5 Colo. Code Regs. § 1002-36.5
All waters of the Rio Grande Basin are subject to the following standard for temperature. (Discharges regulated by permits, which are within the permit limitations, shall not be subject to enforcement proceedings under this standard.) Temperature shall maintain a normal pattern of diurnal and seasonal fluctuations with no abrupt changes and shall have no increase in temperature of a magnitude, rate, and duration deemed deleterious to the resident aquatic life. This standard shall not be interpreted or applied in a manner inconsistent with section 25-8-104, C.R.S.
See Basic Standards and Methodologies for Surface Water for a listing of organic standards at 31.11 Table B and metal standards found at 31.16 Table III. The column in the tables headed "Water + Fish" are presumptively applied to all aquatic life class 1 streams which also have a water supply classification, and are applied to aquatic life class 2 streams which also have a water supply classification, on a case-by-case basis as shown in Appendix 36-1. The column in the tables at 31.11 and 31.16 Table III headed "Fish Ingestion" is presumptively applied to all aquatic life class 1 streams which do not have a water supply classification, and are applied to aquatic life class 2 streams which do not have a water supply classification, on a case-by-case basis as shown in Appendix 36-1.
Prior to December 31, 2022 for chlorophyll a and prior to December 31, 2027 for total phosphorus, interim nutrient values will be considered for adoption only in the limited circumstances defined at 31.17(e) and (f). These circumstances include headwaters, Direct Use Water Supply (DUWS) Lakes and Reservoirs, and other special circumstances determined by the Commission. Additionally, prior to December 31, 2027, only total phosphorus and chlorophyll a will be considered for adoption. After December 31, 2027, total nitrogen will be considered for adoption per the circumstances outlined in 31.17(g).
Prior to December 31, 2027, nutrient criteria will be adopted for headwaters on a segment by segment basis for the Rio Grande Basin. Moreover, pursuant to 31.17(e) nutrient standards will only be adopted for waters upstream of all permitted domestic wastewater treatment facilities discharging prior to May 31, 2012 or with preliminary effluent limits requested prior to May 31, 2012, and any non-domestic facilities subject to Regulation 85 effluent limits and discharging prior to May 31, 2012. The following is a list of all permitted domestic wastewater treatment facilities discharging prior to May 31, 2012 or with preliminary effluent limits requested prior to May 31, 2012, and any non-domestic facilities subject to Regulation 85 effluent limits and discharging prior to May 31, 2012 in the Rio Grande Basin:
Segment | Permittee | Facility name | Permit No. |
CORGRG02 | Mountain Views at Rivers Edge RV | Mtn Views At Rvrs Edge Rv Rst | COG588069 |
CORGRG04b | South Fork Water and Sanitation District | South Fork Water and San Dist WWTF | COG588039 |
CORGRG04c | Monte Vista City of | Veterans Center WWTF | CO0036927 |
CORGRG04c ;CORGRG15 | Monte Vista City of | Henderson Lagoon Facility | CO0023132 |
CORGRG04b ;CORGRG18 | Del Norte Town of | Del Norte WWTF | CO0020281 |
CORGRG07 | Creede City of | Creede WWTF | CO0040533 |
CORGRG09b | Fun Valley Resort | Fun Valley Resort | COG588018 |
CORGRG09a | Wolf Creek Ski Corp | Wolf Creek Ski Corp WWTF | CO0041785 |
CORGRG12 | Alamosa City of | Alamosa Regional WWTF | CO0044458 |
CORGRG15 | San Luis Water and Sanitation District | San Luis Water and San Dist WWTF | COG589082 |
CORGRG31 | Costilla County Water and Sanitation System | Costilla County Water & San Dist WWTF | CO0036528 |
CORGAL12 | La Jara Town of | La Jara WWTF | CO0020150 |
CORGAL15 | Manassa Town of | Manassa WWTF | CO0042935 |
CORGAL18 | Antonito Town of | Antonito WWTF | CO0040975 |
CORGCB06 | Baca Grande Water and Sanitation District | Aspen Institute | CO0046914 |
Prior to May 31, 2022:
* For segments located entirely above these facilities, nutrient standards apply to the entire segment.
* For segments with portions downstream of these facilities, nutrient standards only apply above these facilities. A note was added to the total phosphorus and chlorophyll a standards in these segments. The note references the table of qualified facilities at 36.5(4).
* For segments located entirely below these facilities, nutrient standards do not apply.
A note was added to the total phosphorus and chlorophyll a standards in lakes segments as nutrients standards apply only to lakes and reservoirs larger than 25 acres surface area.
5 CCR 1002-36.5