As we all know, most of life on Earth needs water on a more or less constant basis. Humans have relied on living near natural water sources or have developed technologies to bring water where we want it. Today, our water infrastructure is a complex network of lakes, aquifers, and reservoirs leading to all manner of aqueducts, from rivers and canals to ditches and pipes.
Finding and transporting water is often difficult; ensuring its quality is a trickier task, especially in an era of climate change. On April 12 and 13, Caltech's Linde Center for Science, Society, and Policy (LCSSP) hosted a workshop to address this challenge. Titled Innovations in the Science & Policy of Water Quality Measurement, the workshop was part of the center's mission to provide a forum for research and debate on topics at the intersection of science and society. The workshop included policymakers, economists, environmental engineers, biologists, agronomists, and others who met to discuss key challenges in measuring and maintaining an adequate clean water supply.
Hannah Druckenmiller, assistant professor of economics and a William H. Hurt Scholar, specializes in natural resource policy and helped to initiate the workshop. Water-quality measurement, she says, "is an area where a lot of exciting science and measurement is happening, but it's not always being used in water policy. If you talk to water-quality managers and regulators, they say that scientists often come to them with the latest new gadget or idea, and though these things work well in the lab, they may not work in practice. We want to encourage communication between scientists and managers at the inception of new research and design initiatives rather than after these have already been developed."
"There has been a long history at Caltech of interest in studying water and water quality," says Mike Alvarez, Flintridge Foundation Professor of Political and Computational Social Science and co-director of LCSSP. According to Druckenmiller, the Water and Ecosystems group at JPL, which Caltech manages for NASA, has also been active in water-quality measurement because "harmful algal blooms are a major water-quality factor that you can see from space."
Algal blooms and agricultural runoff pollution—what is known as "nonpoint source pollution"—was one of three main areas of research addressed at the workshop. "This is one of the first areas where remote sensing has really influenced decision making and management decisions in the environmental sphere," Druckenmiller says. Researchers from Caltech, JPL, the Environmental Protection Agency, and Virginia Tech spoke on this topic in the morning on April 12 after an introductory discussion on policymaker perspectives with speakers from the California State Water Resources Control Board, Environmental Systems Research Institute, and the Metropolitan Water District of Southern California.
A second area of research the workshop addressed was sea-level rise and saltwater intrusion—impacts on water quality directly associated with climate change. Along with a scientist from JPL's Sea Level and Ice group, researchers from the University of Maryland and the University of Hawaii explained how farmers in Maryland and the general population in Honolulu are assessing the amount of seawater intrusion in their freshwater supply.
Managed aquifer recharge was the third area of research covered in the workshop. "Managed aquifer recharge involves thinking about how we can reinfuse wastewater into natural underground aquifers," Druckenmiller says. "Recycling water and increasing our total supply sounds great, but this process comes with a whole host of water-quality challenges. Untreated wastewater can contaminate clean water in aquifers. If you repeatedly recycle water, you risk concentrating any pollutant." These challenges were discussed by panelists from the National Science Foundation, the Orange County Water District, and Rohde Environmental Consulting.
The workshop concluded the morning of April 13 with a discussion of how social scientists can most helpfully analyze data on water use and quality to inform environmental decision making, and a lengthy conversation about how participants could keep the science-and-policy collaboration initiated by the workshop moving into the future.
"A lot of us were surprised by how much overlap there was in the issues that come up for water-quality researchers looking at the problem from different angles," Druckenmiller says. "Sometimes with interdisciplinary conferences, people can be talking past each other rather than to each other. But in this workshop we had very good communication across disciplines."
Alvarez agrees. "What makes an event like this a success is when we bring diverse groups together, we talk science, we talk policy, and we come out of the encounter with a shared sense of purpose and some really cool research ideas that we can begin to implement."
Druckenmiller hopes, in particular, that workshop participants can initiate something like the instrumentation surveys periodically undertaken in other scientific disciplines. "You survey a group of scientists working in a broad field and try to figure out what are the most important instruments worth investing in," Druckenmiller says. "Nothing like this exists right now in water-quality research, but we are hoping that we can take stock to determine the highest-priority measurement issues and research questions that we should collectively be tackling."
