Colo. Rev. Stat. § 25-8-103 (2026)

As used in this article 8, unless the context otherwise requires: (1) "Agricultural chemical" means any of the following: (a) A pesticide as defined in section 35-10-103, C.R.S.; or (b) A commercial fertilizer as defined in section 35-12-103, C.R.S. (1.1) "Agricultural management area" means a designated geographic area defined by the commissioner of agriculture that includes natural or man-made features where there is a significant risk of contamination or pollution of state waters from agricultural activities conducted at or near the land surface. (1.2) "Agricultural management plan" means any activity, procedure, or practice adopted as a rule by the commissioner of agriculture pursuant to article 4 of title 24, in consultation with the Colorado cooperative extension service established pursuant to part 7 of article 31 of title 23 and the water quality control division, to prevent or remedy the introduction of agricultural chemicals into state waters to the extent technically and economically practical. (1.3) "Best management practices" means any voluntary activity, procedure, or practice established by the department of agriculture, in consultation with the Colorado cooperative extension service established pursuant to part 7 of article 31 of title 23 and the water quality control division, to prevent or remedy the introduction of agricultural chemicals into state waters to the extent technically and economically practical. (1.4) "Biosolids" means the accumulated residual product resulting from a domestic wastewater treatment works or other domestic sources. "Biosolids" does not include grit or screenings from a wastewater treatment works or commercial and industrial septage or on-site wastewater treatment systems regulated by article 10 of this title. (1.5) "Commission" means the water quality control commission created by section 25- 8-201. (1.7) "Commissioner" means the commissioner of agriculture. (2) "Control regulation" means any regulation promulgated by the commission pursuant to section 25-8-205. (3) "Discharge of pollutants" means the introduction or addition of a pollutant into state waters. (4) "Division" means the division of administration of the department of public health and environment. (5) "Domestic wastewater treatment works" means a system or facility for treating, neutralizing, stabilizing, or disposing of domestic wastewater which system or facility has a designed capacity to receive more than two thousand gallons of domestic wastewater per day. The term "domestic wastewater treatment works" also includes appurtenances to such system or facility, such as outfall sewers and pumping stations, and to equipment related to such appurtenances. The term "domestic wastewater treatment works" does not include industrial wastewater treatment plants or complexes whose primary function is the treatment of industrial wastes, notwithstanding the fact that human wastes generated incidentally to the industrial processes are treated therein. (6) "Effluent limitation" means any restriction or prohibition established under this article or federal law on quantities, rates, and concentrations of chemical, physical, biological, and other constituents which are discharged from point sources into state waters, including, but not limited to, standards of performance for new sources, toxic effluent standards, and schedules of compliance. (7) "Executive director" means the executive director of the department of public health and environment. (8) "Federal act" means the "Federal Water Pollution Control Act", commonly referred to as the "Clean Water Act". (8.3) (a) "Graywater" means that portion of wastewater that, before being treated or combined with other wastewater, is collected from fixtures within residential, commercial, or industrial buildings or institutional facilities for the purpose of being put to beneficial uses authorized by the commission in accordance with section 25-8-205 (1)(g); except that graywater use for purposes of scientific research must comply with the requirements of section 25-8-205.3, but need not comply with the commission's control regulations established under section 25-8- 205 (1). (b) Sources of graywater may include discharges from bathroom and laundry room sinks, bathtubs, showers, laundry machines, and other sources authorized by rule. Graywater does not include the wastewater from toilets, urinals, kitchen sinks, dishwashers, or nonlaundry utility sinks. Graywater must be collected in a manner that minimizes household wastes, human excreta, animal or vegetable matter, and chemicals that are hazardous or toxic, as determined by the commission; except that a person may collect, treat, and use graywater in a manner that departs from the commission's control regulations established under section 25-8-205 (1) if the person collects, treats, and uses graywater for purposes of scientific research in accordance with the requirements of section 25-8-205.3. (8.4) "Graywater treatment works" means an arrangement of devices and structures used to: (a) Collect graywater from within a building or a facility; and (b) Treat, neutralize, or stabilize graywater within the same building or facility to the level necessary for its authorized uses. (8.5) "Industrial discharger" means any entity which introduces pollutants into a domestic wastewater treatment works from any nondomestic source subject to regulation under section 307 (b), (c), or (d) of the federal act. (9) "Irrigation return flow" means tailwater, tile drainage, or surfaced groundwater flow from irrigated land. (10) "Issue" or "issuance" means the mailing to all parties of any order, permit, determination, or notice, other than notice by publication, by certified mail to the last address furnished to the agency by the person subject thereto or personal service on such person, and the date of issuance of such order, permit, determination, or notice shall be the date of such mailing or service or such later date as is stated in the order, permit, determination, or notice. (11) "Municipality" means any regional commission, county, metropolitan district offering sanitation service, sanitation district, water and sanitation district, water conservancy district, metropolitan sewage disposal district, service authority, city and county, city, town, Indian tribe or authorized Indian tribal organization, or any two or more of them which are acting jointly in connection with a sewage treatment works. (12) "Permit" means a permit issued pursuant to part 5 of this article. (13) "Person" means an individual, corporation, partnership, association, state or political subdivision thereof, federal agency, state agency, municipality, commission, or interstate body. (14) "Point source" means any discernible, confined, and discrete conveyance, including, but not limited to, any pipe, ditch, channel, tunnel, conduit, well, discrete fissure, container, rolling stock, concentrated animal feeding operation, or vessel or other floating craft, from which pollutants are or may be discharged. "Point source" does not include irrigation return flow. (15) "Pollutant" means dredged spoil, dirt, slurry, solid waste, incinerator residue, sewage, sewage sludge, garbage, trash, chemical waste, biological nutrient, biological material, radioactive material, heat, wrecked or discarded equipment, rock, sand, or any industrial, municipal, or agricultural waste. (16) "Pollution" means the man-made, man-induced, or natural alteration of the physical, chemical, biological, and radiological integrity of water. (16.5) "Pretreatment requirement and standard" means any requirement, prohibition, standard, concentration, or effluent limitation described in enforceable pretreatment requirements by the commission pursuant to section 25-8-205 (1)(b), (1)(c), or (1)(d). (17) "Promulgate" means and includes authority to adopt, and from time to time amend, repeal, modify, publish, and put into effect. (17.5) "Reclaimed domestic wastewater" means wastewater that has received treatment in accordance with section 25-8-205.7, 25-8-205.8, or 25-8-205.9 and that enables the wastewater to meet the requirements, prohibitions, standards, and concentration limitations adopted by the commission for subsequent reuses other than drinking. (18) "Schedule of compliance" means a schedule of remedial measures and times including an enforceable sequence of actions or operations leading to compliance with any control regulation or effluent limitation. (19) "State waters" means any and all surface and subsurface waters that are contained in or flow in or through this state, including wetlands, but does not include waters in sewage systems, waters in treatment works of disposal systems, waters in potable water distribution systems, and all water withdrawn for use until use and treatment have been completed. (20) "Water quality standard" means any standard promulgated pursuant to section 25-8- 204.

