Water is one of our most valuable natural resources. A combination of increased demand and trends toward less snowpack, more intense rainfall events, and/or longer, hotter, dryer summer conditions in many regions of the United States has water managers worried. A survey by the U.S. Government Accountability Office, now several years old, found that water managers in 40 of 50 states predicted water shortages in at least part of their region over the coming decade. If water access isn’t a national crisis yet, it soon will be.
With the threat of more water shortages on the horizon, many water managers are looking to creative technologies to increase the efficiency and availability of their water supplies. One key technology in their arsenal is managed aquifer recharge (MAR). MAR focuses on storing water when it is available (usually the wet season) in natural underground aquifers for use when it is not (usually dry summer months). A variety of MAR strategies may be appropriate depending on local geology and water needs.
In recent years, GeoEngineers team members have worked on MAR projects throughout the Pacific Northwest. GeoEngineers’ scientists are applying MAR technology creatively to meet the needs of diverse water users. Our water resource experts and teaming partners are working to improve the water supply for municipalities, industrial facilities, irrigation and natural stream habitats.
Industrial Water Reuse
In Quincy, Washington, GeoEngineers is working with the local utility to put industrial wastewater to good use. The utility’s state-of-the-art water treatment system will clean and filter industrial wastewater, and our team is developing a MAR system to store this water for later delivery and use—including using it to cool high-tech data centers. This system will reduce the city’s use of native groundwater, helping state water managers get in front of water level declines in the region. This first-of-its-kind project in Washington is demonstrates how a creative MAR solution can meet the challenges of sustainable long-term water supply.
Sustaining Agriculture
Our team is working for a large irrigated farm in north-central Oregon that’s facing long-term water supply declines in the basalt aquifer where they get their water. This MAR project will use abundant surface water to replenish the declining basalt aquifer. When complete, our client will be able to fully utilize their available water while slowing and eventually reversing aquifer water level declines for the benefit of local water users. In the long run this MAR project will even improve regional groundwater flow to the nearby Columbia River and provide a sustainable water source for farming operations near the river. This will be only the third such project in Washington and Oregon.
Improving the Potability of Existing Wells
West Richland, Washington, is facing problems with poor water quality from certain wells, making them unsuitable for drinking water. GeoEngineers is helping the city’s consultant engineering team evaluate the feasibility of using a MAR system to solve this problem. Fortunately, the city has access to high-quality surface water, and the proposed MAR system will replace poor-quality groundwater in a specific well with high-quality, surface-sourced drinking water. While displacement of low-quality water is common in coastal environments where MAR approaches can be used to displace or push back salt water, this project is the first of its kind in Washington. The clean water bubble built in the aquifer around the well will provide a new source of water for the city without the expense of drilling more wells and increasing regional groundwater declines. It will allow the use of existing wells that have been unusable because of poor groundwater quality.
Supplementing Stream Flow
Stream flows throughout Washington and Oregon have been affected by increased demand and climate stresses, and GeoEngineers has worked on multiple MAR projects with state agencies to address these challenges. GeoEngineers teams explored regional MAR projects that would store water and return it to streams when their flow needs augmentation and as a way to generate additional power during peak demand events. Our team has also used MAR in local watersheds to bolster shallow groundwater levels near streams in habitat enhancement projects, recovering lost spring creeks and baseflow.
These examples are just a taste of how we are using MAR to address a variety of water resource challenges. In all these MAR projects source water is collected only when its availability exceeds artificial and natural needs and stored in natural aquifers for passive or active recovery. When MAR well systems are designed correctly, they can be much more cost effective than surface reservoirs in large part because they take up less space. By using a well or two and/or small infiltration basins, these projects can store tens of millions of gallons of water without building dams, flooding valleys—and displacing people, their homes or livelihoods.
Because aquifers are more resilient to disasters such as earthquakes and storm events, ASR is also a valuable emergency water supply alternative. When surface reservoirs and source waters are affected by wildfires, flooding, or dam failures, water managers can fall back on their banked supply of groundwater.
Whether it’s industrial, municipal or watershed projects—we help our clients evaluate the feasibility of MAR solutions. Where conditions are favorable, we collaborate with water users and managers to design and implement MAR programs. In the coming decades, MAR technologies will likely become an indispensable tool for effective water management. I hope that municipalities and water managers are already evaluating these strategies—the long-term health of our communities may demand it.