There will be no discernible difference in the amount of water flowing in from the Ross Barnett Reservoir to the amount flowing out of the project area to the downstream channel. The project will be required to meet minimum outflow levels required by permits and regulations. Emergency gates have been added to the weir to ensure that minimum levels are always achieved even in extreme drought conditions. With no perceptible decrease in water flowing downstream from Jackson, and with two-thirds of the Pearl River Watershed actually south of Jackson, the project should have no impact on salinity levels in the Gulf.

Furthermore, the project would result in beneficial impacts on water quality by eliminating the use of chemical sprays used to remove vegetation inside the current levees during maintenance work. In addition, the proposed project includes removal of existing unpermitted solid waste disposal sites in the floodplain and removal and capping of an existing hazardous waste site, which should reduce future contamination from these existing sources.