Source: L. 81: Entire article R&RE, p. 1311, § 1, effective July 1. L. 90: (1) R&RE and (1.1) to (1.3), (1.5), (1.7), (8.5), and (16.5) added, pp. 1329, 1337, §§ 1, 2, 1, effective July 1. L. 93: (1.4) added, p. 1578, § 1, effective July 1. L. 94: (4) and (7) amended, p. 2789, § 517, effective July 1. L. 2000: (17.5) added, p. 252, § 1, effective March 31. L. 2012: (1.4) amended, (HB 12-1126), ch. 137, p. 494, § 3, effective August 8. L. 2013: (8.3) and (8.4) added, (HB 13- 1044), ch. 228, p. 1088, § 2, effective May 15. L. 2017: IP and (8.3) amended, (HB 17-1008), ch. 199, p. 722, § 1, effective August 9. L. 2018: (17.5) amended, (SB 18-038), ch. 400, p. 2365, § 1, effective August 8; (17.5) amended, (HB 18-1069), ch. 179, p. 1220, § 1, effective August 8; (17.5) amended, (HB 18-1093), ch. 171, p. 1197, § 1, effective August 8. L. 2019: (1.1), (1.2), and (1.3) amended, (SB 19-186), ch. 422, p. 3688, § 1, effective August 2. L. 2024: (19) amended, (HB 24-1379), ch. 274, p. 1823, § 3, effective May 29.

Editor's note: Amendments to subsection (17.5) by SB 18-038, HB 18-1069, and HB 18-1093 were harmonized.

Cross references: (1) For the "Federal Water Pollution Control Act" or "Clean Water Act", see 33 U.S.C. § 1251 et seq. (2) For the legislative declaration contained in the 1994 act amending subsections (4) and (7), see section 1 of chapter 345, Session Laws of Colorado 1994. For the legislative declaration in the 2013 act adding subsections (8.3) and (8.4), see section 1 of chapter 228, Session Laws of Colorado 2013.