Jim Winterle does his job by the numbers, lots of numbers to be exact. He is the director of modeling and data management for the Edwards Aquifer Authority, and produces water level forecasts for the Edwards Aquifer Habitat Conservation Plan (EAHCP).

Winterle’s work is central to the EAHCP in the goal of protecting the endangered species at the Comal and San Marcos Springs in a drought of record. This work revolves around implementing conservation programs that will help keep the springs flowing even in extended dry weather. Winterle calculates the probability for program success by running flow simulations in the current Edwards modeling software.

“We have the statistics on how the Edwards Aquifer water levels dropped during the drought of record back in the 1950s,” Winterle said. “Those numbers form a baseline of sorts on which to compare how the Edwards will react to modern pumping during dry weather. We model full pumping of permits, then begin to reduce pumping with drought stage reductions, then add in EAHCP conservation programs like ASR Leasing and VISPO to the model. With each model run, we can give planners and program managers a good idea of what kind of results each of the programs will produce.”

That is critical information because the cost for programs spanning the 15-year EAHCP permit period can run in the millions of dollars. Additionally, the Incidental Take permit from the U.S. Fish and Wildlife Service, which gives the Edwards Region the ability to continue to pump water during a drought of record, is based on EAHCP participants’ enacting conservation measures at certain triggers as water levels and spring flows drop.

“We know there are many decisions based on our work, so we are constantly updating the Edwards model to ensure we provide the best data possible to EAHCP leaders,” Winterle noted. “Because you can’t see the Edwards underground, we rely on the numbers that create the flow model and how we run those numbers for direction. At the same time, we’re also refining how we calculate recharge because that number is key to the various program triggers in the Habitat Conservation Plan. The recent National Academy of Sciences report underscores that we’re headed in the right direction. But we know the work of creating a better model will always be ongoing.”

For more information on Flow-Protection measures, such ASR Leasing and VISPO, please visit http://www.eahcp.org.

EAHCP Steward is published by the Habitat Conservation Plan Implementing Committee

The Edwards Aquifer Habitat Conservation Plan e-newsletter, “Steward,” is published to highlight the efforts underway to protect theComal and San Marcos Springs and ensure a healthy habitat for the threatened and endangered species.

Winterle Work Accomplished by the Numbers

Jim Winterle, Director of Modeling and Data Management for EAA