2 CCR 402-8-6 - IMPLEMENTATION OF STANDARDS AND CLASSIFICATIONS FOR NONDECREED EXCHANGES AND SUBSTITUTE SUPPLY PLANS

6.1 Pursuant to C.R.S. 37-80-120(3), the State Engineer has the authority, in reviewing applications for approval of nondecreed exchanges and substitute supply plans, to require that the substitute supply shall be of a quality to meet the requirements of use to which the senior appropriation receiving the substituted supply has normally been put.

6.2 Pursuant to C.R.S. 37-80-120(3), the State Engineer shall determine whether the substitute supply is of a quality to meet the requirements of use to which the senior appropriation has normally been put.

6.3 The State Engineer may reasonably require the applicant to provide water quality data and analysis or other information to properly evaluate and analyze the quality of the substitute supply and assure the requirements of use of the senior appropriator are met. If such water quality data and analysis or other information requested by the State Engineer is not provided within 30 days of request, or an extension of time thereof, the nondecreed exchange or substitute supply plan shall be denied. Denial shall not impair the timely evaluation of a resubmitted request for a nondecreed exchange or substitute supply plan with the requested data.

6.4 In the evaluation and analysis of the quality of the substitute supply and in implementing the provisions of Rule 3.6, the State Engineer may require and utilize some or all of the following information and criteria or other criteria and information deemed appropriate:

6.4.0 Evaluation of engineering reports, data, and other information provided by the applicant.

6.4.1 Investigation and evaluation of the use to which the senior appropriation has normally been put.

6.4.2 Information and records from Water Division Engineers, Water Commissioners, and downstream vested water users.

6.4.3 Evaluation of water quality data of the substitute supply or the receiving waters at or near the point where the substitute supply enters the waterway or aquifer.

6.5 In the evaluation and analysis of the quality of the substitute supply and in determining whether to grant or deny a proposed nondecreed exchange or substitute supply plan, the State Engineer shall apply the following provisions:

6.5.0 Pursuant to C.R.S. 37-80-120(3), the substituted water shall be of a quality to meet the requirements of use to which the senior appropriation receiving the substituted supply has normally been put.

6.5.1 Nondecreed exchanges and substitute supply plans reviewed by the State Engineer, which do not meet the requirements of use to the senior appropriator, are subject to denial by the State Engineer.

6.5.2 If appropriate water quality standards and/or classifications have been established by the Water Quality Control Commission, they shall be considered in determining water requirements of senior appropriators and the State Engineer shall consider the water quality standards for the use which is appropriate to the senior appropriator. For example, if the senior beneficial use is agricultural in nature, then the appropriate standards for agricultural use may be applied, if such criteria have some factual correlation to the particular use of the senior appropriator.

A mass balance analysis or mixing zone approach may be used to determine if the water quality standards are met for the senior appropriator's use.

6.5.3 The State Engineer shall consider water quality standards and classifications only if the Water Quality Control Commission has established standards and/or classifications for the beneficial use in question.

6.5.4 If as a result of the evaluation and analysis of the quality of the proposed substitute supply pursuant to Rule 6, the State Engineer finds the requirements of use of the senior appropriator have been met, but the quality of the substitute supply fails to meet water quality standards, the State Engineer shall approve the nondecreed exchange or substitute supply plan if other statutory requirements of C.R.S. 37-80-120 are met. Notification of such an approval shall be reported to the Water Quality Control Commission and where appropriate the Department of Agriculture.

6.5.5 Substitute supply plans approved by the State Engineer, prior to the effective date of these rules, shall be presumed to meet water quality standards, however, upon request for renewal, the substitute supply plan shall be re-evaluated to assure the substitute supply meets the requirements of use of the senior appropriator receiving the substituted supply.

6.5.6 The State Engineer shall, under normal circumstances, consider proof of the following substitute supplies as evidence that the requirements of use to which a senior appropriation has normally been put will be met:

6.5.6.1 Water discharged to surface streams in compliance with either a valid state discharge permit or with the applicable water quality standards under these Rules, where the applicable stream classifications include all uses to which the senior appropriation has normally been put and the standards include all parameters necessary to protect the requirements of use of the senior appropriator;

6.5.6.2 Water supplies treated in accordance with the Safe Drinking Water Act and in compliance with the drinking water standards of the state and applied to lawns for irrigation;

6.5.6.3 Surface water left in the stream by foregoing diversion or diverted from the stream but returned from the same diversion or measuring facility without alteration of quality for use as a substitute supply.

6.5.6.4 Water from any stream or other source that is designated by the Water Quality Control Commission as "High Quality".

Notes

2 CCR 402-8-6