Clean Water Act discharge permit · NPDES TX0081337
NW HARRIS COUNTY MUD 20 WWTP, Houston, TX: NPDES TX0081337 discharge permit, effluent exceedances, inspections, penalties
- Administratively continuedPermit status
- MajorDischarger class
- 55Pollutants under a numeric limit
- 6Pollutants with an effluent exceedance
- 1Inspections on file
- 0Formal enforcement actions
NW HARRIS COUNTY MUD 20 WWTP, held by NORTHWEST HARRISCOUNTY MUD 20, holds NPDES permit TX0081337, which discharges to Cypress Creek. EPA’s file records it issued March 26, 2018 and expiring February 1, 2023.
NW HARRIS COUNTY MUD 20 WWTP, Houston, Texas: Individual permit TX0081337, held by NORTHWEST HARRISCOUNTY MUD 20; Publicly owned treatment works; Administratively continued (past its expiration date and still in force until reissued); issued March 26, 2018, term to February 1, 2023; discharges to CYPRESS CREEK.
- Nitrogen, ammonia total [as N]: 6 limits, 25 violations of any kind, 16 effluent exceedances, latest October 31, 2023, largest 233% over the limit.
- Solids, total suspended: 3 limits, 15 violations of any kind, 3 effluent exceedances, latest September 30, 2008, largest 17% over the limit.
- BOD, carbonaceous [5 day, 20 C]: 6 limits, 13 violations of any kind, 1 effluent exceedance, latest June 30, 2007, largest 24% over the limit.
- Chlorine, total residual: 2 limits, 8 violations of any kind, 1 effluent exceedance, latest November 30, 2023, largest 0% over the limit.
- Oxygen, dissolved [DO]: 2 limits, 4 violations of any kind, 1 effluent exceedance, latest September 30, 2008, largest 5% over the limit.
- E. coli, colony forming units [CFU]: 2 limits, 1 violation of any kind, 1 effluent exceedance, latest October 31, 2023, largest 1,110% over the limit.
- Flow, in conduit or thru treatment plant: 4 limits, 14 violations of any kind, 0 effluent exceedances.
- NOEC Sub-Lethal Static Renewal 7 Day Chronic Ceriodaphnia dubia: 2 limits, 12 violations of any kind, 0 effluent exceedances.
- Pass/Fail Sub-Lethal Static Renewal 7 Day Chronic Ceriodaphnia dubia: 2 limits, 12 violations of any kind, 0 effluent exceedances.
- Whole effluent toxicity - retest #1: 3 limits, 10 violations of any kind, 0 effluent exceedances.
- Low Flow Pass/Fail Survival Test Static Renewal 7 Day Chronic Ceriodaphnia dubia: 2 limits, 10 violations of any kind, 0 effluent exceedances.
- Low Flow Pass/Fail Survival Test Static Renewal 7 Day Chronic Pimephales promelas: 2 limits, 10 violations of any kind, 0 effluent exceedances.
- NOEC Lethal Static Renewal 7 Day Chronic Ceriodaphnia dubia: 2 limits, 10 violations of any kind, 0 effluent exceedances.
- NOEC Lethal Static Renewal 7 Day Chronic Pimephales promelas: 2 limits, 10 violations of any kind, 0 effluent exceedances.
- NOEC Sub-Lethal Static Renewal 7 Day Chronic Pimephales promelas: 2 limits, 10 violations of any kind, 0 effluent exceedances.
- Pass/Fail Sub-Lethal Static Renewal 7 Day Chronic Pinephales promelas: 2 limits, 10 violations of any kind, 0 effluent exceedances.
- Whole effluent toxicity - retest #2: 3 limits, 8 violations of any kind, 0 effluent exceedances.
- pH: 3 limits, 6 violations of any kind, 0 effluent exceedances.
- LOEC Sub-Lethal Reproduction Static Renewal 7 Day Chronic Ceriodaphnia dubia: 2 limits, 6 violations of any kind, 0 effluent exceedances.
- LOEC Lethal Survival Static Renewal 7 Day Chronic Ceriodaphnia dubia: 2 limits, 4 violations of any kind, 0 effluent exceedances.
- LOEC Lethal Survival Static Renewal 7 Day Chronic Pimephales promelas: 2 limits, 4 violations of any kind, 0 effluent exceedances.
- LOEC Sub-Lethal Reproduction Static Renewal 7 Day Chronic Pimephales promelas: 2 limits, 4 violations of any kind, 0 effluent exceedances.
- Compliance w/part 258 sludge requirement: 1 limit, 1 violation of any kind, 0 effluent exceedances.
- Arsenic, dry weight: 5 limits, 0 violations of any kind, 0 effluent exceedances.
