We were awestruck by the recent studies published by researchers at UC Irvine and NASA that showed how quickly groundwater supplies in the U.S. are declining. We reached out to graduate researcher Sasha Richey at UC Irvine to learn more about the study.

1) How did the idea for this study come about?

Our research group under Professor Famiglietti really pioneered the use of the GRACE satellites to look at how groundwater storage is changing in time. I was most interested in how the combination of natural dynamics (eg drought) and human impacts (eg pumping) impacted the health of the aquifers. We highlight aquifers that have depleting storage supplies, but we’re really the first to try to understand the long term sustainability of the aquifers by incorporating storage in a stress study. The more I dug the less I found about concrete estimates of groundwater storage globally. I was blown away about how little we know about such an important resource.

2) What are some of the risks facing people who live in areas with dwindling groundwater supplies?

We often think of groundwater as a back up water supply or a “buffer” as we say in the second paper. When there isn’t enough surface water, we trust groundwater to be there to close the gap. We are showing that we can’t always do that now. It’s going to get more and more expensive to pump groundwater and supplies dwindle and water quality decreases.

3) Would you be able to further explain the link between climate change and distressed basins?

Climate change is expected to make some areas wetter with a greater tendency to flood and other areas drier with a tendency to drought. Neither is good for distressed basins. As we see in California now, we pump more groundwater during drought times which puts increased stress on the aquifers. Increased flooding is bad because the water is coming in so fast that it rushes away before we can capture it in reservoirs or let it recharge the groundwater. Stressed systems occur when we are pumping more than can be replenished and climate change will likely decrease that replenishment.

4) What can average people do to address this issue in their daily lives?

People can start most simply by just recognizing the existence and importance of groundwater. We often forget about it because we can’t see it and just assume it will be there. That’s not necessarily true any more. What we really need to do is better monitor and manage our groundwater systems but that’s not going to happen until we fully recognize its importance.

5) Are there any plans to follow up on the study?

Yes! I’m starting as a post-doctoral researcher at Washington State University where I plan to better define what “sustainable groundwater use” means and also to work toward better quantifying groundwater storage. That said, we need a community wide effort both within the hydrologic community and also state and federal support before we can adequately assess our resources. We know how to measure storage, but we need the funds and support to do it.

6) What are some of the challenges associated with collecting accurate data on groundwater levels?

Collecting data on groundwater is expensive and time consuming. These large aquifers cover such a huge land area that to really measure and monitor them well, we need many observation points. Groundwater is very heterogeneous, that is to say that the properties of the aquifer can vary widely within even just a short distance. We can’t just assume that what is happening at one observation point is the same as what is happening even just a mile away. There is a great opportunity for “citizen science” however to monitor groundwater. So many people use groundwater from a personal or community well, and almost all of those people have cell phones. My dream is that every time someone draws from a well, they could upload that information to a central database that we could use to monitor the systems.