Clarksville Montgomery County School System — NPDES permit TN0024651: limits, due date and EPA's record

Sewage treatment plant, Woodlawn, Tennessee. NPDES permit TN0024651, in force until Jun 30, 2030. Last 12 months: over a limit 3 times (last May 2026). Source: EPA ECHO, Oct 22, 2026.

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

Period ending	Parameter	Reported	Limit	Over by
December 2025	Nitrogen, ammonia total [as N], monthly average	2.26 mg/L	≤ 2.1 mg/L	8%
January 2026	Nitrogen, ammonia total [as N], daily maximum	3.45 mg/L	≤ 3.2 mg/L	8%
May 2026	Nitrogen, ammonia total [as N], daily maximum	2.19 mg/L	≤ 1.8 mg/L	22%

Limits in force (18)

Parameter	Statistic	Limit	Months
Oxygen, dissolved [DO]	daily minimum	≥ 6 mg/L	all year
pH	daily minimum	≥ 6 SU	all year
pH	daily maximum	≤ 9 SU	all year
Solids, total suspended	monthly average	≤ 30 mg/L	all year
Solids, total suspended	daily maximum	≤ 45 mg/L	all year
Solids, settleable	daily maximum	≤ 1 mL/L	all year
Nitrogen, ammonia total [as N]	monthly average	≤ 1.2 mg/L	May–Oct
Nitrogen, ammonia total [as N]	monthly average	≤ 2.1 mg/L	Jan, Feb, Mar, Apr, Nov, Dec
Nitrogen, ammonia total [as N]	daily maximum	≤ 1.8 mg/L	May–Oct
Nitrogen, ammonia total [as N]	daily maximum	≤ 3.2 mg/L	Jan, Feb, Mar, Apr, Nov, Dec
Flow, in conduit or thru treatment plant	monthly average	report only (MGD)	all year
Flow, in conduit or thru treatment plant	daily maximum	report only (MGD)	all year
Chlorine, total residual	monthly average	≤ .01 mg/L	all year
Chlorine, total residual	daily maximum	≤ .02 mg/L	all year
E. coli	monthly average	≤ 126 #/100mL	all year
E. coli	daily maximum	≤ 410 #/100mL	all year
BOD, carbonaceous [5 day, 20 C]	monthly average	≤ 25 mg/L	all year
BOD, carbonaceous [5 day, 20 C]	daily maximum	≤ 35 mg/L	all year

How strict are these limits?

Your permit document is the final word. As JSON: /api/v1/permits/TN0024651 · MCP: https://passage-data.com/mcp