2011-05-18_HYDROLOGY - M1979191 - Laserfiche WebLink

Home Browse Search

Mr. Jared Dains May 17, 2011 Middle Poudre Combined Plan - Lafarge West, Inc. Page 6 of 9 is attached to this letter. The source of the replacement water will be from Gray Lakes, which can deliver water to Box Elder Creek and from there to the Cache La Poudre River. Approximately 1.1 acre-feet 'of water (0.25 percent per stream mile) from the Gray Lakes are estimated to be required to replace transit losses. The water storage right for the Gray Lakes owned by LCRC is not presently decreed for augmentation, therefore a change of use application for the Gray Lakes water storage right was filed with the Division 1 Water Court in case no. 2006CW276. A detailed historical consumptive use analysis was performed by TZA Water. Engineers, Inc. (`TZA") in support for case no. 2006CW276. According to the analysis LCRC water rights have historically been used to provide supplemental water to irrigated lands within the Lake Canal Service area. Based upon the crop mix, irrigated acreage and water available for irrigation, TZA concluded that the Lake Canal system is water short. TZA also noted that a historical consumptive use of 65% is not uncommon for the use of supplemental reservoir water within water short ditch systems. For the purposes of this plan, the consumptive use associated with the Gray Lakes water was assumed to be 45%. This also means 55% of the delivered water constituted historical return flows, which must be maintained. Therefore, in addition to the 12.20 acre-feet of water to be released for replacement purposes, an additional 13.6 acre-feet (for a total storage release of 25.8 acre- feet) representing the return flow component shall be release from Gray Lakes to maintain the historical return flow regime. In accordance with the letter dated April 30, 2010 (copy attached) from the Colorado Division of Reclamation, Mining, and Safety ("DRMS"), all sand and gravel mining operators must comply with the requirements of the Colorado Reclamation Act and the Mineral Rules and Regulations for the protection of water resources. The April 30, 2010 letter from DRMS requires that you provide information to DRMS to demonstrate you can replace long term injurious stream depletions that result from mining related exposure of ground water. The.DRMS letter identifies four approaches to satisfy this requirement. The 4th approach requires documentation to identify what water rights or other permanent water source will be dedicated to the SWSP to assure that all permanent depletions from either an unforeseen abandonment of the site by the. Applicant or as a result of long term ground water exposure after dompletion of mining and reclamation will be replaced so as to prevent injury to other water rights In accordance with approach no. 4, you have provided an affidavit dated November 22, 2010 that dedicates 8.5 Box Elder Ditch shares water as replacement water solely for this SWSP for as long as there are depletions at this gravel pit sites or until such time as another replacement source is obtained. A copy of the affidavit is attached to this letter. For the purposes of this SWSP, this affidavit will be accepted for the dedication of the shares; however, if the State Engineer determines that a different affidavit or dedication process is necessary to assure proper dedication of the shares, additional information may be required prior to future SWSP approvals. A monthly breakdown of the stream depletions from the mining operations as well as the replacements is shown in the attached Table 1. Conditions of Approval I hereby approve the proposed substitute water supply plan in accordance with Section § 37-90- 137(11), C.R.S. subject to the following conditions: 1. This plan is approved with an effective date of November 1, 2010 and shall be valid through December 31, 2011 unless otherwise revoked or modified. If this plan will not be made absolute by a