As snowplow drivers are catching up on their sleep, other road crews are getting ready to emerge from weather-forced hibernation to bring a traffic slowdown to a road near you.
Spokane County began last week seeking bids to rebuild the bridge on Valley Chapel Road over Spangle Creek, south of Spokane. Drivers will have to detour around the construction planned between Elder and Spangle Creek roads from about April to November.
The 1923 bridge is due to be made new again, county bridge engineer Neil Carroll said.
“That bridge has a sufficiency rating of 8,” Carroll said. “A brand-new bridge is 100, and 0 is on the ground.”
The bridge was built according to earlier construction standards, he said. “A number of the old bridges had a 50- or 60-year design life,” Carroll said. “In my view, there is going to be quite a crunch – certainly locally and big-time nationally – with the number of bridges that need to be replaced.”
Some 2,700 bridges in Washington and Idaho have been ranked either “structurally deficient” or “functionally obsolete,” according to federal statistics – though bridges often serve for years with such designations and are not by definition unsafe.
Seven bridges overseen by Spokane County have been assigned weight restrictions, including the old Interstate 90 bridge on Appleway Road at Stateline.
The county hopes to start work replacing that 1939 bridge by 2010, Carroll said.
That bridge, which has a 10,000-pound restriction limiting traffic to small cars and light trucks, is worrisome because contractors used the same design as the Spokane Valley’s Harvard Road bridge, which failed in 1992.
Most of the money for bridge replacement comes from the federal Bridge Replacement Program in the form of grants administered by the state.
But there’s a limit to that money.
“I think it would be safe to say that there was such a rapid escalation in construction costs that the program got overcommitted,” Carroll said.
In the early 1990s the county could have replaced the bridge on Valley Chapel Road for about $50 to $70 a square foot. Now it costs between $220 and $240 a square foot, he said. The bid estimate is from $952,000 to $1.23 million.
With dwindling resources, county officials must put a premium on bridge inspection. The county has one full-time employee doing nothing but inspecting about 170 bridges and another who spends about a third of his time on inspections, Carroll said.
“By doing that, you have an awareness of your inventory and where to best put your resources,” he said. “It’s not tolerable to have half a roadway fall into the river one night.”
Inspectors last fall determined that a bridge on Chattaroy Road over Dragoon Creek had a severe “scour” problem. It wasn’t built deep enough to keep the creek from undermining the concrete foundation, Carroll said. Weight restrictions were put in place and one of the two lanes was shut down.
“We had to do some emergency work to keep the road open,” he said.
Other bridges with weight restrictions include the bridges on Sunset Highway and Christensen Road over Deep Creek; the bridge over Thompson Creek on Newman Lake Drive; and the bridges on Little Spokane Drive and Deer Park-Milan Road over the Little Spokane River.
“The needs aren’t going away, and the traffic volumes are increasing,” Carroll said.
Lower speed limits
For quite a bit longer, commuters from Coeur d’Alene must drive 55.
In December, the Idaho Transportation Department lowered the speed limit in westbound lanes of I-90 from the Northwest Boulevard exit to the State Route 41 exit in Post Falls. It was a safety precaution prompted by concerns over potholes on three bridges, ITD spokeswoman Barbara Babic said.
Starting in early May, the area covered by that speed-limit reduction will expand from the Sherman Avenue exit to the Washington state line, she said. In areas where road crews are resurfacing westbound lanes, the speed limit will be 45 mph, she said.
Just as commuters reach Spokane, they have more obstacles to avoid.
While road construction season is still weeks away, some downtown streets already have some closures.
Post Street between Riverside and Main avenues will have southbound traffic detoured. In addition, the west side of Post Street north of Riverside Avenue has no parking or pedestrian traffic until the end of 2008 to accommodate construction crews working on the Grant building.
Spokane Falls Boulevard east to Riverpoint Boulevard has been reduced by one lane as construction crews there work on a new nursing school, Spokane city streets spokeswoman Ann Deasy said.