Water Well Journal
Issue link: https://read.dmtmag.com/i/557876
A quifer storage recovery (ASR) wells have been around the groundwater industry for decades. But as flooding and drought issues increase and the inability to secure freshwater sources decreases, governments and municipalities are reinvestigating the need for these types of well systems. So are we. Water Well Journal consulted two industry experts, R. David G. Pyne, PE, the president of ASR Systems LLC in Gainesville, Florida, and Peter Scott, a partner with the law firm Gough Shanahan Johnson & Waterman in Bozeman, Montana, and a former hydrogeologist. Pyne authored the book Aquifer Storage Recovery in 2005, available in the NGWA online bookstore. Scott will be pre- senting a session at the Groundwater Expo and Annual Meet- ing, December 15-17 in Las Vegas, titled "Aquifer Storage and Recovery." WWJ asked Pyne and Scott to discuss the basics of ASR systems and what the future may hold for them in the ground- water industry. Water Well Journal: What is an ASR? David Pyne: "ASR" stands for "aquifer storage recovery." It's storing water underground through a well in a suitable aquifer when adequate water of acceptable quality is avail- able, and recovering the stored water from the same well when you need it. P eter Scott: If you ask lots of people, you will get lots of answers. In my view, an ASR project is distinguished from other recharge projects by legal entitlement to withdraw stored water. In contrast to general recharge projects, the owner of an ASR project holds the legal right to withdraw stored water without regard to the priority date of other groundwater users in the same aquifer. Water Well Journal: Can you explain how the systems work? Scott: ASR projects divert water during times of the year when availability exceeds demand—usually during spring runoff—and stores it for use later in the year when demand exceeds availability—usually in late summer. Water is introduced to an aquifer either by infiltration (pas- sive recharge) or by injection (active recharge), and is stored for future withdrawal. The aquifer must be sufficiently porous to accept recharge, but not so porous the water migrates away too quickly. Inevitably stored water escapes over time, so commonly a formula is applied to determine the volume of available stored water as a function of time. Water Well Journal: Why is ASR important? Scott: A properly constructed ASR project provides the owner with an assured water supply, protected from possible curtailment by senior water users. Generally, a water user in need of an assured water supply has two options. One option is to purchase the senior water rights and change their purpose to meet the desired use. Be- cause the majority of existing senior rights are used for agri- culture, this typically involves taking land out of production. The other option is to create storage, either with surface impoundments or groundwater recharge. So, ASR can be a tool for improving critical water supplies while retaining agricultural production where that is deemed desirable. ASR SYSTEMS continues on page 28 ASR systems and their uses: A conversation with experts By Lana Straub SAVING WATER FOR A DRIER DAY WWJ September 2015 27 Twitter @WaterWellJournl An ASR well system residing in Orange County, Florida.