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Walnut Hill Utility Co

Water Supply, Glen Mills, Pennsylvania. NPDES permit PA0050237, in force until Jun 30, 2030. Last 12 months: over a limit 4 times (last June 2026), 18 required values missing. Source: EPA ECHO, Oct 22, 2026.

Reports due
About 28 days after each period: form A monthly (18 values), form Q quarterly (2 values)
Last report on file
June 2026
Oct 2024 – Sep 2025
0 values over a limit, 0 required values missing, 1 of 16 reports late

Last 12 months (Oct 1, 2025 – Sep 30, 2026)

Period endingParameterReportedLimitOver by
December 2025pH, instantaneous minimum5.93 SU≥ 6 SU—
April 2026Nitrogen, ammonia total [as N], monthly average10.51 mg/L≤ 10 mg/L5%
June 2026Nitrogen, ammonia total [as N], monthly average6.92 mg/L≤ 5 mg/L38%
June 2026Phosphorus, total [as P], monthly average1.33 mg/L≤ 1 mg/L33%

Limits in force (28)

ParameterStatisticLimitMonths
Oxygen, dissolved [DO]instantaneous minimum≥ 4 mg/Lall year
pHinstantaneous minimum≥ 6 SUall year
pHinstantaneous maximum≤ 9 SUall year
Solids, total suspendedmonthly average≤ 30 mg/Lall year
Solids, total suspendedmonthly average≤ 37.5 lb/dall year
Nitrogen, total [as N]monthly averagereport only (mg/L)all year
Nitrogen, ammonia total [as N]monthly average≤ 5 mg/LMay–Oct
Nitrogen, ammonia total [as N]monthly average≤ 10 mg/LJan, Feb, Mar, Apr, Nov, Dec
Nitrogen, ammonia total [as N]monthly average≤ 6.3 lb/dMay–Oct
Nitrogen, ammonia total [as N]monthly average≤ 12.5 lb/dJan, Feb, Mar, Apr, Nov, Dec
Phosphorus, total [as P]monthly average≤ 1 mg/LMay–Oct
Phosphorus, total [as P]monthly average≤ 2 mg/LJan, Feb, Mar, Apr, Nov, Dec
Phosphorus, total [as P]monthly average≤ 1.25 lb/dMay–Oct
Phosphorus, total [as P]monthly average≤ 2.5 lb/dJan, Feb, Mar, Apr, Nov, Dec
Flow, in conduit or thru treatment plantmonthly averagereport only (MGD)all year
Flow, in conduit or thru treatment plantdaily maximumreport only (MGD)all year
Chlorine, total residualmonthly average≤ .5 mg/Lall year
Chlorine, total residualinstantaneous maximum≤ 1.2 mg/Lall year
E. coliinstantaneous maximumreport only (#/100mL)all year
Solids, total dissolveddaily maximumreport only (mg/L)all year
Coliform, fecal generalgeometric mean≤ 200 #/100mLMay–Sep
Coliform, fecal generalgeometric mean≤ 200 #/100mLJan, Feb, Mar, Apr, Oct, Nov, Dec
Coliform, fecal generalinstantaneous maximum≤ 1000 #/100mLMay–Sep
Coliform, fecal generalinstantaneous maximum≤ 1000 #/100mLJan, Feb, Mar, Apr, Oct, Nov, Dec
BOD, carbonaceous [5 day, 20 C]monthly average≤ 15 mg/LMay–Oct
BOD, carbonaceous [5 day, 20 C]monthly average≤ 25 mg/LJan, Feb, Mar, Apr, Nov, Dec
BOD, carbonaceous [5 day, 20 C]monthly average≤ 18.8 lb/dMay–Oct
BOD, carbonaceous [5 day, 20 C]monthly average≤ 31.3 lb/dJan, Feb, Mar, Apr, Nov, Dec

How strict are these limits?

Cited limits by parameter: Pennsylvania's rules and the federal ones.

Same industry: the 214 Water Supply permits in Pennsylvania.

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On EPA ECHO: Facility report · DMR history

Your permit document is the final word. As JSON: /api/v1/permits/PA0050237 · MCP: https://passage-data.com/mcp