, SDOT made plans to test MMA on the crosswalks at the intersection striped on Monday and at another location in the city's downtown core. If the material holds up, and the costs pencil out, then the agency might look to use it more widely for painting crosswalks in the future.
Two members of an SDOT striping crew mark a crosswalk on South Charles Street, at the intersection of Rainier Avenue South. Photo: Bill Lucia
Crosswalk restriping is one component in the city's ongoing battle to maintain and repair Seattle's 1,677 linear miles of streets. The three crosswalks at the intersection on Rainier are among 560 that SDOT plans to mark this year using funds from the Bridging the Gap levy. Voters approved the property tax measure in 2006 to provide $365 million for roadwork.
SDOT committed to re-marking 5,000 crosswalks during the levy's nine-year term, which expires at the end of 2015. If the agency meets its 2014 goal, then by year's end SDOT crews will have restriped 5,289 since the levy went into effect.
Currently, SDOT has rated the quality of 5,253 city crosswalks. As of Tuesday, 3,122 were in good condition, 689 were fair and 1,442 were rated poor.
Not fade away: A crosswalk on Northeast 80th Street, near Lake City Way, shows its age. Photo: Bill Lucia
"I would say that restriping of crosswalks is one of the most frequent requests I receive," said City Councilmember Tom Rasmussen, who chairs the Transportation Committee. "There is probably a list of 5,000 other crosswalks from the public that we haven't painted yet," he added. "There are a lot of needs we have to meet."
Despite those frequent requests and the fact that 27 percent of the pedestrian pathways SDOT has rated are considered poor by the agency's own standards, Chang challenged the suggestion that the city's crosswalk markings were in rough shape overall, and said he was proud of the agency's restriping efforts. "We're making our crosswalks visible," he said.
The thermoplastic material the city commonly uses for crosswalk stripes tends to wear out in four to six years. In locations with heavy traffic and concrete pavement, Chang said it can fade away in just one year. Some crosswalks SDOT put down in the early days of Bridging the Gap may have already been erased by car, truck and bus tires.
By comparison, striping done with MMA can last up to 10 years, according to Chang. The downside of the product is the cost, which can be eight to 10-times as much as latex paint.
Chang could not provide an immediate dollar estimate for how much the crosswalks at Rainier and Charles would cost. But a 2010 Federal Highway Administration report to Congress stated that the price per foot for an MMA similar to the one SDOT was applying could be between $0.80 and $1.65 for a 4-inch-wide stripe. Comparable thermoplastic would cost as little as $0.47 to $0.58 per foot, based on the figures in the report.
But less frequent restriping could cut down on other expenses. And Chang notes that that there are also less tangible benefits as well. For instance, fewer traffic delays for drivers waiting on striping crews and less sprayer noise annoying residents.
Apply-A-Line, Inc., one of the larger pavement-marking outfits on the West Coast, has been using MMA on jobs that require a more tenacious road paint for about 15 years. According to company President Mike Liljestrom, in busy areas using MMA can make a lot of sense.
"It's hard as nails," he said. He added that for high volume intersections in Seattle, "it's pretty easy to justify, instead of getting out there once a year to restripe."
Everett, where Chang used to work as a transportation official, began using MMA on some streets about five years ago.
Ryan Sass, the city engineer there, said the up-front expense of using the material can be offset by savings in labor costs and other materials that result from the less frequent need for refreshing street markings.
But the city only uses the tougher substance on road segments that will survive at least six to eight years. For surfaces that need to be replaced more often, Sass said MMA "would be a waste because it would outlast the pavement we attach it to."
Seattle does most of its crosswalk and road striping in-house, though contractors mark lines on some newly constructed roadways. SDOT has three striping trucks and the MMA sprayer that was on-site at Rainier and Charles. The crew at that site included six people, two working the sprayer, two laying out the lines, and two controlling traffic. According to SDOT spokesperson Rick Sheridan, a crew can mark between five and 12 crosswalks per day.
Annual number of crosswalks SDOT has re-marked using Bridging the Gap funding. City traffic engineer, Dongho Chang said the number has declined since the first three years of the levy because restriping was front-loaded to take care of pressing needs at that time. Source: SDOT
Crosswalk and lane striping expenditures under the Bridging the Gap program were about $1.5 million in 2013 and will be roughly $1.4 million in 2014.
From Lisa Quinn's perspective, marking crosswalks is a smart investment. Quinn, is executive director of Feet First, a nonprofit that advocates for improved pedestrian safety. "It just indicates that this is a place for people," she said. Crosswalks, Quinn added, seem to be "things we can easily implement year after year without taking a whole lot of money."
"It's a basic thing they should be incorporating into maintenance," she said, referring to SDOT.
Recent studies demonstrating whether marked crosswalks are an effective way to improve pedestrian safety are scant and older research is sometimes conflicting.
An often-cited Federal Highway Administration report from 2005, authored by University of North Carolina researchers, raised questions about the efficacy of crosswalks at locations without stop signs or traffic lights.
The researchers looked at five years of pedestrian crashes at 1,000 marked crosswalks and 1,000 unmarked crosswalks. They found that on two-lane roads there was no difference in the rate of vehicle-pedestrian collisions in the places with marked crosswalks. On multi-lane streets, with more traffic, vehicle-pedestrian crashes increased in places where crosswalks were marked, rather than unmarked.
But the report emphasized that their results do not apply to crossings with traffic signals, stop signs or other traffic-calming measures. And current FHWA pedestrian facility guidelines point to marked crosswalks as a way to improve safety for people on foot. "Poorly maintained crosswalk markings," the guidelines say, "may not provide the visibility necessary to warn motorists of the street crossing."
Pedestrian fatality rates in Seattle have been low compared to other West Coast cities in recent years. And in May, the group Smart Growth America published an index that ranked large metropolitan areas in the U.S. based on pedestrian danger. The Seattle-Tacoma-Bellevue region was the 49th most dangerous out of the 51 places on the list.
Still, dozens of people get hit and injured by vehicles in Seattle each year. And SDOT's 2012 traffic report notes that 315, or roughly 65 percent of the vehicle-pedestrian collisions that occurred that year, took place at marked or unmarked crosswalks.
For SDOT's Chang, the markings are about much more than just paint. He believes the crosswalk at Rainier and Charles, where there is a stoplight, will incentivize more people to cross at that location. And when more people are using a crosswalk, it raises awareness among drivers that there are pedestrians in an area.
"It's not the striping," Chang said, as the crew continued spraying MMA onto the surface of Rainier Avenue. "It's how people who are living and working in this area start using this crosswalk."
Check out Crosscut’s City Beat page for all the news and commentary about Seattle.