Water Level, Salinity, and Elevation Data at Turtle Bayou Mitigation Area of Bayou Sauvage National Wildlife Refuge, 2024

Bayou Sauvage National Wildlife Refuge (BSNWR) is an urban refuge in southeastern Louisiana that has been altered extensively due to human impacts. As a result, the hydrology of the impounded (interior) marshes within the BSNWR has been disrupted due to obstructions such as spoil banks, levees, and water control structures that affect the gradient and fluctuation of water surface elevation (water level) impeding water exchange between open channels, lakes, and the adjacent marsh. Changes in hydroperiod have led to marsh loss and damage resulting in altered flooding and salinity regimes. Marsh mitigation is a restoration technique designed to replace damaged marsh with newly created restored marsh that has been implemented to benefit such habitats. The U.S. Army Corp of Engineers (USACE) completed a mitigation project within the Turtle Bayou area of the BSNWR with a target of creating 126 acres of intermediate marsh with an elevation of 0.15 meters (NAVD88). This mitigation has the potential to enhance the area by providing beneficial marsh habitat to the refuge, but monitoring is essential to evaluate success. The U.S. Geological Survey, in collaboration with the USACE, began monitoring in February 2024 at four sites across a hydrological gradient within the mitigation area and at a real-time water level gage outside the mitigation area. Data sondes were used to collect continuous water level and specific conductance data.