Silverthorne Dillon Joint Sewer Authority — NPDES permit CO0020826: limits, due date and EPA's record

Sewage treatment plant, major discharger, Silverthorne, Colorado. NPDES permit CO0020826 expired Jun 30, 2020; its limits still apply. Last 12 months: no values over a limit. Source: EPA ECHO, Oct 22, 2026.

Limits in force (206)

Parameter	Statistic	Limit	Months	Outfall
Temperature, water deg. centigrade	maximum weekly average	report only (deg C)	all year	001
Temperature, water deg. centigrade	maximum weekly average	report only (deg C)	all year	001
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
Temperature, water deg. centigrade	daily maximum	report only (deg C)	all year	001
Temperature, water deg. centigrade	daily maximum	report only (deg C)	all year	001
BOD, 5-day, 20 deg. C	30-day average	≤ 30 mg/L	all year	001
BOD, 5-day, 20 deg. C	30-day average	≤ 30 mg/L	all year	001
BOD, 5-day, 20 deg. C	30-day average	≤ 30 mg/L	all year	001
BOD, 5-day, 20 deg. C	maximum 7-day average	≤ 45 mg/L	all year	001
BOD, 5-day, 20 deg. C	maximum 7-day average	≤ 45 mg/L	all year	001
BOD, 5-day, 20 deg. C	maximum 7-day average	≤ 45 mg/L	all year	001
pH	minimum	≥ 6 SU	all year	001
pH	minimum	≥ 6 SU	all year	001
pH	minimum	≥ 6 SU	all year	001
pH	maximum	≤ 9 SU	all year	001
pH	maximum	≤ 9 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	30-day average	≤ 30 mg/L	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
Solids, total suspended	maximum 7-day average	≤ 45 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	≤ 24 mg/L	Jun	001
Nitrogen, ammonia total [as N]	30-day average	≤ 28 mg/L	Aug	001
Nitrogen, ammonia total [as N]	30-day average	≤ 26 mg/L	Sep	001
Nitrogen, ammonia total [as N]	30-day average	≤ 40 mg/L	Jan	001
Nitrogen, ammonia total [as N]	30-day average	≤ 40 mg/L	Mar	001
Nitrogen, ammonia total [as N]	30-day average	≤ 25 mg/L	Jul	001
Nitrogen, ammonia total [as N]	30-day average	≤ 27 mg/L	Oct	001
Nitrogen, ammonia total [as N]	30-day average	≤ 40 mg/L	Feb	001
Nitrogen, ammonia total [as N]	30-day average	≤ 32 mg/L	Nov	001
Nitrogen, ammonia total [as N]	30-day average	≤ 35 mg/L	May	001
Nitrogen, ammonia total [as N]	30-day average	≤ 40 mg/L	Apr	001
Nitrogen, ammonia total [as N]	30-day average	≤ 13.6 mg/L	Jun	001
Nitrogen, ammonia total [as N]	30-day average	≤ 14.3 mg/L	Sep	001
Nitrogen, ammonia total [as N]	30-day average	≤ 15.3 mg/L	Aug	001
Nitrogen, ammonia total [as N]	30-day average	≤ 22 mg/L	Jan	001
Nitrogen, ammonia total [as N]	30-day average	≤ 13.8 mg/L	Jul	001
Nitrogen, ammonia total [as N]	30-day average	≤ 22 mg/L	Mar	001
Nitrogen, ammonia total [as N]	30-day average	≤ 14.8 mg/L	Oct	001
Nitrogen, ammonia total [as N]	30-day average	≤ 22 mg/L	Feb	001
Nitrogen, ammonia total [as N]	30-day average	≤ 17.6 mg/L	Nov	001
Nitrogen, ammonia total [as N]	30-day average	≤ 19.3 mg/L	May	001
Nitrogen, ammonia total [as N]	30-day average	≤ 22 mg/L	Apr	001
Nitrogen, ammonia total [as N]	30-day average	≤ 9.2 mg/L	Jun	001
Nitrogen, ammonia total [as N]	30-day average	≤ 10.3 mg/L	Aug	001
Nitrogen, ammonia total [as N]	30-day average	≤ 10.7 mg/L	Sep	001
Nitrogen, ammonia total [as N]	30-day average	≤ 14.9 mg/L	Jan	001
Nitrogen, ammonia total [as N]	30-day average	≤ 14.9 mg/L	Mar	001
Nitrogen, ammonia total [as N]	30-day average	≤ 9.3 mg/L	Jul	001
