Metro Water Recovery — NPDES permit CO0026638: limits, due date and EPA's record

Sewage treatment plant, major discharger, Denver, Colorado. NPDES permit CO0026638 expired Jun 30, 2023; its limits still apply. Last 12 months: over a limit once (last April 2026), 4 of 55 reports late. Source: EPA ECHO, Oct 22, 2026.

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

Period ending	Parameter	Reported	Limit	Over by
April 2026	Static Renewal 7 Day Chronic Ceriodaphnia dubia, minimum value	91.6 tox chronic	≥ 99 tox chronic	7%

Limits in force (171)

Parameter	Statistic	Limit	Months	Outfall
Temperature, water deg. centigrade	maximum weekly average	report only (deg C)	all year	001
Temperature, water deg. centigrade	daily maximum	report only (deg C)	all year	001
Oxygen, dissolved [DO]	instantaneous minimum	≥ 3 mg/L	all year	001
Oxygen, dissolved [DO]	minimum 7-day average	≥ 5 mg/L	all year	001
pH	minimum	≥ 6 SU	all year	001
pH	maximum	≤ 9 SU	all year	001
Solids, total suspended	30-day average	≤ 30 mg/L	all year	001
Solids, total suspended	maximum 7-day average	≤ 45 mg/L	all year	001
Nitrogen, ammonia total [as N]	30-day average	≤ 5.7 mg/L	Jan	001
Nitrogen, ammonia total [as N]	30-day average	≤ 6.1 mg/L	Feb	001
Nitrogen, ammonia total [as N]	30-day average	≤ 5.6 mg/L	Mar	001
Nitrogen, ammonia total [as N]	30-day average	≤ 5 mg/L	Apr	001
Nitrogen, ammonia total [as N]	30-day average	≤ 3.8 mg/L	May	001
Nitrogen, ammonia total [as N]	30-day average	≤ 3.8 mg/L	Jun	001
Nitrogen, ammonia total [as N]	30-day average	≤ 3.4 mg/L	Jul	001
Nitrogen, ammonia total [as N]	30-day average	≤ 3.2 mg/L	Aug	001
Nitrogen, ammonia total [as N]	30-day average	≤ 3.3 mg/L	Sep	001
Nitrogen, ammonia total [as N]	30-day average	≤ 3.9 mg/L	Oct	001
Nitrogen, ammonia total [as N]	30-day average	≤ 4.4 mg/L	Nov	001
Nitrogen, ammonia total [as N]	30-day average	≤ 5.1 mg/L	Dec	001
Nitrogen, ammonia total [as N]	daily maximum	≤ 8.1 mg/L	Jan	001
Nitrogen, ammonia total [as N]	daily maximum	≤ 7.1 mg/L	Oct	001
Nitrogen, ammonia total [as N]	daily maximum	≤ 10 mg/L	Nov	001
Nitrogen, ammonia total [as N]	daily maximum	≤ 7.8 mg/L	Feb	001
Nitrogen, ammonia total [as N]	daily maximum	≤ 8 mg/L	Mar	001
Nitrogen, ammonia total [as N]	daily maximum	≤ 13 mg/L	Apr	001
Nitrogen, ammonia total [as N]	daily maximum	≤ 9.5 mg/L	May	001
Nitrogen, ammonia total [as N]	daily maximum	≤ 7.3 mg/L	Jun	001
Nitrogen, ammonia total [as N]	daily maximum	≤ 7.7 mg/L	Jul	001
Nitrogen, ammonia total [as N]	daily maximum	≤ 7.9 mg/L	Aug	001
Nitrogen, ammonia total [as N]	daily maximum	≤ 7.5 mg/L	Sep	001
Nitrogen, ammonia total [as N]	daily maximum	≤ 9.2 mg/L	Dec	001
Nitrite + Nitrate total [as N]	daily maximum	≤ 9.8 mg/L	Jan	001
Nitrite + Nitrate total [as N]	daily maximum	≤ 9.5 mg/L	Feb	001
Nitrite + Nitrate total [as N]	daily maximum	≤ 9.6 mg/L	Mar	001
Nitrite + Nitrate total [as N]	daily maximum	≤ 10 mg/L	Apr	001
Nitrite + Nitrate total [as N]	daily maximum	≤ 10 mg/L	May	001
Nitrite + Nitrate total [as N]	daily maximum	≤ 9.7 mg/L	Jun	001
Nitrite + Nitrate total [as N]	daily maximum	≤ 9.6 mg/L	Jul	001
Nitrite + Nitrate total [as N]	daily maximum	≤ 10 mg/L	Aug	001
Nitrite + Nitrate total [as N]	daily maximum	≤ 10 mg/L	Sep	001
Nitrite + Nitrate total [as N]	daily maximum	≤ 9.9 mg/L	Oct	001
Nitrite + Nitrate total [as N]	daily maximum	≤ 9.8 mg/L	Nov	001
