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Buying a Home in Imperial County, CA: The Salton Sea, Lithium Valley & the Imperial Fault

The Salton Sea is a genuinely severe, worsening environmental crisis — and the county is simultaneously home to a fast-moving lithium industry and one of the state's most active fault zones.

Imperial County, in California's far southeastern corner along the Mexican border, is defined by intensive irrigated agriculture (the Imperial Valley), extreme summer heat, one of California's most active fault systems, and a genuinely severe, well-documented environmental crisis at the Salton Sea — alongside a fast-emerging lithium and geothermal industry that's reshaping the county's economic base.

What’s the transfer tax in Imperial County?

Imperial County's rate is flat across the entire county at $1.10 per $1,000 of consideration, with no city imposing an additional surcharge — including El Centro, which is chartered but still applies the standard $0.55 city rate.

Brawley, Calexico, Calipatria, El Centro, Holtville, Imperial, and Westmorland all sit at the same combined $1.10/$1,000 total. On a $300,000 sale, that's $330 in transfer tax anywhere in the county.

How serious is the Salton Sea situation for a buyer near it?

It's a serious, active, worsening crisis — not a resolved historical issue. The Salton Sea has shrunk by more than 60 square miles over the past 30 years as agricultural water transfers have cut inflow, exposing dry lakebed that generates toxic windblown dust.

A 2026 peer-reviewed study tracking 700 local children found measurably impaired lung growth and asthma rates around 24% near the sea — several times the national average (roughly 8.4% for boys, 5.5% for girls). California Air Resources Board modeling ('Dust on the Horizon') projects that mitigation measures won't fully offset increased dust exposure until 2045. If you're evaluating property near the Salton Sea shoreline or in its downwind path, treat current air-quality data and CARB's lakebed-exposure projections as active, ongoing due diligence — not settled history.

What is "Lithium Valley" and does it affect Imperial County real estate?

The Salton Sea Known Geothermal Resource Area sits atop one of the largest lithium deposits in geothermal brine anywhere in the world, and Imperial County is in the middle of a real, fast-moving industrial buildout branded locally as Lithium Valley.

Eleven geothermal power plants already operate on the Salton Sea Geothermal Field, and companies including Berkshire Hathaway Energy's CalEnergy/EnergySource Minerals and Controlled Thermal Resources are developing direct lithium extraction facilities — the Imperial Irrigation District has approved large land sales to these developers, including 3,144 acres to Controlled Thermal Resources for its Hell's Kitchen Geothermal project near Calipatria. This is an active industrial buildout with real implications for local land values, jobs, and infrastructure investment in the county's southern half, worth understanding independent of the Salton Sea's environmental issues.

Is there earthquake risk in Imperial County?

Yes — Imperial County sits on one of California's most seismically active zones. The Imperial Fault ruptured the surface for roughly 40 km (25 miles) or more during the 1940 El Centro earthquake, with displacement reaching about 4.5 meters near the Mexican border.

Alquist-Priolo Earthquake Fault Zones apply along the mapped trace — a property inside a zone requires a specific seller disclosure, and new construction for human occupancy generally can't be sited within 50 feet of the fault trace. Check a specific address, particularly in or near El Centro, against the state's current Alquist-Priolo fault zone maps.

Is farmland here under Williamson Act restrictions like other agricultural counties?

Generally no, and that's a genuine difference from neighboring ag counties — Imperial County filed non-renewal on all of its Williamson Act agricultural-preserve contracts effective January 2011 and has not entered new contracts since, making it one of only a handful of California counties, and the only major agricultural county, outside the program.

If a listing or prior title report references a Williamson Act contract on Imperial County land, confirm its current wind-down status directly rather than assuming an active, ongoing restriction the way you would in Kern, Madera, or Kings County.

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Frequently asked

Is the Salton Sea problem resolved, or is it still getting worse?

It's still getting worse. The lake has shrunk by more than 60 square miles over the past 30 years, and CARB projects mitigation won't fully offset dust exposure until 2045. Treat it as active, ongoing due diligence for any nearby property, not settled history.

What is the transfer tax in Imperial County?

The standard statewide base rate of $1.10 per $1,000 applies flat across the entire county — no city, including chartered El Centro, adds a surcharge.

What is Lithium Valley?

A real, active industrial buildout around the Salton Sea's southern shore extracting lithium from geothermal brine — companies including CalEnergy and Controlled Thermal Resources are already building facilities, with real implications for local land values and jobs in that part of the county.

Can I assume farmland here is under a Williamson Act restriction, like in Kern or Madera County?

No — Imperial County stopped renewing Williamson Act contracts in 2011 and hasn't entered new ones since. Confirm the current status of any referenced contract rather than assuming an active restriction.

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This is educational guidance, not legal advice. Consult a California real estate attorney for legal questions specific to your transaction.