Removing roads key to keeping Portland's water source clean

by Michael Milstein, The Oregonian

High on the slopes of Mount Hood in the Bull Run River drainage, where Portland gets its tap water, heavy machinery is moving earth and blacktop.

The trackhoes aren't laying pavement, as crews did during the logging boom of the 1970s. They're dismantling miles of old logging roads and reshaping the slopes.

The deteriorating roads, built atop thousands of dump-truck loads of unstable fill, are environmental time bombs that could slump and collapse. That would send dirt cascading into crystalline Bull Run reservoirs that provide Portland some of the purest drinking water in the country.

If that happened, the Portland Water Bureau would have to switch temporarily to other water sources or undertake more expensive treatment.

"The whole fill would go downhill and become part of water-quality problems," said Todd Parker, district hydrologist for the Mount Hood National Forest, which encompasses Bull Run.

Parker and others from the Forest Service, Water Bureau and environmental groups toured the work last month. "It's so exciting to see this happening," he said, looking at the reshaped slopes.

Once at odds over logging in the watershed, the Forest Service and the Water Bureau now have a partnership. The Water Bureau will maintain some roads for access to its water system and for firefighting. The Forest Service will take out the rest.

The agency has "decommissioned" and actively removed 45 miles of road within the 65,500 acres that drain into Portland's water supply. Now crews are taking out the final 18 miles of road in the critical area.

The work is funded with a slice of the $40 million that Congress allocated to deal with deteriorating roads in national forests. U.S. Rep. Norm Dicks, D-Wash., championed the "Legacy Roads" money, backed strongly by Oregon's congressional delegation.

That money also is paying for removal of 245 old rusting culverts that forest officials worry could become blocked in storms and cause roads to wash out.

The Forest Service has shut down another 78 miles of road that pose no erosion risks so nature can reclaim them. The agency terms that work "passive decommissioning."

All told, the work has made a serious dent in the 346 miles of road that once criss-crossed the Bull Run. Environmental groups say that's a good start, but that much more work remains.

"The Legacy Road fund was a sign that protecting watersheds is a congressional priority," said Alex Brown, executive director of Bark, a fierce opponent of logging and an advocate for restoration on Mount Hood. "We just hope it continues to be a priority. Bull Run is only one of many drinking watersheds in the Mount Hood National Forest."

Decommission more
The Forest Service plans to decommission another 45 miles in the Bull Run watershed but outside the area that flows directly to Portland's taps. It lacks the money for that, however.

The work is expensive, but it pays off, said Gary Larsen, Mount Hood forest supervisor. Once the roads are gone, the Forest Service no longer has to spend maintenance money from its shrinking budget to try to keep them from falling apart in Oregon's unforgiving weather.

"When we decommission, it lets us stop that long-term stream of maintenance costs," Larsen said. "We don't have to keep coming back and checking for problems."

Bull Run was once a logging battleground. The Forest Service allowed clear-cutting of about 16 percent of the watershed, although the only logging since 1983 has been the salvage of trees blown down in a storm. In 1996, Congress banned logging in Bull Run -- but the roads remained and have become an increasing burden.

Deteriorating culverts intended to drain runoff under the roads can instead collapse or become clogged, causing water to back up and then wash the roadbed downhill. At one site above the uppermost reservoir, crews removed about 600 dump-truck loads of fill to find a culvert that was near the point of collapse.

"It was just waiting for the right event to fail," Parker, the hydrologist, said. "If we're not here the moment the culvert plugs, that's where it's all going," he said, pointing down toward the reservoir.

Reviews before money
Mount Hood National Forest managers completed the lengthy environmental reviews and approvals for the project before money was available to pay for it. That allowed them to move forward with decommissioning contracts quickly once the money arrived.

Some other forests that didn't move as quickly may have similar contracts postponed as the Forest Service scrounges for money to pay for fighting severe wildfires this summer.

Decommissioning the roads involves breaking up the pavement and making the slope match the natural contour. Crews spread rocks and logs across the surface, giving shrubs and trees a chance to take hold and colonize the ground in coming decades.

"All of this work increases water quality and reduces the sediment into our reservoirs," said Edward Campbell, resource protection and planning director at the Water Bureau. "This is really about protecting our water quality."

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