Egery Flats sits on the western edge of Copano Bay near the mouth of the Aransas River. In 1945, when Farm to Market Road 136 was constructed, two culvert systems, each consisting of two 30-inch round culverts, were installed to allow water to flow in and out of Egery Flats. Over time, the flow through these culverts has become restricted enough to impact water quality and habitat, which has resulted in the conversion of over 100 acres of estuarine marsh and habitat to open water since the 1950s. While FM 136 connects local communities and is a favorite spot for roadside fishermen, crabbers, and birders, Egery Flats has deteriorated greatly since its construction.
The Coastal Bend Bays & Estuaries Program (CBBEP) received a grant from the National Fish & Wildlife Foundation’s (NFWF) Gulf Environmental Benefit Fund for the project. The project replaced the old 30-inch round culverts with three 3’ x 6’ box culverts at each of the two locations. These new culverts have increased water flow greatly and restored critical hydrology. This restored hydrology had immediate effects as salinity levels in the area began to drop, and the water quality began to improve for more than 600 acres of emergent marsh, submerged vegetation, and tidal flats at Egery Flats. Prior to the start of construction, CBBEP worked with Mission-Aransas National Estuarine Research Reserve (MANEER) at the University of Texas Marine Science institute and TPWD to collect valuable preconstruction data, including porewater salinity and vegetation monitoring. These data will be valuable in the evaluation of future projects. The evaluation and ongoing data collection will last for 3 years beginning with the completion of the project.
“This project has shown incredible success since the installation of the new culvert systems in the fall of 2018. Salinity levels within Egery Flats continue to work towards equalizing with those of Copano Bay, and water quality standards continue to improve,” commented Adrien Hilmy, Project Manager for Coastal Bend Bays and Estuaries Program. Adrien continued, “We look forward to seeing the continued success and growth of emergent marsh within the project site through improved water quality and grass plantings.”
In early October, contractors began harvesting and planting 40,000-plus native cordgrass plants that will cover approximately 8 acres. This effort is expected to take two to three weeks to complete. As the planted cordgrass takes hold and grows, it will then naturally expand, collect sedimentation, and restore acres of critical emergent marsh. This portion of the project is being funded in a large part through $70,000 in funding provided by CCA Texas and Building Conservation Trust.
Successful projects are often successful because of a strong partnership base that works hand in hand. The Egery Flats project has several partners including: National Fish & Wildlife Foundation, Coastal Bend Bays and Estuaries Program, Texas Parks & Wildlife, US Fish & Wildlife Services, Building Conservation Trust, Coastal Conservation Association Texas, Mission-Aransas National Estuarine Research Reserve, University of Texas Marine Science Institute, and Texas Department of Transportation. All these partners have and will continue to play a vital role through the completion and post monitoring effort of the project.Habitat restoration and creation is a vital component to insuring healthy and bountiful coastal resources for the future. CCA Texas and BCT are committed to continuing their support to projects along the Texas coast for generations to come. This support would never be possible without the continued success of the grassroots efforts of CCA Texas volunteers across the state and supporters within the communities in which CCA Texas chapters exist. CCA Texas and BCT are continuously seeking project and funding partners for habitat efforts. For more information about CCA Texas or BCT, please contact John Blaha at (713) 626-4222 or [email protected]
It began in 2018, completed in spring of 2019.
One thing I would like to add which I did not mention on the phone, the porewater salinity takes a long time to return to lower levels compared to surface water salinities. So, while we have already seen improvement following the culvert replacement, we expect to see a steady recovery for years to come.