Latest Testing Results

• Lead & Copper (2024 Triennial): The 2024 triennial testing round showed a 90th percentile lead level of 2.6 ppb (first liter) and 2.2 ppb (fifth liter) — a meaningful improvement over the 3.79 ppb recorded in the previous round. All results are well below the EPA action level of 15 ppb. One site exceeded the action level in fifth-liter sampling. SLCDPU has completed its initial lead service line inventory and is eligible for over $39 million in federal loan funding to assist residents with replacements. Check your line material at slcleadandcopper.com.
• PFAS Detection (UCMR5, 2023–2025): UCMR5 monitoring detected multiple PFAS compounds in a single groundwater well that was not in active service at the time of sampling. Levels included PFOS up to 7.1 ppt, PFHxS up to 18.2 ppt, PFHxA up to 5.7 ppt, and PFPeA up to 6.2 ppt. Over 90% of supply comes from unaffected mountain surface water sources. For background on national PFAS regulation, see our water quality testing guide.
• Regulatory Compliance: Salt Lake City’s 2025 CCR confirms full compliance with all federal and state drinking water standards. However, EWG data (2013–2024 testing period) identifies 16 contaminants exceeding health-based guidelines — none of which breach legal MCLs. Total Coliform was found in only 0.17% of distribution system samples; E. coli was detected in 0.00%.

Protected Watershed Sources

• Wasatch Mountain Sources: Primary source (over 60% of supply) includes Parleys, Big Cottonwood, Little Cottonwood, and City Creek canyons — all protected watersheds with strict recreational and development restrictions. These streams feed three surface water treatment plants that use coagulation, flocculation, sedimentation, filtration, and chlorine disinfection.
• Groundwater Sources: Used as a secondary supply during summer peak demand. Deep wells and natural springs tap Wasatch Front aquifers. Some wells have been affected by PFAS contamination and taken offline. Well water does not require additional treatment beyond the naturally high quality established through subsurface filtration, though it is harder (more minerals) than surface water.
• Partner Water Districts: SLCDPU also receives treated water from the Metropolitan Water District of Salt Lake and Sandy (sourced from the Provo, Duchesne, and Weber Rivers, stored in Jordanelle and Deer Creek Reservoirs) and from Jordan Valley Water Conservancy District, providing supply resilience during peak demand and drought.

Disinfection Byproducts: The Biggest EWG Concern

• Total Trihalomethanes (TTHMs): Averaged 34.7 ppb system-wide (range 16.4–75.6 ppb) — well within the EPA legal limit of 80 ppb, but 231x above EWG’s health guideline of 0.15 ppb. TTHMs include chloroform (16.6 ppb, 41x EWG guideline), bromodichloromethane (5.72 ppb, 95x), and dibromochloromethane (1.93 ppb, 19x).
• Haloacetic Acids (HAA5s): Averaged 34.0 ppb (range 12.3–38.6 ppb) — within the EPA legal limit of 60 ppb but 340x above EWG’s health guideline of 0.1 ppb. HAA9 averaged 34.9 ppb — 582x over EWG’s guideline. Key contributors include dichloroacetic acid (20.1 ppb, 101x EWG) and trichloroacetic acid (12.0 ppb, 120x EWG).
• Why So High? These are byproducts of the chlorine disinfection process reacting with naturally occurring organic matter in the source water. Higher organic content in mountain surface water and seasonal blending with groundwater both influence levels. The EPA legal limits were last updated over 20 years ago, which is why the gap between legal limits and EWG’s science-based health guidelines is so large.

Infrastructure Modernization & 2026 Drought Response

• Lead Service Line Program: SLCDPU secured over $39 million in federal loan funding (in partnership with the State of Utah) to assist residents with replacing private lead service lines. An initial inventory has been completed and is publicly accessible at slc.gov/utilities/servicelinematerialmap/.
• City Creek Treatment Plant: A $36.7 million FEMA grant funds major upgrades to maintain reliable, high-quality drinking water supply for the next 50+ years. This is a key resilience investment given climate-driven snowpack variability.
• Stage 2 Drought Advisory (March 2026): Mayor Erin Mendenhall announced a Stage 2 drought response on March 19, 2026 — the first since October 2022. This is driven by well-below-average snow levels and early spring runoff. Stage 2 means mandatory conservation measures are in effect. Residents should follow guidance at slc.gov/utilities. Track ongoing water supply alerts via our live tracker.
• Water Conservation Plan: A new 2025 Water Conservation Plan is moving through City Council for adoption, following public input via town halls and open houses. The plan targets significant reductions in per-capita water use — critical given the city’s arid climate and growing population.

Customer Protection Initiatives

Salt Lake City provides extensive customer support including free water quality testing (contact lead@slc.gov or call 844-SLC-LEAD for lead testing), conservation rebate programmes for high-efficiency fixtures and smart irrigation, and payment assistance through Project Water Assist in partnership with the Salvation Army. The 2025 Annual Report confirms SLCDPU’s commitment to reinvesting in infrastructure while keeping rates equitable and transparent. For a broader picture of water quality across the Mountain West, see our Utah water quality overview and compare with nearby Las Vegas and Denver. If you’re concerned about what’s in your water, visit our water filter solutions page for NSF-certified filter recommendations tailored to Salt Lake City’s detected contaminants.