Wednesday, August 22, 2012

The collective results of hundreds of individual decisions to suspend lawn and landscape irrigation around Carroll — and the arrival of some rain in the last two weeks — have improved the level of the city’s aquifer, the source of potable water for residents and businesses

Having reached a recent low of 84 feet below surface on July 17, the aquifer level on Monday had climbed back to 79 feet, 7 inches below surface. At some point after 86 feet below surface the pumps break suction, creating the real potential for faucets to run dry in the city.

“The aquifer has been in pretty good condition, surprisingly,” said Public Works director Randy Krauel.

The situation has stabilized to the point where city officials are measuring the aquifer level once every three days instead of daily.

On July 9, the city pumped 1.9 million gallons of water. That compares with about 1.2 million in the winter months. On Sunday, the city pumped 1.065 million gallons.

Krauel said it is clear water customers have used common-sense and responded to the situation — without the imposition of voluntary or mandatory water-conservation measures.

Carroll residents see others in the Midwest similarly affected by the drought and are acting, Krauel said.

“Maybe the social consciousness is raised within the city,” he said.

While the aquifer level is encouraging, the city is far from free of serious concerns — and won’t be until probably next spring, if then, Krauel said.

“We are also entering a time of year when customarily we don’t receive a lot of rainfall,” Krauel said.

It takes 10 inches of snow to do for the aquifer what 1 inch of rain can. And the rains don’t immediately benefit the aquifer 70 feet below ground, Krauel said.

Longer term, the city is looking at measures to reduce threats of water shortages. The city has eight wells along the Middle Raccoon River between Grant Road and U.S. Highway 71. The wells reach down 150 feet to 203 feet.

On April 23, the city signed a contract with JEO of Carroll for a $19,500 study of potential new wells. Some preliminary results have led to meetings between JEO and the city with test drilling planned after harvest.

Carroll is at the southern end of the Dakota Aquifer where it is more challenging to find water. It’s not as simple as just sending down a drill and connecting a pump.