Nitrogen, ammonia total [as N]	30-day average	≤ 10 mg/L	Oct	001
Nitrogen, ammonia total [as N]	30-day average	≤ 14.9 mg/L	Feb	001
Nitrogen, ammonia total [as N]	30-day average	≤ 11.9 mg/L	Nov	001
Nitrogen, ammonia total [as N]	30-day average	≤ 13 mg/L	May	001
Nitrogen, ammonia total [as N]	30-day average	≤ 14.9 mg/L	Apr	001
Nitrogen, ammonia total [as N]	30-day average	≤ 22 mg/L	Dec	001
Nitrogen, ammonia total [as N]	30-day average	≤ 14.9 mg/L	Dec	001
Nitrogen, ammonia total [as N]	30-day average	≤ 40 mg/L	Dec	001
Nitrogen, ammonia total [as N]	daily maximum	≤ 180 mg/L	Jun	001
Nitrogen, ammonia total [as N]	daily maximum	≤ 105 mg/L	Aug	001
Nitrogen, ammonia total [as N]	daily maximum	≤ 150 mg/L	Sep	001
Nitrogen, ammonia total [as N]	daily maximum	≤ 82 mg/L	Jan	001
Nitrogen, ammonia total [as N]	daily maximum	≤ 125 mg/L	Mar	001
Nitrogen, ammonia total [as N]	daily maximum	≤ 135 mg/L	Jul	001
Nitrogen, ammonia total [as N]	daily maximum	≤ 120 mg/L	Oct	001
Nitrogen, ammonia total [as N]	daily maximum	≤ 91 mg/L	Feb	001
Nitrogen, ammonia total [as N]	daily maximum	≤ 105 mg/L	Nov	001
Nitrogen, ammonia total [as N]	daily maximum	≤ 44 mg/L	May	001
Nitrogen, ammonia total [as N]	daily maximum	≤ 86 mg/L	Apr	001
Nitrogen, ammonia total [as N]	daily maximum	≤ 105 mg/L	Jun	001
Nitrogen, ammonia total [as N]	daily maximum	≤ 92 mg/L	Sep	001
Nitrogen, ammonia total [as N]	daily maximum	≤ 60 mg/L	Aug	001
Nitrogen, ammonia total [as N]	daily maximum	≤ 48 mg/L	Jan	001
Nitrogen, ammonia total [as N]	daily maximum	≤ 81 mg/L	Jul	001
Nitrogen, ammonia total [as N]	daily maximum	≤ 75 mg/L	Mar	001
Nitrogen, ammonia total [as N]	daily maximum	≤ 73 mg/L	Oct	001
Nitrogen, ammonia total [as N]	daily maximum	≤ 54 mg/L	Feb	001
Nitrogen, ammonia total [as N]	daily maximum	≤ 63 mg/L	Nov	001
Nitrogen, ammonia total [as N]	daily maximum	≤ 26 mg/L	May	001
Nitrogen, ammonia total [as N]	daily maximum	≤ 51 mg/L	Apr	001
Nitrogen, ammonia total [as N]	daily maximum	≤ 78 mg/L	Jun	001
Nitrogen, ammonia total [as N]	daily maximum	≤ 46 mg/L	Aug	001
Nitrogen, ammonia total [as N]	daily maximum	≤ 67 mg/L	Sep	001
Nitrogen, ammonia total [as N]	daily maximum	≤ 35 mg/L	Jan	001
Nitrogen, ammonia total [as N]	daily maximum	≤ 54 mg/L	Mar	001
Nitrogen, ammonia total [as N]	daily maximum	≤ 58 mg/L	Jul	001
Nitrogen, ammonia total [as N]	daily maximum	≤ 53 mg/L	Oct	001
Nitrogen, ammonia total [as N]	daily maximum	≤ 39 mg/L	Feb	001
Nitrogen, ammonia total [as N]	daily maximum	≤ 45 mg/L	Nov	001
Nitrogen, ammonia total [as N]	daily maximum	≤ 19 mg/L	May	001
Nitrogen, ammonia total [as N]	daily maximum	≤ 37 mg/L	Apr	001
Nitrogen, ammonia total [as N]	daily maximum	≤ 49 mg/L	Dec	001
Nitrogen, ammonia total [as N]	daily maximum	≤ 36 mg/L	Dec	001
Nitrogen, ammonia total [as N]	daily maximum	≤ 83 mg/L	Dec	001
Phosphorus, total [as P]	aggregate rolling median	≤ 1.7 mg/L	all year	001
Phosphorus, total [as P]	aggregate rolling median	≤ 4.4 mg/L	all year	001
Phosphorus, total [as P]	aggregate rolling median	≤ 2.4 mg/L	all year	001
Cyanide, total [as CN]	annual average	report only (ug/L)	all year	001
Cyanide, total [as CN]	daily maximum	report only (ug/L)	all year	001
Arsenic, total [as As]	annual average	report only (ug/L)	all year	001
Arsenic, total [as As]	daily maximum	report only (ug/L)	all year	001
