As sea level rises, coastal cities and towns are growing increasingly concerned that fresh water sources used for drinking water, wastewater treatment, agricultural irrigation, and industry could be fouled by saltwater intrusion. Saltwater intrusion occurs when higher sea level forces saltwater inland at the surface or underground through porous rock and sand. When the salt water reaches fresh water intakes on rivers or underground wells, the fresh water become unfit for human consumption and most other uses.
According to a study published in the Journal Nature, millions of Americans live in coastal communities at risk of losing access to fresh water due to saltwater intrusion. KCRA in San Francisco aired a report last week that examined the threat saltwater intrusion poses to the state’s Central Delta waterways.
As sea level rises, it threatens to push salty ocean water up into delta rivers and estuaries that provide drinking water to 27 million California residents as far away as Southern California. The water is also used to irrigate the Central Valley’s farmland.
Sea level rise isn’t the only contributor to the saltwater intrusion problem. The West’s ongoing mega-drought is also drawing down river levels, which could potentially hasten the inland movement of saltwater from the sea. The only way to prevent this is by releasing more water from reservoirs or the construction of a barrier to block the saltwater, which California is trying on the West False River.
The threat to real estate owners and buyers in all of this is that any community that loses access to fresh water is a community in distress. This could cause real estate values to plummet. Clearly everyone involved in coastal real estate needs to be aware of where their fresh water comes from and how safe it is from saltwater intrusion.
As sea levels rise, many coastal communities are concerned that salty ocean water will contaminate water wells that provide fresh water to millions of residents. The loss of a fresh water source would be devastating to a city or town. Trying to find new sources, if it’s even possible, could be expensive. This issue should be of concern to real estate buyers in coastal communities.
The saltwater intrusion problem isn’t theoretical. For example, in 2007 researchers at Florida State University surveyed water planners to predict what would happen if seas rose 6-to-18 inches by 2057. Half the planners were concerned that their wells would be threatened by tidal salt water traveling up coastal rivers where water intakes and wells were located.
Kenneth Miller, an earth scientist at Rutgers University, told YaleEnvironment360 this week that the combination of heavy development on barrier islands with low elevations and broad exposure to ocean water puts New Jersey and other locations around the world at risk of saltwater intrusion.
South Florida residents could get a taste of the future this summer. The densely populated region is experiencing a deepening drought that’s forcing water managers to enforce watering restrictions and move water around in canals to prevent wildfires in the Everglades. As fresh water supplies are drawn down, there’s the risk that saltwater will try to fill the void, which could put wells at risk.
Whether salt water intrusion becomes a problem remains to be seen, but the situation certainly exposes a situation that many real estate buyers in coastal areas are not aware of that’s only going to get worse in the years to come. Clearly, knowing how secure a community’s supply of fresh water, or even a private well, is from saltwater intrusion is an important point to consider when buying property in areas near the sea.