- Chromium, sludge, total, dry weight [as Cr]: 5 limits, 0 violations of any kind, 0 effluent exceedances.
- Selenium, dry weight: 3 limits, 0 violations of any kind, 0 effluent exceedances.
- Copper, dry weight: 3 limits, 0 violations of any kind, 0 effluent exceedances.
- Cadmium, dry weight: 3 limits, 0 violations of any kind, 0 effluent exceedances.
- Molybdenum, sludge, total, dry weight [as Mo]: 3 limits, 0 violations of any kind, 0 effluent exceedances.
- Zinc, sludge, total, dry weight [as Zn]: 3 limits, 0 violations of any kind, 0 effluent exceedances.
- Lead, sludge, total, dry weight [as Pb]: 3 limits, 0 violations of any kind, 0 effluent exceedances.
- Nickel, sludge, total, dry weight [as Ni]: 3 limits, 0 violations of any kind, 0 effluent exceedances.
- Mercury, sludge, total, dry weight [as Hg]: 3 limits, 0 violations of any kind, 0 effluent exceedances.
- Nickel, total [as Ni]: 2 limits, 0 violations of any kind, 0 effluent exceedances.
- Whole effluent toxicity: 2 limits, 0 violations of any kind, 0 effluent exceedances.
- Level of pathogen requirements achieved: 2 limits, 0 violations of any kind, 0 effluent exceedances.
- Description of pathogen option used: 2 limits, 0 violations of any kind, 0 effluent exceedances.
- Vector attraction reduction alternative used: 2 limits, 0 violations of any kind, 0 effluent exceedances.
- Fecal coliform: 1 limit, 0 violations of any kind, 0 effluent exceedances.
- Polychlorinated biphenyls [PCBs]: 1 limit, 0 violations of any kind, 0 effluent exceedances.
- Toxicity characteristic leaching procedure: 1 limit, 0 violations of any kind, 0 effluent exceedances.
- Annual whole sludge application rate: 1 limit, 0 violations of any kind, 0 effluent exceedances.
- Ann. amt sludge disposed by other method: 1 limit, 0 violations of any kind, 0 effluent exceedances.
- Annual amt of sludge incinerated: 1 limit, 0 violations of any kind, 0 effluent exceedances.
- Annual sludge production, total: 1 limit, 0 violations of any kind, 0 effluent exceedances.
- Annual amount of sludge land applied: 1 limit, 0 violations of any kind, 0 effluent exceedances.
- Annual amt. sludge disposed surface unit: 1 limit, 0 violations of any kind, 0 effluent exceedances.
- Annual amt sludge disposed in landfill: 1 limit, 0 violations of any kind, 0 effluent exceedances.
- Annual amt sludge transported interstate: 1 limit, 0 violations of any kind, 0 effluent exceedances.
- Unit w/liner/leachate collection system: 1 limit, 0 violations of any kind, 0 effluent exceedances.
- Boundary areas: 1 limit, 0 violations of any kind, 0 effluent exceedances.
- Salmonella: 1 limit, 0 violations of any kind, 0 effluent exceedances.
- Pollutant table from 503.13: 1 limit, 0 violations of any kind, 0 effluent exceedances.
- LC50 Pass/Fail Static 24Hr Acute D. Pulex: 1 limit, 0 violations of any kind, 0 effluent exceedances.
- LC50 Pass/Fail Static 24Hr Acute Pimephales promelas: 1 limit, 0 violations of any kind, 0 effluent exceedances.
- March 31, 2026: Permit Violations - Violation Specified in Comment (ST6).
- March 31, 2026: Evaluation (S).
Texas holds 1,720 Publicly owned treatment works coverages of this permit type in EPA’s file; 726 were issued before TX0081337.
Coverages issued nearest TX0081337
- March 21, 2018: HARRIS COUNTY MUD 360 WWTP, Houston, TX0113107, held by HARRIS COUNTY MUD NO. 360
- March 21, 2018: HARRIS COUNTY MUD 24 WTP 2, Houston, TX0113115, held by HARRIS COUNTY MUD NO. 124
- March 26, 2018: IMPERIAL VALLEY WWTP, Houston, TX0020478, held by CITY OF HOUSTON
- March 26, 2018: PONDEROSA JOINT POWERS AGENCY REGIONAL WWTP, Houston, TX0046761, held by PONDEROSA JOINT POWERS AGENCY
- March 26, 2018: NORTHWEST HARRIS COUNTY MUD 5 WWP 1, Houston, TX0072346, held by NORTHWEST HARRIS COUNTY MUD 5
- March 26, 2018: RICHEY ROAD MUD WWTP, Westfield, TX0092967, held by RICHEY ROAD MUD
- March 26, 2018: HARRIS COUNTY MUD 344 WWTP, Houston, TX0104965, held by HARRIS COUNTY MUD 344
- March 26, 2018: HUNTER'S GLEN MUD WWTP, Houston, TX0118371, held by HUNTER'S GLEN MUD
- March 26, 2018: HARRIS COUNTY MUD 434 WWTP, Harris County, TX0127311, held by HARRIS CO MUD 434
- March 26, 2018: GRANT ROAD PUD WWTP, Cypress, TX0134627, held by GRANT ROAD PUD
NW HARRIS COUNTY MUD 20 WWTP among its neighbors
EPA’s permit file holds 170 discharge permits in the Turkey Creek-Cypress Creek subwatershed (HUC 120401020107), TX0081337 among them. Its county holds 4,455, 195 of them major permits; TX0081337 is a major permit.
