Wildfires Threaten Urban Water Supplies, Long After the Flames Are Out

Wrangling a 25-foot-long tube of straw up a steep hillside studded with charred pine trees, three volunteer workers placed it in a shallow trench that had been dug along the slope.

Locked in place with wooden stakes, the sausage-like tube was part of an effort to avoid a potentially large and long-term problem with the drinking water for hundreds of thousands of people to the east. The tube, with others above and below it, should help prevent the hillside, made unstable last fall by a large wildfire, from choking the water supply with sediment when the thunderstorms known as monsoon rains arrive as expected this summer.