What is an Aquifer Storage and Recovery Well (ASR) and how do they benefit the region?

An Aquifer Storage and Recovery Well (ASR) is a type of well drilled deep into an aquifer. In the Jordan Aquifer, this is typically between 2500 and 2700 feet. These wells help manage supply and demand by allowing hundreds of millions of gallons of treated water to be stored underground for withdrawal during peak usage. Typically, ASRs are filled in the winter months when water usage is low and activated for service when usage spikes in the summer months. Additional resiliency is created during droughts or times of poor water quality by providing access to a large volume of high-quality water. CIWW and our member agencies have been withdrawing water from ASRs throughout this event to ensure that our 600,000 users have access to drinking water that meets all safe drinking water standards. This measure is being implemented in conjunction with various other measures we have been taking.

Central Iowa Water Works owns three ASRs:

LP Moon ASR, drilled in 2004, 2674 feet deep, 3MG Capacity

McMullen Treatment Plant ASR, drilled in 2006, 2518 feet deep, 3MG Capacity

Army Post Road ASR, drilled in 2016, 2525 feet deep, 3MG Capacity

Our member agencies also own ASRs: Ankeny owns three and Waukee and Grimes each own one. West Des Moines Water Works is constructing an ASR well, while the Urbandale Water Utility is completing the planning and design phase for one. Additionally, DMWW is developing a new ASR well for its system. 

A 300-million-gallon ASR amounts to the same volume as building 150 elevated towers, but at a fraction of the cost.