Other permits in the Turkey Creek-Cypress Creek subwatershed (HUC 120401020107)
- AMAZONCOM SERVICES SAH1, Houston: TXR05GP18, minor permit, permit term to August 13, 2026
- AMC FACILITIES WWTF, Houston: TX0083836, minor permit, discharging to ONSITE POND;UNNAMED DITCH;HCFCD P140-04-03, permit term to December 1, 2022
- AMERICAN BUILDERS & CONTRACTORS SUPPLY, Houston: TXR05GD66, minor permit, permit term to August 13, 2026
- ARTHUR BAYER PARK WWTP, Houston: TX0096865, minor permit, discharging to LEMM GULLY; CYPRESS CREEK, permit term to February 1, 2018
- BASS PRO SHOPS OUTDOOR WORLD - SPRING, Spring: TXR1572PD, minor permit, discharging to WUNSCHE GULLY, permit term to March 4, 2028
- BAUER HOCKLEY MINI STORAGE, Hockley: TXR1540YX, minor permit, discharging to LAKE HOUSTON, permit term to March 4, 2028
- BRADBURY FOREST SECTION 11-14, Spring: TXR1511NG, minor permit, discharging to SPRING CREEK, permit term to March 4, 2028
- BRIDGESTONE MUD WWTP NO. 1, Houston: TX0072150, major permit, discharging to SEALS GULLY, CYPRESS CREEK, permit term to April 13, 2024
- BRIDGESTONE MUD WWTP NO. 2, Tomball: TX0140643, minor permit, discharging to SPRING CREEK, permit term to March 14, 2027
- BRIDGESTONE WWTP NO 1 IMPROVEMENTS, Spring: TXR1566XA, minor permit, discharging to CYPRESS CREEK, permit term to March 4, 2028
Identity
| Facility as filed | NW HARRIS COUNTY MUD 20 WWTP |
|---|---|
| Permittee as filed | NORTHWEST HARRISCOUNTY MUD 20 |
| NPDES ID | TX0081337 |
| Permit status | Administratively continued (past its expiration date and still in force until reissued) |
| Permit type | Individual permit |
| Discharger class | Major discharger |
| Facility type | Publicly owned treatment works |
| Program | Publicly owned treatment works |
| Issued | March 26, 2018 |
| Expiration date | February 1, 2023 |
| Address | Houston, TX 77068 |
| Receiving water | CYPRESS CREEK |
| Subwatershed | Turkey Creek-Cypress Creek (HUC 120401020107) |
| SIC | 4952 – Sewerage Systems |
Effluent limits and exceedances
- 55Pollutants on file
- 55Under a numeric limit
- 23With a violation of any kind
- 6With 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 |
|---|---|---|---|---|---|
| Nitrogen, ammonia total [as N] | 6 | 25 | 16 | October 31, 2023 | 233% over the limit |
| Solids, total suspended | 3 | 15 | 3 | September 30, 2008 | 17% over the limit |
| BOD, carbonaceous [5 day, 20 C] | 6 | 13 | 1 | June 30, 2007 | 24% over the limit |
| Chlorine, total residual | 2 | 8 | 1 | November 30, 2023 | 0% over the limit |
| Oxygen, dissolved [DO] | 2 | 4 | 1 | September 30, 2008 | 5% over the limit |
| E. coli, colony forming units [CFU] | 2 | 1 | 1 | October 31, 2023 | 1,110% over the limit |
| Flow, in conduit or thru treatment plant | 4 | 14 | 0 | ||
| NOEC Sub-Lethal Static Renewal 7 Day Chronic Ceriodaphnia dubia | 2 | 12 | 0 | ||
| Pass/Fail Sub-Lethal Static Renewal 7 Day Chronic Ceriodaphnia dubia | 2 | 12 | 0 | ||
| Whole effluent toxicity - retest #1 | 3 | 10 | 0 | ||
| Low Flow Pass/Fail Survival Test Static Renewal 7 Day Chronic Ceriodaphnia dubia | 2 | 10 | 0 | ||
| Low Flow Pass/Fail Survival Test Static Renewal 7 Day Chronic Pimephales promelas | 2 | 10 | 0 | ||