Nitrite + Nitrate total [as N]	daily maximum	≤ 9.8 mg/L	Dec	001
Nitrogen, inorganic total	annual median	≤ 15 mg/L	all year	001
Nitrogen, inorganic total	95th percentile	≤ 20 mg/L	all year	001
Phosphorus, total [as P]	annual median	report only (mg/L)	all year	001
Phosphorus, total [as P]	annual median	≤ 1 mg/L	all year	001
Phosphorus, total [as P]	95th percentile	report only (mg/L)	all year	001
Phosphorus, total [as P]	95th percentile	≤ 2.5 mg/L	all year	001
Cyanide, weak acid, dissociable	daily maximum	≤ 5 ug/L	all year	001
Cyanide, total [as CN]	daily maximum	report only (ug/L)	all year	001
Chloride [as Cl]	30-day average	report only (mg/L)	all year	001
Arsenic, total recoverable	30-day average	report only (ug/L)	all year	001
Iron, total recoverable	30-day average	report only (ug/L)	all year	001
Iron, total recoverable	30-day average	≤ 1000 ug/L	all year	001
Arsenic, total [as As]	daily maximum	report only (ug/L)	all year	001
Beryllium, total [as Be]	daily maximum	report only (ug/L)	all year	001
Cadmium, total [as Cd]	daily maximum	report only (ug/L)	all year	001
Chromium, total [as Cr]	30-day average	report only (ug/L)	all year	001
Chromium, total [as Cr]	daily maximum	report only (ug/L)	all year	001
Chromium, total [as Cr]	daily maximum	report only (ug/L)	all year	001
Copper, total [as Cu]	daily maximum	report only (ug/L)	all year	001
Iron, dissolved [as Fe]	30-day average	report only (ug/L)	all year	001
Iron, dissolved [as Fe]	30-day average	≤ 300 ug/L	all year	001
Lead, total [as Pb]	daily maximum	report only (ug/L)	all year	001
Manganese, total [as Mn]	30-day average	report only (ug/L)	all year	001
Manganese, total [as Mn]	daily maximum	report only (ug/L)	all year	001
Thallium, total [as Tl]	daily maximum	report only (ug/L)	all year	001
Molybdenum, total [as Mo]	daily maximum	report only (ug/L)	all year	001
Nickel, total [as Ni]	daily maximum	report only (ug/L)	all year	001
Nickel, total recoverable	30-day average	report only (ug/L)	all year	001
Silver, total [as Ag]	daily maximum	report only (ug/L)	all year	001
Zinc, total [as Zn]	daily maximum	report only (ug/L)	all year	001
Antimony, total [as Sb]	daily maximum	report only (ug/L)	all year	001
Cadmium, total recoverable	daily maximum	report only (ug/L)	all year	001
Lead, total recoverable	daily maximum	report only (ug/L)	all year	001
Molybdenum, total recoverable	30-day average	report only (ug/L)	all year	001
Selenium, total [as Se]	daily maximum	report only (ug/L)	all year	001
Zinc, potentially dissolved	30-day average	report only (ug/L)	all year	001
Zinc, potentially dissolved	daily maximum	report only (ug/L)	all year	001
Silver, potentially dissolved	30-day average	report only (ug/L)	all year	001
Silver, potentially dissolved	daily maximum	report only (ug/L)	all year	001
Copper, potentially dissolved	30-day average	report only (ug/L)	all year	001
Copper, potentially dissolved	daily maximum	report only (ug/L)	all year	001
Arsenic, potentially dissolved	daily maximum	report only (ug/L)	all year	001
Cadmium, potentially dissolvd	30-day average	report only (ug/L)	Jan, Feb, Mar, Apr, May, Jul, Aug, Sep, Oct, Nov, Dec	001
Cadmium, potentially dissolvd	30-day average	report only (ug/L)	Jun	001
Cadmium, potentially dissolvd	daily maximum	report only (ug/L)	Jan, Feb, Mar, Apr, May, Jul, Aug, Sep, Oct, Nov, Dec	001
Cadmium, potentially dissolvd	daily maximum	report only (ug/L)	Jun	001
