Lagoon systems: wastewater treatment plants in Utah
11 plants · 42% of the state · no reported flow
Klarifi identifies 11 publicly owned wastewater treatment plants with lagoon systems in Utah, 42% of the 26 plants in the state (no reported flow). The largest is Morgan City Corporation in Morgan at 0.32 MGD.
Lagoon systems treat wastewater in large earthen ponds over weeks of retention time, with or without mechanical aeration. They serve thousands of small towns because they are cheap to run, but they struggle with ammonia and nutrient limits, fill with sludge over decades and are the plants most often converted or upgraded when a permit is renewed.
The largest lagoons in Utah
| # | Facility | City | Avg flow (MGD) | NPDES permit | Expires | Violations (3y) |
|---|---|---|---|---|---|---|
| 1 | Morgan City Corporation | Morgan | 0.32 | UT0020893 | Aug 2030 | 3 |
| 2 | Brigham City Corporation Waste Water | Brigham City | — | UT0022365 | Apr 2030 | 1 |
| 3 | Duchesne City WWTP | Duchesne | — | UT0020095 | Oct 2029 | 0 |
| 4 | Eureka | Eureka | — | UT0024601 | Jan 2025 | 179 |
| 5 | Grantsville City | Grantsville | — | UT0021130 | Mar 2029 | 12 |
| 6 | Henefer | Henefer | — | UT0020192 | Jan 2030 | 12 |
| 7 | Lewiston City | Lewiston | — | UT0020214 | Jul 2028 | 5 |
| 8 | Little Mountain Service Area | Ogden | — | UT0025569 | Nov 2029 | 0 |
| 9 | Manti City Lagoons | Manti | — | UT0026026 | Jan 2022 | 0 |
| 10 | South Davis Sewer Improvement District South Plant | North Salt Lake | — | UT0021628 | Dec 2026 | 1 |
| 11 | Stansbury Park Wastewater | Stansbury Park | — | UT0025241 | Apr 2028 | 33 |
Contacts and project signals for every plant on this list
Klarifi adds verified decision-maker contacts, permit limits, discharge monitoring data and the capital projects planned in each city, filterable by technology, size and compliance record.
Other technologies in Utah
Lagoon systems in other states
Lagoon systems in Utah: questions
Sources and methodology
Flow, permit and violation figures come from the EPA's ICIS-NPDES discharge monitoring records. Population served comes from the Clean Watersheds Needs Survey 2022. Treatment structures are identified by Klarifi's review of aerial imagery, and capital improvement projects are extracted from published municipal budget documents. Violations are counted over the last three years of monitoring reports.
Data refreshed September 11, 2026.