Kennewick hopes to test a new aquifer system for storing Columbia River water next year. Construction is underway on a pump station near Southridge High School that will allow the city to put treated river water into the Wanapum aquifer and to pump it back into the city's water system.
Tapani Inc., which was hired to build the $1.6 million pumphouse and pipeline for the project, expects to finish its work by Jan. 1, said Kennewick city engineer Bruce Beauchene.
The $4 million project is a partnership with the Washington State Department of Ecology, which is providing about $2.4 million.
It is one of a few pilot projects in the state trying out the idea of storing water in an aquifer during winter months when flows in the river are high and demand is lower, and then using the water during the summer when water is more scarce and demand is up.
Officials say it's a way to provide water for future growth while keeping water in the Columbia River during critical times. And it's a way for the state Department of Ecology to try to create new water rights.
A vertical turbine pump from the well house will reach part of the Wanapum aquifer, a deep body of water that runs under many places in Eastern Washington, including a good portion of Benton County such as Red Mountain and Horse Heaven Hills. Also under construction is a monitoring well in another location.
A pipeline is being extended from a water main on West 36th Avenue to the pumphouse, Beauchene said. The project includes 310 feet of 16-inch piping.
River water that has already been treated will be pulled out of the water main and stored in the aquifer. When the water is needed, the city can pump it out and treat it with chlorine for use in the Southridge and Canyon Lakes areas for any normal city potable water uses.
While the city doesn't have any water rights that allow it to pump from that aquifer, it can use it to store water that it does have the right to use under the so-called quad-cities water right it shares with Pasco, Richland and West Richland.
City officials hope to start pumping water into the aquifer in March, Beauchene said. However, the exact timing and amount of water has yet to be determined.
The goal is to be able to store water underground in time to withdraw it in early summer.
"We are looking forward to the next phase of the project," Beauchene said.
That's when the city and Ecology will fully evaluate the feasibility of storing water underground, he said.
Once storage begins, Kennewick will perform tests to help determine the impact on the aquifer, any water loss, mixing of the groundwater and treated river water and the cost of operating the system.