Henderson’s Industrial Legacy
Henderson, Nevada — now a fast-growing suburb of Las Vegas with over 300,000 residents — was built on wartime industry. The Basic Magnesium Incorporated (BMI) Industrial Complex was established during World War II to produce magnesium for incendiary bombs. After the war, the site transitioned to chemical manufacturing, producing chlorine, perchlorate compounds, and other industrial chemicals.
For decades, the BMI complex was one of the largest producers of ammonium perchlorate in the United States. Ammonium perchlorate is the primary oxidizer in solid rocket fuel — used in the Space Shuttle boosters, military missiles, and other aerospace applications. Manufacturing it generated enormous quantities of perchlorate-contaminated waste.
The result: one of the most significant perchlorate contamination plumes in the country, stretching from the BMI complex into Las Vegas Wash, Lake Mead, and the groundwater beneath Henderson.
Perchlorate: What It Is and Why It Matters
Perchlorate interferes with the thyroid gland’s ability to absorb iodine, which is essential for producing hormones that regulate metabolism, growth, and development. At high enough levels, perchlorate exposure can cause hypothyroidism — particularly dangerous for pregnant women, infants, and young children whose brain development depends on adequate thyroid function.
The EPA set a health reference level for perchlorate in drinking water but has had a long and contentious regulatory history with this contaminant. The agency decided in 2020 not to regulate perchlorate under the Safe Drinking Water Act, reversed course, and the issue has continued to evolve. Nevada set its own perchlorate standard of 18 µg/L for drinking water.
The Contamination Plume
Perchlorate contamination from the BMI complex entered Las Vegas Wash — the drainage channel that carries urban runoff and treated wastewater into Lake Mead. Lake Mead supplies drinking water to Las Vegas, Henderson, and communities across Southern Nevada and into Arizona and California.
At the peak of contamination in the late 1990s, perchlorate levels in Las Vegas Wash exceeded 1,000 µg/L — orders of magnitude above any health-based guideline. The contamination was detected in Lake Mead and in the drinking water intakes for the Southern Nevada Water Authority (SNWA).
A massive remediation effort has been underway since the late 1990s:
- Kerr-McGee (now Tronox/Anadarko) and other responsible parties funded groundwater treatment systems
- Fluidized bed reactor technology was installed to biologically reduce perchlorate in captured groundwater
- Las Vegas Wash monitoring showed significant reduction in perchlorate levels reaching Lake Mead
By the mid-2000s, perchlorate levels at SNWA’s Lake Mead intake points had dropped to low single-digit µg/L levels. Remediation continues, but the acute crisis has been managed.
Beyond Perchlorate
The BMI complex wasn’t just about perchlorate. Other contaminants associated with the site include:
- Hexavalent chromium (chromium-6) — used in manufacturing processes at BMI facilities
- Chlorinated solvents — TCE, PCE, and other volatile organic compounds in soil and groundwater
- Heavy metals — various metals associated with decades of industrial operations
- Manganese — elevated levels in some local groundwater
The BMI complex area has multiple ongoing remediation projects overseen by the Nevada Division of Environmental Protection (NDEP). Several individual parcels within the complex have been addressed through RCRA corrective action programs.
Current Drinking Water Quality
Henderson residents who are served by the city’s water utility receive water primarily from the SNWA system — treated Lake Mead water supplemented by groundwater wells. The treated water meets all federal and state drinking water standards, including Nevada’s perchlorate standard.
SNWA operates one of the most advanced water treatment systems in the country and conducts extensive monitoring for perchlorate and other contaminants. The remediation of BMI-related contamination has reduced perchlorate levels at intake points to well below regulatory thresholds.
But Henderson’s water quality story isn’t over:
- Lake Mead’s declining levels — as the lake drops, contaminant concentrations can increase in the remaining water volume
- PFAS — like most metro areas, Southern Nevada is beginning to assess PFAS levels in drinking water sources
- Naturally occurring contaminants — the desert Southwest has naturally elevated levels of arsenic, uranium, and other minerals in groundwater
What Henderson Residents Can Do
If you’re on city water, Henderson’s water supply through SNWA meets regulatory standards. The annual Consumer Confidence Report details testing results for your specific system.
If you’re on a private well in the Henderson area — particularly anywhere near the BMI complex — testing is critical. Perchlorate, hexavalent chromium, and VOCs should all be on your test list.
For anyone wanting additional peace of mind, a certified water treatment professional can test your water and recommend appropriate systems. Reverse osmosis is effective at removing perchlorate, while activated carbon targets VOCs and some metals.
Sources: Nevada Division of Environmental Protection BMI Complex records; Southern Nevada Water Authority water quality reports; EPA perchlorate regulatory history; USGS Lake Mead water quality studies; Henderson Utility Services Consumer Confidence Reports.