Cadmium, potentially dissolvd	30-day average	≤ 1.21 lb/d	Jan, Feb, Mar, Apr, May, Jul, Aug, Sep, Oct, Nov, Dec	001
Cadmium, potentially dissolvd	30-day average	≤ 1.12 lb/d	Jun	001
Lead, potentially dissolvd	30-day average	report only (ug/L)	all year	001
Lead, potentially dissolvd	daily maximum	report only (ug/L)	all year	001
Nickel, potentially dissolvd	30-day average	report only (ug/L)	all year	001
Nickel, potentially dissolvd	daily maximum	report only (ug/L)	all year	001
Selenium, potentially dissolvd	30-day average	report only (ug/L)	all year	001
Selenium, potentially dissolvd	daily maximum	report only (ug/L)	all year	001
Oil and grease	instantaneous maximum	≤ 10 mg/L	all year	001
Total phenols	daily maximum	report only (ug/L)	all year	001
Tetrachloroethylene	30-day average	report only (ug/L)	all year	001
Flow, in conduit or thru treatment plant	30-day average	≤ 220 MGD	all year	001
Flow, in conduit or thru treatment plant	daily maximum	report only (MGD)	all year	001
Chlorine, total residual	30-day average	≤ .011 mg/L	all year	001
Chlorine, total residual	daily maximum	≤ .019 mg/L	all year	001
Mercury, total [low level]	30-day average	report only (ug/L)	all year	001
E. coli	30-day geometric mean	≤ 126 #/100mL	all year	001
E. coli	maximum 7-day geometric mean	≤ 252 #/100mL	all year	001
Nonylphenol	30-day average	report only (ug/L)	all year	001
Nonylphenol	daily maximum	report only (ug/L)	all year	001
Mercury, total [as Hg]	daily maximum	report only (ug/L)	all year	001
BOD, carbonaceous [5 day, 20 C]	30-day average	≤ 17 mg/L	all year	001
BOD, carbonaceous [5 day, 20 C]	maximum 7-day average	≤ 25 mg/L	all year	001
BOD, carb-5 day, 20 deg C, percent removal	monthly average minimum	≥ 85 %	all year	001
Solids, suspended percent removal	monthly average minimum	≥ 85 %	all year	001
Sulfate	30-day average	report only (mg/L)	all year	001
Oil and grease visual	instantaneous maximum	report only (abst=0;prst=1)	all year	001
Static Renewal 7 Day Chronic Ceriodaphnia dubia	single sample	report only (tox chronic)	all year	001
Static Renewal 7 Day Chronic Ceriodaphnia dubia	single sample	report only (tox chronic)	all year	001
Static Renewal 7 Day Chronic Ceriodaphnia dubia	single sample	report only (tox chronic)	all year	001
Static Renewal 7 Day Chronic Ceriodaphnia dubia	single sample	report only (tox chronic)	all year	001
Static Renewal 7 Day Chronic Ceriodaphnia dubia	minimum value	report only (tox chronic)	all year	001
Static Renewal 7 Day Chronic Ceriodaphnia dubia	minimum value	report only (tox chronic)	all year	001
Static Renewal 7 Day Chronic Ceriodaphnia dubia	minimum value	report only (tox chronic)	all year	001
Static Renewal 7 Day Chronic Ceriodaphnia dubia	minimum value	report only (tox chronic)	all year	001
Static Renewal 7 Day Chronic Ceriodaphnia dubia	minimum value	≥ 99 tox chronic	all year	001
Static Renewal 7 Day Chronic Ceriodaphnia dubia	minimum value	≥ 99 tox chronic	all year	001
Static Renewal 7 Day Chronic Ceriodaphnia dubia	minimum value	≥ 99 tox chronic	all year	001
Static Renewal 7 Day Chronic Ceriodaphnia dubia	minimum value	≥ 99 tox chronic	all year	001
Static Renewal 7 Day Chronic Pimephales promelas	single sample	report only (tox chronic)	all year	001
Static Renewal 7 Day Chronic Pimephales promelas	single sample	report only (tox chronic)	all year	001