| NOEC Lethal Static Renewal 7 Day Chronic Ceriodaphnia dubia | 2 | 10 | 0 | ||
| NOEC Lethal Static Renewal 7 Day Chronic Pimephales promelas | 2 | 10 | 0 | ||
| NOEC Sub-Lethal Static Renewal 7 Day Chronic Pimephales promelas | 2 | 10 | 0 | ||
| Pass/Fail Sub-Lethal Static Renewal 7 Day Chronic Pinephales promelas | 2 | 10 | 0 | ||
| Whole effluent toxicity - retest #2 | 3 | 8 | 0 | ||
| pH | 3 | 6 | 0 | ||
| LOEC Sub-Lethal Reproduction Static Renewal 7 Day Chronic Ceriodaphnia dubia | 2 | 6 | 0 | ||
| LOEC Lethal Survival Static Renewal 7 Day Chronic Ceriodaphnia dubia | 2 | 4 | 0 | ||
| LOEC Lethal Survival Static Renewal 7 Day Chronic Pimephales promelas | 2 | 4 | 0 | ||
| LOEC Sub-Lethal Reproduction Static Renewal 7 Day Chronic Pimephales promelas | 2 | 4 | 0 | ||
| Compliance w/part 258 sludge requirement | 1 | 1 | 0 | ||
| Arsenic, dry weight | 5 | 0 | 0 | ||
| Chromium, sludge, total, dry weight [as Cr] | 5 | 0 | 0 | ||
| Selenium, dry weight | 3 | 0 | 0 | ||
| Copper, dry weight | 3 | 0 | 0 | ||
| Cadmium, dry weight | 3 | 0 | 0 | ||
| Molybdenum, sludge, total, dry weight [as Mo] | 3 | 0 | 0 | ||
| Zinc, sludge, total, dry weight [as Zn] | 3 | 0 | 0 | ||
| Lead, sludge, total, dry weight [as Pb] | 3 | 0 | 0 | ||
| Nickel, sludge, total, dry weight [as Ni] | 3 | 0 | 0 | ||
| Mercury, sludge, total, dry weight [as Hg] | 3 | 0 | 0 | ||
| Nickel, total [as Ni] | 2 | 0 | 0 | ||
| Whole effluent toxicity | 2 | 0 | 0 | ||
| Level of pathogen requirements achieved | 2 | 0 | 0 | ||
| Description of pathogen option used | 2 | 0 | 0 | ||
| Vector attraction reduction alternative used | 2 | 0 | 0 | ||
| Fecal coliform | 1 | 0 | 0 | ||
| Polychlorinated biphenyls [PCBs] | 1 | 0 | 0 | ||
| Toxicity characteristic leaching procedure | 1 | 0 | 0 | ||
| Annual whole sludge application rate | 1 | 0 | 0 | ||
| Ann. amt sludge disposed by other method | 1 | 0 | 0 | ||
| Annual amt of sludge incinerated | 1 | 0 | 0 | ||
| Annual sludge production, total | 1 | 0 | 0 | ||
| Annual amount of sludge land applied | 1 | 0 | 0 | ||
| Annual amt. sludge disposed surface unit | 1 | 0 | 0 | ||
| Annual amt sludge disposed in landfill | 1 | 0 | 0 | ||
| Annual amt sludge transported interstate | 1 | 0 | 0 | ||
| Unit w/liner/leachate collection system | 1 | 0 | 0 | ||
| Boundary areas | 1 | 0 | 0 | ||
| Salmonella | 1 | 0 | 0 | ||
| Pollutant table from 503.13 | 1 | 0 | 0 | ||
| LC50 Pass/Fail Static 24Hr Acute D. Pulex | 1 | 0 | 0 | ||
| LC50 Pass/Fail Static 24Hr Acute Pimephales promelas | 1 | 0 | 0 |
Inspections, violations and enforcement
- 1Single-event violations
| Date | What EPA recorded | Agency |
|---|---|---|
| March 31, 2026 | Permit Violations - Violation Specified in Comment | ST6 |
Inspections
| Date | What EPA recorded | Agency |
|---|---|---|
| March 31, 2026 | Evaluation | S |
Formal enforcement and penalties
0 formal actions, 0 of them with a penalty assessed. Federal and state penalties are separate figures from separate authorities and are shown as each was filed, never added together.
Informal enforcement
EPA’s informal enforcement file holds no action for NPDES TX0081337.
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Figures from EPA’s ICIS-NPDES download, loaded October 14, 2026.