(1) The commission may promulgate control
regulations for the following purposes:
(a) To describe prohibitions, standards, concentrations, and effluent
limitations on the extent of specifically identified pollutants, including, but not
limited to, those mentioned in section 25-8-204, that any person may discharge into
any specified class of state waters;
(b) To describe pretreatment requirements, prohibitions, standards,
concentrations, and effluent limitations on wastes any person may discharge into
any specified class of state water from any specified type of facility, process,
activity, or waste pile including, but not limited to, all types specified in section 306
(b)(1)(A) of the federal act;
(c) To describe precautionary measures, both mandatory and prohibitory,
that must be taken by any person owning, operating, conducting, or maintaining any
facility, process, activity, or waste pile that does cause or could reasonably be
expected to cause pollution of any state waters in violation of control regulations or
that does cause the quality of any state waters to be in violation of any applicable
water quality standard;
(d) To adopt toxic effluent standards and pretreatment standards for
pollutants which interfere with, pass through, or are otherwise incompatible with
sewage treatment works;
(e) [ Editor's note: This version of subsection (1)(e) is effective until July 1,
2026. ] To describe requirements, prohibitions, standards, and concentration
limitations on the use and disposal of biosolids to protect public health and to
prevent the discharge of pollutants into state waters, except as authorized by
permit. The commission requirements described pursuant to this paragraph (e) shall
be no more restrictive than the requirements adopted for solid wastes disposal
sites and facilities pursuant to part 1 of article 20 of title 30, C.R.S., except as
necessary to be consistent with section 405 of the federal act. Fees shall be
established as set forth in section 30-20-110.5, C.R.S., and the commission shall
have no authority to levy additional or duplicative fees.
(e) [ Editor's note: This version of subsection (1)(e) is effective July 1, 2026. ] To describe requirements, prohibitions, standards, and concentration limitations on
the use and disposal of biosolids to protect public health and to prevent the
discharge of pollutants into state waters, except as authorized by permit. The
commission requirements described pursuant to this subsection (1)(e) must not be
more restrictive than the requirements adopted for solid wastes disposal sites and
facilities pursuant to part 1 of article 20 of title 30, except as necessary to be
consistent with section 405 of the federal act. Fees must be established as set
forth in rules adopted by the commission pursuant to section 25-8-210.
(f) In accordance with sections 25-8-205.7, 25-8-205.8, and 25-8-205.9, to
describe requirements, prohibitions, standards, and concentration limitations on the
reuse of reclaimed domestic wastewater for purposes other than drinking that will
protect public health and encourage the reuse of reclaimed domestic wastewater;
(g) [ Editor's note: This version of subsection (1)(g) is effective until January 1,
2026. ]
(I) To describe requirements, prohibitions, and standards for the use of graywater
for nondrinking purposes, to encourage the use of graywater, and to protect public
health and water quality.
(II) Except as authorized in section 25-8-205.3, graywater may be used only
in areas where the local city, city and county, or county has adopted an ordinance or
resolution approving the use of graywater pursuant to section 30-11-107 (1)(kk) or
31-15-601 (1)(m). The city, city and county, or county that has adopted an ordinance
or resolution approving the use of graywater pursuant to section 30-11-107 (1)(kk) or
31-15-601 (1)(m) has exclusive enforcement authority regarding compliance with the
ordinance or resolution.
(III) Use of graywater shall be allowed only in accordance with the terms and
conditions of the decrees, contracts, and well permits applicable to the use of the
source water rights or source water and any return flows therefrom, and no use of
graywater shall be allowed that would not be allowed under such decrees,
contracts, or permits if the graywater ordinance or resolution did not exist.
(IV) A local city, city and county, or county may only authorize the use of
graywater in accordance with federal, state, and local requirements.
(g) [ Editor's note: This version of subsection (1)(g) is effective January 1,
2026. ]
(I) To describe requirements, prohibitions, and standards for the use of graywater
for nondrinking purposes, to encourage the use of graywater, and to protect public
health and water quality.
(II) A city, city and county, or county that has adopted an ordinance or
resolution regarding the use of graywater pursuant to section 30-11-107 (1)(kk) or
31-15-601 (1)(m) has exclusive enforcement authority regarding compliance with the
ordinance or resolution.
(III) Use of graywater is allowed only in accordance with the terms and
conditions of the decrees, contracts, and well permits applicable to the use of the
source water rights or source water and any return flows from the source water,
and graywater use shall not be allowed in a manner that is not allowed under such
decrees, contracts, or permits.
(h) In accordance with section 25-8-205.1, to establish requirements,
prohibitions, and standards for the discharge of dredged or fill material into state
waters.
(2) In the formulation of each control regulation, the commission shall
consider the following:
(a) The need for regulations that control discharges of specified pollutants
that are the subject of water quality standards for the receiving state waters;
(b) The need for regulations that specify treatment requirements for various
types of discharges;
(c) The degree to which any particular type of discharge is subject to
treatment, the availability, practicality, and technical and economic feasibility of
treatment techniques, and the extent to which the discharge to be controlled is
significant;
(d) Control requirements promulgated by agencies of the federal
government;
(e) The continuous, intermittent, or seasonal nature of the discharge to be
controlled;
(f) Whether a regulation that is to be applicable to discharges into flowing
water should be written in such a way that the degree of pollution tolerated or
treatment required will be dependent upon the volume of flow of the receiving
water or the extent to which the discharge is diluted therein, or the capacity of the
receiving water to assimilate the discharge; and
(g) The need for specification of safety precautions that should be taken to
protect water quality including, but not limited to, requirements for the keeping of
logs and other records, requirements to protect subsurface waters in connection
with mining and the drilling and operation of wells, and requirements as to settling
ponds, holding tanks, and other treatment facilities for water that will or might
enter state waters.
(3) Control regulations may be promulgated for use in connection with any
one or more of the classes of state waters authorized pursuant to section 25-8-203
and may be made applicable with respect to any designated portion of state waters
or to all state waters.
(4) The commission shall coordinate and cooperate with the state engineer,
the Colorado water conservation board, the energy and carbon management
commission created in section 34-60-104.3 (1), the state board of health, and other
state agencies having regulatory powers in order to avoid adopting control
regulations that would be either redundant or unnecessary.
(5) The commission shall not adopt control regulations that require
agricultural nonpoint source dischargers to utilize treatment techniques that
require additional consumptive or evaporative use which would cause material
injury to water rights. With regard to nonpoint source water pollution control
related to agricultural practices, the commission and division shall pursue incentive,
grant, and cooperative programs in preference to the promulgation of control
regulations. When interested water conservation districts, water conservancy
districts, and conservation districts recommend nonpoint source control activities
related to agricultural practices to the division and commission, the division and
commission, after consultation with such districts, shall give substantial weight to
the recommendations of such districts into the approved program. Except as
provided by section 25-8-205.5, control regulations related to agricultural
practices shall be promulgated only if incentive, grant, and cooperative programs
are determined by the commission to be inadequate and such regulations are
necessary to meet state law or the federal act. This subsection (5) does not allocate
wasteloads or relieve any source from participation in wasteload allocations
determined necessary under any duly promulgated regulations established by the
water quality control commission under this section.
(6) The division may issue a variance from a control regulation of general
applicability, based upon a determination that the benefits derived from meeting
the control regulation do not bear a reasonable relationship to the economic,
environmental, or energy impacts or other factors which are particular to the
applicant in complying with the control regulation; except that such variance shall
be consistent with the purposes of this article including the protection of existing
beneficial uses. No variance shall be issued for longer than five years. Variances
shall be granted or renewed according to the procedure established in section 25-8-401 (5).