Is Las Vegas, NV Tap Water Safe to Drink?

Where Does Las Vegas Get Its Water?

Las Vegas draws its drinking water from a combination of surface water and groundwater sources in the Mojave Desert region. Two utilities serve the city: the Las Vegas Valley Water District and North Las Vegas Utilities. Together they supply water across 20 ZIP codes in Clark County.

The system includes multiple treatment and distribution facilities. Recognizable sites in the network include the Carlton Square and Fayle Reservoir advanced membrane surface water treatment plants, the Warm Springs reverse osmosis facility, the Luce North and Luce South facilities, Silver Mesa, Sun Valley, and several individual well treatment plants throughout the valley.

A number of groundwater wells also feed portions of the system. These wells go through their own on-site treatment before water enters the distribution network, giving the overall supply a mixed character of treated surface water and treated groundwater blended across the service area.

How Is Las Vegas Tap Water Treated?

Water in Las Vegas goes through several treatment steps before it reaches your tap. The process includes coagulation to clump particles together, filtration to remove them, and adsorption-based treatment to reduce organic compounds and some contaminants. Some facilities also use groundwater disinfection and corrosion control steps.

Disinfection uses a combination of methods across the system, including free chlorine, chlorine gas, chloramines, ozone, and ultraviolet light. These disinfectants kill bacteria and viruses and keep water safe through the pipes to your home. A small residual disinfectant level is maintained in the distribution system, which can produce a mild chlorine taste or odor at the tap.

The Warm Springs facility uses reverse osmosis membrane filtration, a more intensive process that strips dissolved minerals and some contaminants from groundwater before it enters the supply. The advanced membrane surface water treatment plants at Carlton Square and Fayle Reservoir apply similar high-level filtration to surface water inputs.

What's in Las Vegas Tap Water?

The main concern in Las Vegas tap water is lithium. Recent EPA sampling found lithium at levels up to 52.9 micrograms per liter (µg/L). EPA has a non-regulatory health reference level of 10 µg/L for lithium in drinking water. All 20 ZIP codes in this dataset showed detections above that benchmark. There is currently no enforceable federal maximum contaminant level for lithium in drinking water.

Several PFAS compounds were also detected across the system. PFTrDA, HFPO-DA, 11Cl-PF3OUdS, and PFBA each showed up in samples, with measured values at or at the reporting limit of 0.005 to 0.007 µg/L. None of these specific compounds had detections reported above an applicable guideline in this dataset, but their presence is worth knowing about, particularly for households with infants or people who are pregnant.

Lithium occurs naturally in some groundwater and surface water sources in the western United States, and the Las Vegas Valley's geology contributes to elevated background levels. PFAS compounds can enter water supplies from a range of industrial and consumer sources and are monitored nationally under EPA's expanded testing program.

Health Risk Profile for Las Vegas

Lithium is the primary concern here. EPA's health reference level for lithium is 10 µg/L, a non-regulatory screening benchmark, not an enforceable legal limit. The peak detected level in Las Vegas was 52.9 µg/L, more than five times that benchmark. Because there is no federal maximum contaminant level for lithium, this is not a compliance violation, but it is a signal that the level is higher than what EPA considers a low-risk target.

Infants, pregnant individuals, and people who are breastfeeding face the greatest potential concern from elevated lithium, as developing brains and nervous systems are more sensitive to this mineral. People managing certain health conditions, including thyroid or kidney issues, may also want to consult their doctor about their tap water exposure.

For this contaminant profile, a filter certified to NSF/ANSI 58 (the independent third-party standard for reverse osmosis systems, issued by NSF International) is the most effective choice for reducing lithium and PFAS compounds at the tap. For PFAS specifically, also look for NSF/ANSI P473 certification on the product label. Pitcher filters and faucet-mount filters with NSF/ANSI 53 certification can help with some contaminants but may not reduce lithium or PFAS as reliably as reverse osmosis.

The science on lithium in drinking water is still developing, and EPA has not finalized a regulatory limit. The PFAS detections here are at very low levels, at or near the minimum the equipment can reliably measure. That said, given the lithium levels, households with young children or people who are pregnant have a reasonable basis to use a certified filter as a precaution.