Latest Testing Results

• Comprehensive Testing Program: Gilbert Water Quality staff performs up to 100 tests daily on drinking water to ensure compliance with all federal and state health and safety standards set by the EPA and Arizona Department of Environmental Quality.
• Lead and Copper Compliance: Recent testing shows Gilbert maintains full compliance with EPA Lead and Copper Rule regulations, with 90th percentile lead concentrations at 1.33 ppb, well below the 15 ppb action level.
• State Certification: Gilbert operates a state-certified laboratory that analyzes daily process, distribution, and regulatory compliance samples, with additional testing conducted through commercial state-certified laboratories.

Water Sources

• Salt River Project (SRP): Provides 33% of Gilbert’s water supply from the Salt and Verde Rivers, sourced from protected forestland watersheds in northern and eastern Arizona spanning 8.3 million acres.
• Central Arizona Project (CAP): Delivers 29% of water supply via the 336-mile canal system carrying Colorado River water from Lake Havasu through Phoenix to southern Arizona.
• Groundwater Wells: Operates 20 groundwater wells throughout the service area providing 23% of supply, with total groundwater production capacity of nearly 44 million gallons per day including reservoir storage.
• Reclaimed Water: High-quality treated wastewater (A+ rating from ADEQ) comprises 15% of supply, used for irrigation and groundwater recharge, producing approximately 14 million gallons per day.

Advanced Treatment Technology

• North Water Treatment Plant: Treating SRP water with capacity of 45 million gallons per day, currently undergoing complete reconstruction and expansion to 60 million gallons per day, scheduled for completion in December 2027.
• Santan Vista Water Treatment Plant: Co-owned with Chandler, treating CAP water using ballasted flocculation technology with 24 MGD initial capacity (12 MGD for Gilbert), featuring 20-25 minute average process time and 6 MGD onsite reservoir capacity.
• Multi-Barrier Treatment: Both facilities employ comprehensive treatment processes including coagulation, flocculation, sedimentation, filtration, and chlorine disinfection to ensure water safety and quality.

Infrastructure Modernization

• North Plant Reconstruction: Major $100+ million project adding Granular Activated Carbon (GAC) contactors for enhanced contaminant removal, including PFAS treatment capabilities, with completion expected by 2027.
• Underground Water Storage: Comprehensive recharge program at Riparian Preserve and South Area Recharge Facility, storing over 200 billion gallons of water (9 times annual usage) with second-largest storage credits in Phoenix AMA.
• Distribution System: Over 700 miles of pipeline infrastructure delivering water at optimal pressure (60-80 psi) with ongoing investments in system improvements and modernization.

Customer Protection Initiatives

Gilbert Water provides extensive customer support through various programs, including the Utility Billing Assistance Program launched in 2024 to help residents facing financial challenges. The utility publishes annual Consumer Confidence Reports by July 1st each year, providing transparent water quality information to all customers. Gilbert’s commitment to water security includes maintaining Arizona’s 100-year Assured Water Supply designation and implementing comprehensive conservation programs. The community’s investment in advanced treatment technologies, diverse water portfolio, and proactive infrastructure improvements demonstrates dedication to providing safe, reliable drinking water while preparing for challenges including population growth, Colorado River shortages, and emerging contaminants like PFAS.