The largest water utilities in the US.

Largest water utilities

Every US community water system serving at least 200,000 people, ranked by the population served that each system reports to EPA (EPA). Search by utility, city or state.

About these numbers

• Figures come from EPA's national community water system service area dataset, which uses population and connection counts that systems report to the Safe Drinking Water Information System (EPA).
• Population served is retail: wholesale suppliers that sell water to other utilities, such as the Metropolitan Water District of Southern California, aren't ranked by the people their customers serve.
• Some large utilities run several separate systems, and each is listed under its own EPA ID.
• Counts are estimates that systems update on their own schedules, so some are older than others.

Selling to water utilities

Water utilities buy treatment chemicals and equipment, pipe and valves, meters and AMI, SCADA and cybersecurity, lead service line inventory and replacement, asset management and billing software, and engineering and construction.

• Read the capital improvement plan. Big utilities publish multi-year CIPs and rate filings that show what they will buy.
• Follow the funding. State Revolving Funds, WIFIA loans and lead pipe replacement money pay for much of the work.
• Know who decides. Engineering, operations, IT and procurement each have a say, and boards or councils approve large contracts.
• Bring peer references. Utilities lean heavily on what similar systems use.

See how utilities buy, selling water technology and our utilities market page.

Sources

• EPA, Community Water System Service Area Boundaries
• EPA Water System Boundaries feature service (population and connection counts)

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