In drought-stricken Central Texas, rain can be elusive. Hence my surprise when the sound of the rain jolts me awake at midnight. My brain struggles to place my location. Then it hits me. We’re stormwater sampling and it’s my turn to check the weather and real-time water quality data that determine our ability to collect the appropriate samples.
We’ve worked out an effective system to check the data in shifts so that only one person each hour has to wake up, and the rest of the team can get a few hours of consecutive sleep. At this point, we have been mobilized at our designated “home base” for 31 hours straight and the rain continues. This has been a long and challenging storm. Any opportunity to sleep is warmly welcome.
What feels like minutes later, I am awoken again, this time by the glowing cell phone light of my teammate, Jen Moreland, who has the data check-in shift after mine. Out of the silence, Jen whispers, “It’s time.” I can see from the water quality tracking chart on her phone that she is right. “Alright,” I say, “let’s do this.”
The Sampling Protocol
We take samples at three different stages of the storm, at five locations on the Comal River, and at seven locations on the San Marcos River. Our sampling protocols require us to collect grab samples directly from the flowing river into eight containers. This generally involves lying on our bellies in the mud, leaning over the edge of the bank, arms outstretched with vials in hand.
Occasionally, after several hours of regularly tracking the radar, the storm suddenly shifts away from the streams we need to sample, and the minimum springflow increase or water quality changes necessary for sampling do not occur. At that point we must pack up our gear and head home. Driving home, sometimes it seems as though the rain is all around us — everywhere except where we need it to be. On at least one occasion, we checked the weather again after arriving home to see that the storm had once again shifted, creating a sample-worthy event at the location we had just left.
The Need for Stormwater Sampling
Interestingly, it is not the rain that necessitates stormwater sampling but rather the absence of rain. The Edwards Aquifer is the primary source of drinking, municipal, agricultural, recreational, and industrial water for approximately two million people. An “artesian” aquifer (meaning that the water is confined under pressure) of karst limestone, the Edwards Aquifer is approximately 180 miles long and ranges from five to 40 miles wide. As part of the hydrological cycle, rain water and surface water enter the aquifer through fractures and conduits. Water moves downward under pressure in portions of the aquifer. This pressure forces water upward along geologic faults to the surface at the Comal Springs in Comal County and the San Marcos Springs in Hays County.
In 1956, a significant drought caused aquifer levels to decline to the point that the Comal Springs ceased flowing for 144 consecutive days. During this time, the fountain darter — a small freshwater fish found only in the Comal and San Marcos rivers — was extirpated from the Comal River system. Eventually, this fish, along with seven other aquatic species directly dependent upon the Edwards Aquifer for survival, became federally listed as threatened or endangered under the Endangered Species Act. The listing prompted a 1993 lawsuit filed by the Sierra Club against the U.S. Fish and Wildlife Service for failure to sufficiently protect springflows necessary for the survival of these species. The court ruled in favor of the Sierra Club.
SWCA is honored to be a part of the effort to protect the region’s threatened and endangered species and water supply. Our current work with regional water policy leaders and planners is helping protect local water resources and the species that depend upon them.
Regulating Use of the Aquifer
This lawsuit resulted in the creation of the Edwards Aquifer Authority — a groundwater management district tasked with regulating use of the aquifer — and a regional recognition that action had to be taken to balance the human and wildlife needs of the aquifer, or risk federal intervention through enforcement actions under the Endangered Species Act.
Recognizing the sensitivity and increasing tension surrounding this issue, in 2006 the U.S. Fish and Wildlife Service organized regional stakeholders to form a voluntary initiative known as the Edwards Aquifer Recovery Implementation Program (EARIP). The EARIP decided to pursue an incidental take permit to ensure compliance with the Endangered Species Act. Such a permit allows the “take” — which is incidental to, rather than the purpose of, an otherwise lawful activity — of federally listed species by non-federal entities.
In order to obtain that permit, the stakeholders negotiated, developed, and ultimately approved by consensus the Edwards Aquifer Habitat Conservation Plan (EAHCP) that would, among other things, mitigate and minimize the effects to listed species. The U.S. Fish and Wildlife Service issued the incidental take permit in March 2013 to five groups representing the efforts of the EARIP — the Edwards Aquifer Authority, the cities of San Marcos and New Braunfels, Texas State University, and the San Antonio Water System. Thus, the Edwards Aquifer stakeholders, through the EAHCP, have developed a comprehensive strategy to resolve a politically entrenched, decades-long conflict stemming from the challenges presented by the absence of rain. (Read an interview on the EAHCP process.)
SWCA and the EAHCP
Stormwater sampling is part of the EAHCP’s comprehensive water quality monitoring program to ensure that water quality is maintained at a level suitable for the survival of the listed species found in the San Marcos and Comal river systems. Since January 2014, SWCA has been conducting several types of water quality sampling, including the stormwater sampling efforts so bedeviled by the weather.
The EAHCP’s stormwater sampling program is far more complex than that for other purposes such as Stormwater Pollution Prevention Plan and Municipal Separate Storm Sewer System programs. Because those programs typically test for fewer water quality parameters, they require less water and are often collected from runoff outfalls (versus the EAHCP’s requirement to sample from flowing rivers), and in many cases automated samplers may be used.
The EAHCP’s program requires hand-collection of stormwater samples. Such sampling presents a unique suite of safety concerns, as staff must work in tricky conditions to collect the data. SWCA staff members have had the benefit of working with experienced Edwards Aquifer Authority staff and SWCA’s expert safety team to identify appropriate safety protocols such as the use of auto-inflating life jackets, strobe lights, swift-water rescue equipment, and general best practices for working in storm conditions.
In addition to hand-collecting samples from the flowing river during storms, SWCA conducts passive diffusion sampling, which involves leaving a small, shoelace-style device in the river for two weeks. Early on we found that most of the sampling devices were being moved by river users, getting dragged downstream, or being tampered with. To remedy this situation, SWCA staff designed and built containers from stainless steel silverware trays and concrete to hold the sampling devices in place in the river and provide evidence of any tampering, with waterproof tags identifying the monitoring equipment. Since we began using the weighted holders, our passive sampling success rate has significantly increased.
So far, 2014 results have shown that water quality is generally good. The EAHCP Science Committee is determining how many years of baseline data are necessary before any program adjustments might need to be made. The data we are collecting now will help provide an overall picture of how the aquifer systems function so that the Science Committee can identify patterns and trends. Study results also will feed into ecological models being developed, and over time water quality results may inspire additional research opportunities.
SWCA is honored to be a part of the effort to protect the region’s threatened and endangered species and water supply. Our current work with regional water policy leaders and planners is helping protect local water resources and the species that depend upon them. Of course, protecting local ecosystems is often much more complex than one or two activities, and the EAHCP is an example of just how multi-faceted Endangered Species Act compliance can be.
In addition to the water quality program, SWCA has worked on several other projects related to the implementation of the EAHCP. These include an invasive species removal and control program in the Comal system, dissolved oxygen management at Landa Lake (also in New Braunfels), and development of the inaugural annual report documenting compliance with incidental take permit terms and conditions.