Harris County Ud 16 — NPDES permit TX0091481: limits, due date and EPA's record

Sewage treatment plant, Houston, Texas. NPDES permit TX0091481, in force until Mar 3, 2028. Last 12 months: over a limit once (last April 2026). Source: EPA ECHO, Oct 22, 2026.

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

Period ending	Parameter	Reported	Limit	Over by
April 2026	Flow, in conduit or thru treatment plant, daily average	.506 MGD	≤ .5 MGD	1%

Limits in force (18)

Parameter	Statistic	Limit	Months
Oxygen, dissolved [DO]	monthly minimum	≥ 4 mg/L	all year
pH	minimum	≥ 6 SU	all year
pH	maximum	≤ 9 SU	all year
Solids, total suspended	daily average	≤ 15 mg/L	all year
Solids, total suspended	daily maximum	≤ 40 mg/L	all year
Solids, total suspended	daily average	≤ 63 lb/d	all year
Nitrogen, ammonia total [as N]	daily average	≤ 3 mg/L	all year
Nitrogen, ammonia total [as N]	daily maximum	≤ 10 mg/L	all year
Nitrogen, ammonia total [as N]	daily average	≤ 13 lb/d	all year
Flow, in conduit or thru treatment plant	daily average	≤ .5 MGD	all year
Flow, in conduit or thru treatment plant	daily maximum	report only (MGD)	all year
Chlorine, total residual	monthly minimum	≥ 1 mg/L	all year
Chlorine, total residual	monthly maximum	≤ 4 mg/L	all year
E. coli	daily average	≤ 63 CFU/100mL	all year
E. coli	daily maximum	≤ 200 CFU/100mL	all year
BOD, carbonaceous [5 day, 20 C]	daily average	≤ 10 mg/L	all year
BOD, carbonaceous [5 day, 20 C]	daily maximum	≤ 25 mg/L	all year
BOD, carbonaceous [5 day, 20 C]	daily average	≤ 42 lb/d	all year

How strict are these limits?

Your permit document is the final word. As JSON: /api/v1/permits/TX0091481 · MCP: https://passage-data.com/mcp