NewsDrop-June-2024

AQUIFER MANAGEMENT SERVICES (AMS) DIVISION OF THE EAA

By: Alyssa Balzen , EAA Geoscientist II

The EAA collects and assesses all water quality data, in addition to sam pling for the TWDB and supplementing analyses. Water quality sampling procedures and protocols have changed, and field parameters collected are the same, but multi-parameter sondes collecting the data have gotten smaller, lighter, and more accurate, with Bluetooth capabilities for data transfer, with easier maintenance. Water samples are collected from springs and wells all over the region (Figure 5 & 6), and the number of water qual ity analytes sampled for has increased by eightfold, with detection limits in parts per billion or parts per trillion. These analytes include a much broader range of ionic constituents, including anions, cations, trace elements and Figure 5. Gizelle Luevano, Lead Hydrologic Data Coordinator, and Faith Goddard, University of Texas San Antonio STEM Graduate Student, collecting water quality samples from Comal Springs 7, New Braunfels, Texas.

Figure 6. Alyssa Balzen samples a well in New Braunfels, Texas.

isotopes, along with potential emerging contaminants such as PFAS and microplastics.

Water samples are also collected as part of specific research projects in areas that affect the aquifer, such as at the Field Research Park (FRP), a 151-acre property owned by the EAA. Samples are collected at Trinity Aquifer wells at the FRP to gain insight into recharge and inter-aquifer flow characteristics, and are tested for major cations, anions, trace metals, dissolved inorganic carbon, total suspended solids/total dissolved solids, alkalinity, PFAS, total coliform, E. coli, and stable isotopes.

Figure 9. Emily Thompson uses a cell phone to navigate an easement property.

Figure 10. Thomas Marsalia using a cell phone to navigate an easement.

Applications on cell phones and handheld devices are used to access highly detailed GIS-based maps, of easements showing current GPS location, specific points, property information, and marked roads (Figure 9). Land

management techniques promoting aquifer recharge and sustainability are tested at the FRP for potential use on easement properties, and new conser vation easements are sought out to increase protections over the aquifer.

AQUIFER SUSTAINABILITY

NEXT GENERATION The FRP is key to the EAA’s Next Generation initiative of ensuring the Edwards Aquifer is sustainable for future generations. Through modeling, conservation practices, and contaminant tracking, we can implement and identify techniques at the FRP that can be applied across the region for the benefit of the aquifer.

Figure 8. Total number of acres conserved through EAA conservation easements over time.

Figure 7. Using a map to navigate a conservation easement property.

Taylor Bruecher, Geoscientist II

Then: The City of San Antonio’s Edwards Aquifer Protection Program (EAPP) was created when San Antonio voters supported a one-eighth-cent sales tax in 2000—and subsequently renewed in 2005, 2010, and 2015— to protect land over the Recharge and Contributing Zones of the Edwards Aquifer. One conservation easement was acquired by the EAA and San Anto nio Water System before the EAPP began, on the original 4,700 acres of Government Canyon State Natural Area.

Now: Easement inspections are conducted on over 170,000 acres of land on more than 140 properties protected by EAPP conservation easements (Figure 8).

Easement inspections were completed using paper maps, a compass, and a camera to note specific points on a property for comparison year to year. Handheld GPS devices paired with paper maps and a digital camera came next, but the GPS was not particularly accurate because it connected to fewer satellites, so topographic maps, creeks, and fence lines were used for navigation (Figure 7).

Special thanks to Hakan Basagaoglu, Bryan Anderson, and Thomas Marsalia for providing their expertise and assistance on this article.

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