Projects

Fish Pass tidal hydrology restoration

End Date: 07/31/15

Objectives

1. Remove and document tidal hydrology barrier at “Fish Pass”

2. Survey elevation and water flow speeds, salinities, and levels before and after hydrological restoration, to aid in design

3. Identify biological requirements and monitor changes induced by the opening of two barriers, “Fish Pass” and “Magnolia Inlet”

Methodology

Fish Pass will be opened and assessed, following the Gulf of Mexico Hydrologic Restoration Monitoring Parameters handbook. This will be conducted in collaboration with Calhoun County officials. The entirety of the current hydrological barrier is on County property and is composed of uplands. The project will be discussed in the context of associated project that is being permitted for a nearby location. Culverts or rip-rap will be placed for reinforcement as required.

Surface elevations will be surveyed with survey-grade GPS. Water flow speeds will be measured at both blockages before and after hydrological restoration. This work will supplement salinity and water level records, which are funded from an associated project. The depth and width of the barrier removal will be determined with this information.

Biological requirements and changes will be monitored around three distinct hydrological barriers, following the Gulf of Mexico Hydrologic Restoration Monitoring Parameters handbook. Two of these barriers will be opened during the time span of our monitoring effort: the “Fish Pass” barrier (funded by this source) and the “Magnolia Inlet” barrier (funded by a state-level match). Monitoring will include vegetation, aquatic nekton, and avian wildlife. Several 1m2 quadrats will be monitored for vegetative species and percent cover changes, on each side of each barrier. For nekton, drop traps and seine nets will be used following standard methodology of the National Marine Fisheries Service. Monitoring stations will be set up to observe avian habitat usage. The barrier removal design will incorporate this knowledge.

Rationale

A large expanse of salt marsh wetlands is disintegrating from Magnolia Beach to Indianola in Calhoun County. The wetlands are suffering due to a lack of tidal flow, due to multiple hydrological restrictions. As a result of anthropogenic barriers, the water is hypersaline, the vegetation is dying, and the marsh is eroding. Approximately 45,830 linear feet of shoreline is eroding and 473 acres of marsh have already been lost. Fish kills have occurred. Endangered Whooping Cranes have nested in this marsh. The Texas Ornithological Society and the Audobon Society own the adjacent Magic Ridge Sanctuary. Local citizens and tourists utilize this marsh for fishing, crabbing, and kayaking. The general area has multiple historical markers and trails that traverse the marsh, due to location of the nearby historical town of Indianola. The barriers need to be removed to restore full tidal flow and marsh health. Our long-term plan is to first remove the “Magnolia Inlet” and “Fish Pass” barriers, then eventually move to the nested “Zimmerman Road” barrier.

Results

Magnolia Inlet