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Wednesday, Dec. 03, 2008

Deeper wells defy drought

As state dries up, company goes extra 40 feet for water

Armando Blas gripped a 3-foot-long mud-covered metal drill bit as a long drill shaft spun into place from above. The tall rig holding the shaft stood 42 feet above the ground from the back of a truck whose engine was running.

On Tuesday afternoon the rig groaned away on a cold, empty lot just north of Merced.

Beside the rig, two muddy trenches filled with water. As the drill sunk deeper into the ground, a pump sucked up the muddy liquid from the trench and shot it back down the drill hole to lubricate the two-day well-drilling process.

After pushing down past mud and rock and sand, the well will tap 300 feet below the Valley floor. At that depth it won't catch any of the chemical runoff that floats at the top of the water table, said Joe Silveira as he watched Blas at work.

In the midst of a drought, with water tables continuing to drop and farms and cities with their never-ending thirst for water, Silveira's Atwater-based Quality Well Drillers has been working overtime to drill ever-deeper holes in the soil of the Central Valley.

For Silveira's 12-man crew and its five rigs, this has been a nonstop year. So far, they've drilled about 300 wells, said Silveira. Until Thanksgiving, he employed one agricultural well driller going 24 hours a day.

"We've been really busy the last 15 years," said Silveira. "Now, because of the drought, we're doing about 30 percent more than usual."

His company's good fortune has come from a sinking water table and a long dry spell.

With a three-year drought, the already declining levels of the water table haven't been replenished.

But for as far back as Silveira can remember, the groundwater has been dropping in the Valley.

"Around Atwater we've seen drops of 40 feet in the water level," said Silveira as he leaned against his truck watching the drill dig into the soil.

According to the state's Department of Water Resources' California Ground Water Bulletin, Merced's groundwater levels have sunk 30 feet since 1970.

The story is similar across much of the Valley. With the drought getting worse, the only place to get water is from the ground.

Merced Irrigation District's general manager, Dan Pope, said it has had to increase pumping with reservoir levels almost 50 percent below average. This growing season they ran 170 pumps. Typically, they have 40 or 50 pumps running.

"This thing's going to get really serious if we don't get some snow and some rain soon," said Silveira.

Silveira is no stranger to drought. He first got into drilling during the 1976-77 drought, the worst in recent history. A couple of his friends were working on rigs at the time, and he got a job. Eventually, he bought some rigs of his own and has been sinking holes ever since.

Besides the deeper depths, wells are pretty much the same. After drilling down beneath the water table and into sand, a 5-inch PVC pipe is placed down the hole. The perforated pipe is encircled in small rounded beach stones from Monterey that filter the water. Finally, crews cap the well with clay that prevents runoff from going down the hole.

"If it's done properly they don't need another filtration system," said Silveira.

But with a sinking aquifer and prolonged drought, one day there may be no water to filter.

Reporter Jonah Owen Lamb can be reached at (209) 385-2484 or jlamb@mercedsun-star.com.