Clean Water Act discharge permit · NPDES TX0065641

MITCHELL LAKE WWTF, San Antonio, TX: NPDES TX0065641 discharge permit, effluent exceedances, inspections, penalties

Administratively continuedPermit status
MinorDischarger class
6Pollutants under a numeric limit
5Pollutants with an effluent exceedance

MITCHELL LAKE WWTF, held by SAN ANTONIO WATER SYSTEM, holds NPDES permit TX0065641, which discharges to Cottonmouth Creek; Medina River. EPA’s file records it issued September 15, 2010 and expiring March 1, 2015. The status and dates are as EPA’s permit file stood when Velarion loaded it (October 14, 2026); EPA’s free Detailed Facility Report on ECHO carries the permit’s current standing.

Identity

Facility as filed	MITCHELL LAKE WWTF
Permittee as filed	SAN ANTONIO WATER SYSTEM
NPDES ID	TX0065641
Permit status	Administratively continued (past its expiration date and still in force until reissued)
Permit type	Individual permit
Discharger class	Minor discharger
Facility type	Publicly owned treatment works
Program	Publicly owned treatment works
Issued	September 15, 2010
Expiration date	March 1, 2015
Address	San Antonio, TX 78212
Receiving water	COTTONMOUTH CREEK; MEDINA RIVER
Subwatershed	Palo Blanco Creek-Medina River (HUC 121003020509)
SIC	4952 – Sewerage Systems

Cited to the EPA ICIS-NPDES permit file (ECHO download) and EPA’s NAICS/SIC and component files, the same download.

Effluent limits and exceedances

6Pollutants on file
6Under a numeric limit
6With a violation of any kind
5With an effluent exceedance

An effluent exceedance is a discharge monitoring report value over the permit’s numeric limit (EPA’s violation code E90). A violation of any kind also counts a report not filed. Each row is EPA’s own count for that pollutant.

Pollutant or measure	Limits	Violations, any kind	Effluent exceedances	Latest exceedance	Largest exceedance, as filed
pH	2	62	56	November 30, 2018
Solids, total suspended	1	31	27	July 31, 2019	150% over the limit
Oxygen, dissolved [DO]	1	25	22	June 30, 2016	95% over the limit
BOD, 5-day, 20 deg. C	2	13	5	February 28, 2019	19% over the limit
E. coli	2	6	2	July 31, 2014	433% over the limit
Flow, in conduit or thru treatment plant	2	8	0

Cited to the EPA ICIS-NPDES limits and effluent violations files (ECHO download); up to 60 rows shown, most exceedances first.

Inspections, violations and enforcement

1Single-event violations

Date	What EPA recorded	Agency
February 22, 2019	Permit Violations - Violation Specified in Comment	ST6

Velarion’s copy of EPA’s ICIS-NPDES files does not include the inspections, formal enforcement actions and informal enforcement actions files, so this page shows none of them. EPA’s free Detailed Facility Report on ECHO lists this permit’s inspections, enforcement actions and penalties.

Cited to the EPA ICIS-NPDES violation, inspection and enforcement files (ECHO download); up to 50 rows of each shown, newest first.

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EPA publishes a free Detailed Facility Report for every permit on ECHO: its compliance status quarter by quarter, its inspections, and its enforcement actions and penalties. EPA also sends free notices of new inspections and enforcement actions through ECHO Notify; enter NPDES ID TX0065641 there.

Nearby on the register

Figures from EPA’s ICIS-NPDES download, loaded October 14, 2026.

This public-records page covers NPDES permit TX0065641 for MITCHELL LAKE WWTF in San Antonio, TX, held by SAN ANTONIO WATER SYSTEM, with the permit status listed as Administratively continued and a Minor Discharger class. The facts list 6 pollutants under a numeric limit and 5 pollutants with an effluent exceedance, with the subwatershed given as HUC 121003020509.