A Climate Risk: The Threat of Saltwater Intrusion

by | Nov 14, 2023 | Assessments

New Orleans and southern Louisiana are not the only places that face the threat of saltwater intrusion. Many other communities across the United States, especially coastal communities, are threatened by saltwater intrusion. Like New Orleans, the rising sea level and higher tides allow sea water to inundate further onto the mainland. These saline flood events increase corrosion to infrastructure in developed areas, flood farmland, and kill crops in less developed areas. Saltwater damage has been implicated in the 2021 collapse of the Champlain Towers South in Surfside, Florida.

Additionally, increased development and use of groundwater in coastal communities is accelerating the movement of saltwater from the sea to underground aquifers. Communities that rely on groundwater for their water supply are also facing significant threats. Coastal communities from Long Island, New York and south along the Atlantic seaboard to Miami are looking for ways to address the encroachment of saltwater into the water supply. Since removing salt is expensive, the approaches so far have concentrated on limiting water use and recycling grey water.

Mitigating the impact of saltwater intrusion may include maintaining and restoring wetlands; preserving coastal land; restricting development; stormwater management; and groundwater use restrictions. Implementation of these mitigation strategies will likely occur through the adoption of new environmental regulations.