Cadmium, total [as Cd]	annual average	report only (ug/L)	all year	001
Cadmium, total [as Cd]	daily maximum	report only (ug/L)	all year	001
Chromium, total [as Cr]	annual average	report only (ug/L)	all year	001
Chromium, total [as Cr]	daily maximum	report only (ug/L)	all year	001
Copper, total [as Cu]	annual average	report only (ug/L)	all year	001
Copper, total [as Cu]	daily maximum	report only (ug/L)	all year	001
Lead, total [as Pb]	annual average	report only (ug/L)	all year	001
Lead, total [as Pb]	daily maximum	report only (ug/L)	all year	001
Molybdenum, total [as Mo]	annual average	report only (ug/L)	all year	001
Molybdenum, total [as Mo]	daily maximum	report only (ug/L)	all year	001
Nickel, total [as Ni]	annual average	report only (ug/L)	all year	001
Nickel, total [as Ni]	daily maximum	report only (ug/L)	all year	001
Silver, total [as Ag]	annual 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]	annual average	report only (ug/L)	all year	001
Zinc, total [as Zn]	daily maximum	report only (ug/L)	all year	001
Selenium, total [as Se]	annual average	report only (ug/L)	all year	001
Selenium, total [as Se]	daily maximum	report only (ug/L)	all year	001
Oil and grease	instantaneous maximum	≤ 10 mg/L	all year	001
Oil and grease	instantaneous maximum	≤ 10 mg/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
Flow, in conduit or thru treatment plant	30-day average	≤ 1.5 MGD	all year	001
Flow, in conduit or thru treatment plant	30-day average	≤ 2.7 MGD	all year	001
Flow, in conduit or thru treatment plant	30-day average	≤ 4 MGD	all year	001
Flow, in conduit or thru treatment plant	daily maximum	report only (MGD)	all year	001
Flow, in conduit or thru treatment plant	daily maximum	report only (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	≤ .095 mg/L	all year	001
Chlorine, total residual	30-day average	≤ .053 mg/L	all year	001
Chlorine, total residual	30-day average	≤ .036 mg/L	all year	001
Chlorine, total residual	instantaneous maximum	≤ .47 mg/L	all year	001
Chlorine, total residual	instantaneous maximum	≤ .27 mg/L	all year	001
Chlorine, total residual	instantaneous maximum	≤ .19 mg/L	all year	001
E. coli	30-day geometric mean	≤ 1507 #/100mL	all year	001
E. coli	30-day geometric mean	≤ 837 #/100mL	all year	001
E. coli	30-day geometric mean	≤ 565 #/100mL	all year	001
E. coli	maximum 7-day geometric mean	≤ 3014 #/100mL	all year	001
E. coli	maximum 7-day geometric mean	≤ 1674 #/100mL	all year	001
E. coli	maximum 7-day geometric mean	≤ 1130 #/100mL	all year	001
Nitrogen, Total As N	aggregate rolling median	≤ 36.6 mg/L	all year	001
Nitrogen, Total As N	aggregate rolling median	≤ 20.6 mg/L	all year	001
Nitrogen, Total As N	aggregate rolling median	report only (mg/L)	all year	001
Nitrogen, Total As N	aggregate rolling median	≤ 14.4 mg/L	all year	001
Nitrogen, Total As N	aggregate rolling median	report only (mg/L)	all year	001
Nonylphenol	30-day average	report only (ug/L)	all year	001
Nonylphenol	30-day average	report only (ug/L)	all year	001
Nonylphenol	daily maximum	report only (ug/L)	all year	001
Nonylphenol	daily maximum	report only (ug/L)	all year	001
Solids, total dissolved	30-day average	report only (mg/L)	all year	001
Solids, total dissolved	30-day average	report only (mg/L)	all year	001
Solids, total dissolved	30-day average	report only (mg/L)	all year	001
