Mansfield City

• Despite the reservoir's prominence, only about 22% of Mansfield's tap water is lake water - roughly 78% comes from municipal wells, and the blend shifts with algae blooms and taste-and-odor episodes.
• Potassium permanganate is dosed right at the reservoir intake for one specific job: keeping zebra mussels from colonizing the intake line.
• About 5.5 million cubic yards of silt have settled into Clear Fork Reservoir since 1949 - roughly a quarter of its capacity - and it has never once been dredged.
• Mansfield voters rejected a quarter-percent water-main income tax in November 2023, then passed the very same tax four months later by 97 votes.

• 1949Clear Fork Reservoir built, impounding the Clear Fork of the Mohican River to serve Mansfield as its surface water source.
• 1960Present wastewater treatment plant went into service as a 4 MGD facility; capacity was expanded between 1984 and 1987.
• 2023-2024Voters rejected a quarter-percent water-main income tax in Nov. 2023 (5,865-5,251), then approved it in March 2024 by 97 votes (2,701-2,604).
• 2025City launched a $3.6 million water main program and recorded three treatment technique violations at the water plant, including a nine-hour turbidity violation on Jan. 2.
• 2026Stantec sediment survey found roughly 5.5 million cubic yards of silt and ~26% capacity loss, but concluded the reservoir remains dependable for at least 50 more years.

How it is treated

Blend of surface and ground water - about 22% from the 4.4-billion-gallon Clear Fork Reservoir (24-inch line) and about 78% from municipal wells (two 18-inch lines), with the ratio set by lake clarity, algal blooms and taste/odor. Potassium permanganate at the intake controls zebra mussels; then…

Water pressure

not published; no system-wide psi figure appears in the city's plant pages or the 2025 CCR

No per-1,000-gallon figure is published online. Utility Collections directs residents to city ordinances 937.11 (water) and 941.08 (sewer) for yearly rates and fees; the ordinance…

EPA compliance record

Lead at the tap: 90th-percentile result 2 ppb in 2025 (action level 15 ppb).

EPA health-based violations since 2015:

• 2025Total coliform · treatment technique violation · returned to compliance
• 2025Surface Water Treatment Rule · treatment technique violation · returned to compliance
• 2024Lead and Copper Rule (lead) · treatment technique violation · returned to compliance
• 2023Lead and Copper Rule · treatment technique violation · returned to compliance
• 2019Total coliform · treatment technique violation · returned to compliance
• 2018Lead and Copper Rule · treatment technique violation · returned to compliance

EPA's count of 7 includes 1 repeat quarterly violation of the problems listed.

8 violations of any kind logged since 2020, 3 of them paperwork (monitoring, reporting, public notice or consumer report).

Recent and current work

• Water main replacement program (4-inch to 8-inch mains) · $3.6 million · 2025 · under construction
  About 14,000 feet of main, 37 hydrants and 246 reconnected homes in six areas; first phase of a 53-mile replacement need.
• Clear Fork Reservoir sediment survey · $149,799 · 2026 · completed
  Stantec study found ~5.5 million cubic yards of sediment and ~26% capacity loss, yet a dependable supply for 50+ years.

Planned or needed

• Continued small-diameter water main replacement (53 miles total) · 2025-2029 · planned
  About three miles per year over roughly four funding cycles, paid from the 0.25% income tax generating ~$4.8 million annually.

Silt has claimed roughly 26% of Clear Fork Reservoir's capacity since 1949 and it has never been dredged, though a 2026 Stantec survey found 50+ years of dependable supply. Nearer-term pressures are on the treatment side: three treatment technique violations in 2025 and disinfection byproducts running close to their limits.

Sanitary

City-operated wastewater treatment plant (not a regional district): 12 MGD average design flow, 25 MGD peak. Treatment runs equalization, bar screening, aerated grit removal, primary clarification, extended aeration in eight tanks, four final clarifiers, then chlorination and dechlorination, with anaerobic digestion and centrifuge…

Storm

Largely separate storm system - about 400 miles of storm lines, 7,200-plus catch basins and roughly 1,200 outfalls draining to 10 major waterways. No stormwater utility fee is published.

Compiled from the utility's own reports and public records, then independently re-checked against primary sources.