MARSH MANAGEMENT MODELING OF BAYOU LACACHE WETLANDS

摘要

The Bayou Lacache Wetlands Project area located in southeast Louisiana is losing marsh due to intrusion of saltwater from adjacent bayous that extend into the Gulf of Mexico. The Project area is a closed system with constructed levees as boundaries. Flow into the system is controlled by gated culverts. Pumps and gated culverts control flow out of the system. Normally the entire area is under shallow flooding but a few pools become isolated during dry periods that become anoxic during the summer months. A two-dimensional hydrodynamic transport model of this area was developed as a management tool to assess the effects of subsidence, various pump drawdown and culvert gate operations alternatives on water level and salinity inside the marsh. This information was used to evaluate the potential for emergent vegetation growth to maintain a healthy marsh system. This paper will discuss the methodology and results of this modeling effort.