Williamson County Schools

NPDES permit TN0067164 · Minor POTW · effective, expires 2031-04-30 · EPA's file as of 2026-09-19

Check this month's numbers before you file
Watch this permit — $79 a month. Every Monday, from EPA's newest files: the next report due and when, whether EPA's file holds your last one, any change to this permit's limits or status, and the renewal date.

EPA's record, 2025-09-01 to 2026-08-31

0values over a limit
0required values missing, on 0 form(s)
0of 2 forms filed late

Last period with anything received: 2026-07-31.

Reporting

Reports are due about 15 days after each monitoring period ends (the most common figure among TN permits in EPA's filings — check your permit).

Limits in force (28)

OutfallParameterStatisticLimitMonths
001Oxygen, dissolved [DO]DAILY MN >= 5 mg/L all year
001pHDAILY MN >= 6 SU all year
001pHDAILY MX <= 9 SU all year
001Solids, total suspendedMO AVG <= 30 mg/L all year
001Solids, total suspendedDAILY MX <= 40 mg/L all year
001Solids, settleableDAILY MX <= 1 mL/L all year
001Nitrogen, total [as N]MO AVG report only all year
001Nitrogen, total [as N]DAILY MX report only all year
001Nitrogen, total [as N]DAILY MX report only all year
001Nitrogen, total [as N]ROLL AVG <= 647 lb/yr all year
001Nitrogen, ammonia total [as N]MO AVG <= 1.69 mg/L Jan, Feb, Mar, Apr, Nov, Dec
001Nitrogen, ammonia total [as N]MO AVG <= .887 mg/L May, Jun, Jul, Aug, Sep, Oct
001Nitrogen, ammonia total [as N]DAILY MX <= 7.5 mg/L Jan, Feb, Mar, Apr, Nov, Dec
001Nitrogen, ammonia total [as N]DAILY MX <= 1.5 mg/L May, Jun, Jul, Aug, Sep, Oct
001Phosphorus, total [as P]MO AVG report only all year
001Phosphorus, total [as P]DAILY MX report only all year
001Phosphorus, total [as P]DAILY MX report only all year
001Phosphorus, total [as P]ROLL AVG <= 66 lb/yr all year
001Flow, in conduit or thru treatment plantMO AVG report only all year
001Flow, in conduit or thru treatment plantDAILY MX report only all year
001Chlorine, total residualDAILY MX <= .02 mg/L all year
001Chlorine, total residualMO AVG <= .011 mg/L (alert) all year
001E. coliMO AVG <= 126 #/100mL all year
001E. coliDAILY MX <= 410 #/100mL all year
001BOD, carbonaceous [5 day, 20 C]MO AVG <= 10 mg/L May, Jun, Jul, Aug, Sep, Oct
001BOD, carbonaceous [5 day, 20 C]MO AVG <= 25 mg/L Jan, Feb, Mar, Apr, Nov, Dec
001BOD, carbonaceous [5 day, 20 C]DAILY MX <= 15 mg/L May, Jun, Jul, Aug, Sep, Oct
001BOD, carbonaceous [5 day, 20 C]DAILY MX <= 35 mg/L Jan, Feb, Mar, Apr, Nov, Dec

Built from EPA's ECHO bulk files. EPA's file, not the permit document, is the source: read your permit. Check a report before you file it · All states