Static Renewal 7 Day Chronic Pimephales promelas	single sample	report only (tox chronic)	all year	001
Static Renewal 7 Day Chronic Pimephales promelas	single sample	report only (tox chronic)	all year	001
Static Renewal 7 Day Chronic Pimephales promelas	minimum value	report only (tox chronic)	all year	001
Static Renewal 7 Day Chronic Pimephales promelas	minimum value	report only (tox chronic)	all year	001
Static Renewal 7 Day Chronic Pimephales promelas	minimum value	report only (tox chronic)	all year	001
Static Renewal 7 Day Chronic Pimephales promelas	minimum value	report only (tox chronic)	all year	001
Static Renewal 7 Day Chronic Pimephales promelas	minimum value	≥ 99 tox chronic	all year	001
Static Renewal 7 Day Chronic Pimephales promelas	minimum value	≥ 99 tox chronic	all year	001
Static Renewal 7 Day Chronic Pimephales promelas	minimum value	≥ 99 tox chronic	all year	001
Static Renewal 7 Day Chronic Pimephales promelas	minimum value	≥ 99 tox chronic	all year	001
Plant capacity fact. percent of capacity	30-day average	report only (%)	all year	300
Plant capacity fact. percent of capacity	30-day average	report only (%)	all year	300
BOD, 5-day, 20 deg. C	30-day average	report only (mg/L)	all year	300
BOD, 5-day, 20 deg. C	maximum 7-day average	report only (mg/L)	all year	300
BOD, 5-day, 20 deg. C	30-day average	report only (lb/d)	all year	300
BOD, 5-day, 20 deg. C	maximum 7-day average	report only (lb/d)	all year	300
Solids, total suspended	30-day average	report only (mg/L)	all year	300
Solids, total suspended	maximum 7-day average	report only (mg/L)	all year	300
Cyanide, total [as CN]	daily maximum	report only (ug/L)	all year	300
Arsenic, total [as As]	daily maximum	report only (ug/L)	all year	300
Beryllium, total [as Be]	daily maximum	report only (ug/L)	all year	300
Cadmium, total [as Cd]	daily maximum	report only (ug/L)	all year	300
Chromium, total [as Cr]	daily maximum	report only (ug/L)	all year	300
Copper, total [as Cu]	daily maximum	report only (ug/L)	all year	300
Lead, total [as Pb]	daily maximum	report only (ug/L)	all year	300
Thallium, total [as Tl]	daily maximum	report only (ug/L)	all year	300
Molybdenum, total [as Mo]	daily maximum	report only (ug/L)	all year	300
Nickel, total [as Ni]	daily maximum	report only (ug/L)	all year	300
Silver, total [as Ag]	daily maximum	report only (ug/L)	all year	300
Zinc, total [as Zn]	daily maximum	report only (ug/L)	all year	300
Antimony, total [as Sb]	daily maximum	report only (ug/L)	all year	300
Selenium, total [as Se]	daily maximum	report only (ug/L)	all year	300
Total phenols	daily maximum	report only (ug/L)	all year	300
Flow, in conduit or thru treatment plant	30-day average	report only (MGD)	all year	300
Flow, in conduit or thru treatment plant	daily maximum	report only (MGD)	all year	300
Mercury, total [as Hg]	daily maximum	report only (ug/L)	all year	300
BOD, carbonaceous [5 day, 20 C]	30-day average	report only (mg/L)	all year	300
BOD, carbonaceous [5 day, 20 C]	maximum 7-day average	report only (mg/L)	all year	300
Temperature, water deg. centigrade	maximum weekly average	report only (deg C)	all year	UST1
Temperature, water deg. centigrade	daily maximum	report only (deg C)	all year	UST1

How strict are these limits?

Your permit document is the final word. As JSON: /api/v1/permits/CO0026638 · MCP: https://passage-data.com/mcp