At STV, our purpose to make communities better extends beyond our planning, design and program and construction management capabilities. In fact, there are occasions where we have to roll up our sleeves and get into the thick of a project site to make a difference and produce a better outcome for our clients and the communities we serve.
Our findings from a fish species inventory that we conducted at the Upper San Felipe Creek in Del Rio, TX, were recently published in a peer-reviewed article in The Southwestern Natural academic journal. This effort was produced in collaboration with the University of Houston Clear Lake and other agency partners.
As part of the San Felipe Creek Improvement Project (C-7-10), our team monitored the Devils River minnow (Dionda diaboli) population while a contractor worked to stabilize the creek’s eroded banks. For this program, our job was very hands-on – which isn’t always the case. We had to clear the fish from the construction area and monitor for any harm to the species during the installation of the coffer dams, which were put in place to create temporary water barriers during construction.
The San Felipe Creek is an important piece of ecological infrastructure in southeastern Val Verde County. The creek is the sole source of drinking water for the City of Del Rio and Laughlin Air Force Base and the stream has long been a primary recreation attraction for Del Rio residents.
The creek is also home to many unique animal species – chief among them the Devils River minnow which has been listed as a threatened species by the U.S. Fish & Wildlife Service since 1999.
Due to the importance of water quality in the creek, both as the sole source of drinking water for area residents, as well as the primary habitat of these unique animal species, a regional water quality planning study that would identify opportunities for protecting water quality throughout the drainage basin was a necessity.
As part of our work, coordinating the installation of the dams in the fast-moving, spring-fed stream posed several challenges. The strong flow of the creek – which can typically range from 50-to-90 million gallons per day – kept us at the site for more than 20 days so we could best execute on this task. But despite these complications, our team successfully placed the coffer dams and pumped out water to clear the construction zone to protect the native fish species.
We also had to account for water runoff during storm events and coordinate with Texas Parks and Wildlife to maintain water, so it continued to flow through the creek for the fish during construction to maintain the ecosystem. In the end, we were able to confirm the presence of 36 native fish species, which contributed to our findings.
Data collected detailing the creek’s biodiversity adds valuable knowledge to the scientific community and provides a clearer understanding of the aquatic habitat and species distribution in the area.
STV’s biology and environmental services– including species analyses; wetland and water delineations; migratory bird surveys; and permitting – continue to be enlisted by clients across Texas to perform wetland delineations and marine mammal presence/absence surveys for proposed infrastructure projects.
Our work is often behind the scenes, but projects like this showcase the role biologists play in ensuring sustainable construction practices. We were proud to contribute to both the preservation of threatened and endangered species and to the broader understanding of the current state of fish assemblages within San Felipe Creek.
