Reno-Carson freeway nearing completion

For most of the time crews have been building the I-580 project between Reno and Carson City, the work hasn't really affected the average commuter.

And except for the huge Galena Creek Bridge, most of the construction was pretty much invisible to drivers on the existing highway.

That changed about two weeks ago, when the north Washoe Valley turnoff to Bowers Mansion was closed down and lanes of freeway through the valley shifted to one side. Now commuters must slow and wind their way among barriers designed to funnel them past crews working to tie the overpass leading toward Bowers into the existing, old Highway 395 through Pleasant Valley and connect the new I-580 freeway into the freeway running through Washoe Valley.

It's one of the final pieces of a $500 million puzzle that has consumed eight years of construction and which, when finished, will provide commuters with an uninterrupted and much less congested drive between Reno and Carson City.

The centerpiece of the 8.5 mile extension of I-580, the Galena Creek Bridge, is nearly complete. The 1,725-foot long bridge, which soars 320 feet above Galena Creek, is the most expensive single element of the project, costing more than $95 million.

It's also the most controversial, with Southern Nevadans calling it a waste of scarce highway money when they have to battle gridlock every day.

Ground was broken on that bridge in November 2003, but work halted when the original contractor pulled out in a dispute over how to build the structure.

Now, the "falsework" - the steel support system used to hold the bridge up while it was being built -- is coming down, and the foot-thick concrete deck that cars and trucks will drive on is being poured. When complete, it will actually be two parallel bridges, each supported by a 670-foot concrete arch to carry more than 30,000 cars a day.

While the roadway will be striped for two lanes in each direction, NDOT officials say there is room for three each way once the traffic justifies it.

Within two weeks, according to resident engineer Brad Durski, a conveyor system will begin removing the massive earthwork that supported that falsework and restore Galena Creek to its original condition.

For more than two years, the creek has been flowing through a 44-foot-diameter tunnel at the base of that earthwork.

The other eight bridges along the route have all been completed and, beginning from the northern end of the project, the entire roadway is being paved. Nevada Department of Transportation spokesman Scott Magruder said crews - some 300 every day - are working to get as much of the paving and other work done before winter as possible. He said the entire project is to be finished next summer.

But NDOT Engineer Rick Nelson said earlier in the project that the new route won't completely replace the existing highway because big trucks will be barred from the bridge on very windy days. They'll still have to drive through Pleasant Valley.

The Galena Bridge wasn't the only challenge that engineers faced in designing the project. The second-largest bridge, the 918-foot Galena Forest Bridge, carries the freeway through a geothermal field at Steamboat Springs. Engineers had to build the bridge columns on pads with limestone footings to prevent caustic geothermal water and steam from corroding the concrete pilings. That structure too is now being paved.

Another issue engineers faced was that the bridges could suffer serious icing problems during bad winter weather. The solution: Four of the bridges, including Galena Creek, have automatic de-icing systems that spray a chemical across the road to prevent slippery conditions from causing accidents or forcing closure of the route. To further improve traction, the concrete roadbed itself is being grooved.

Magruder said the new route will not only relieve congestion by increasing capacity; it will be safer by reducing accidents south of the Mount Rose Junction. As a bonus, with no stoplights or on- or off-ramps, and a speed limit of 65 instead of 50 mph through Pleasant Valley, it'll shave five minutes or more off the trip.