Solids, total dissolved	daily maximum	report only (mg/L)	all year	001
Solids, total dissolved	daily maximum	report only (mg/L)	all year	001
Solids, total dissolved	daily maximum	report only (mg/L)	all year	001
Solids, total dissolved	30-day average	report only (mg/L)	all year	001
Solids, total dissolved	30-day average	report only (mg/L)	all year	001
Solids, total dissolved	30-day average	report only (mg/L)	all year	001
Solids, total dissolved	daily maximum	report only (mg/L)	all year	001
Solids, total dissolved	daily maximum	report only (mg/L)	all year	001
Solids, total dissolved	daily maximum	report only (mg/L)	all year	001
Mercury, total [as Hg]	annual average	report only (ug/L)	all year	001
Mercury, total [as Hg]	daily maximum	report only (ug/L)	all year	001
BOD, 5-day, percent removal	monthly average minimum	≥ 85 %	all year	001
BOD, 5-day, percent removal	monthly average minimum	≥ 85 %	all year	001
BOD, 5-day, percent removal	monthly average minimum	≥ 85 %	all year	001
Solids, suspended percent removal	monthly average minimum	≥ 85 %	all year	001
Solids, suspended percent removal	monthly average minimum	≥ 85 %	all year	001
Solids, suspended percent removal	monthly average minimum	≥ 85 %	all year	001
Oil and grease visual	instantaneous maximum	report only (abst=0;prst=1)	all year	001
Oil and grease visual	instantaneous maximum	report only (abst=0;prst=1)	all year	001
Oil and grease visual	instantaneous maximum	report only (abst=0;prst=1)	all year	001
LC50 Static Renewal 48Hr Acute Ceriodaphnia dubia	minimum value	≥ 100 %	all year	001
LC50 Static Renewal 96Hr Acute Pimephales promelas	minimum value	≥ 100 %	all year	001
Lead, potentially dissolvd	30-day average	report only (ug/L)	all year	01B
Lead, potentially dissolvd	daily maximum	report only (ug/L)	all year	01B
Lead, potentially dissolvd	rolling average	report only (ug/L)	all year	01B
LC50 Static Renewal 48Hr Acute Ceriodaphnia dubia	minimum value	≥ 100 %	all year	01B
LC50 Static Renewal 96Hr Acute Pimephales promelas	minimum value	≥ 100 %	all year	01B
Copper, potentially dissolved	30-day average	report only (ug/L)	all year	01C
Copper, potentially dissolved	daily maximum	report only (ug/L)	all year	01C
Copper, potentially dissolved	rolling average	report only (ug/L)	all year	01C
Lead, potentially dissolvd	30-day average	report only (ug/L)	all year	01C
Lead, potentially dissolvd	daily maximum	report only (ug/L)	all year	01C
Lead, potentially dissolvd	rolling average	report only (ug/L)	all year	01C
Static Renewal 7 Day Chronic Ceriodaphnia dubia	single sample	report only (tox chronic)	all year	01C
Static Renewal 7 Day Chronic Ceriodaphnia dubia	minimum value	report only (tox chronic)	all year	01C
Static Renewal 7 Day Chronic Ceriodaphnia dubia	minimum value	≥ 9.4 tox chronic	all year	01C
Static Renewal 7 Day Chronic Pimephales promelas	single sample	report only (tox chronic)	all year	01C
Static Renewal 7 Day Chronic Pimephales promelas	minimum value	report only (tox chronic)	all year	01C
Static Renewal 7 Day Chronic Pimephales promelas	minimum value	≥ 9.4 tox chronic	all year	01C
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
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
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/CO0020826 · MCP: https://passage-data.com/mcp