By October 12, 2017, grubbing and clearing at the site of the Huerfano County Water Conservancy District (HCWCD) reservoir, the Sheep Mountain Ranch Augmentation Facility, is expected to be finished by Paul Morgan Excavating. According to Carol Dunn, HCWCD Administrator, besides grubbing and clearing the site, a drainage swale is being built to carry surface water around the cleared site and direct it toward a sediment basin and ultimately into the Huerfano River. Currently, an irrigation pipeline is being installed to get the landowner’s ditch water to the hayfields so that the project will not interfere with the irrigation. Erosion control fabric has been installed to keep any muddy water from leaving the site, and a cattle guard and more permanent entrance gate will also be installed.
Already, Huerfano County has begun mining and crushing gravel on the site. The County will mine gravel out of the site until December 2018, and it is being used along with road base on Pass Creek Road. The three stockpiles of materials – topsoil, overburden, and “spoils” (material that can’t be used to construct the pond) will be seeded to protect them from wind erosion.
Around January 1, 2019, Huerfano County will finish and move off the site, and Phase 2 will begin. In Phase 2, the pond embankment will be built from materials that have been stockpiled on the site since the beginning of Phase 1. The pond will be lined with an 18-inch thick layer of compacted clay soils which have been found at the site. Representatives of TZA Water Engineers tested the soils at the site and found that they contain enough clay/fines that HCWCD will not need to purchase and install a commercial liner for the pond to hold water. That issue was another problem with the alternate pond site, located closer to Red Wing, and will save HCWCD “a couple hundred thousand dollars,” as Dunn said.
According to John Allis, Senior Project Manager with TZA Water Engineers, the finished pond, at full level, will have “a surface area of 3.78 acres, a storage volume of 49.0 acre, feet and a maximum depth of 21.0 feet.” A water diversion structure and pump station will be installed in the Huerfano River to direct flows into the pond at the correct times when the HCWCD water right, the William Craig #7, is in priority. As part of the HCWCD regional augmentation plan, the water in the pond will be released during irrigation season through a reservoir pipeline when it is needed to augment the flow of the Huerfano River as participants in the augmentation plan use water under junior water rights. Finally, the site will be graded to its final state, reclaimed and seeded.
The water stored in the pond will be part of HCWCD’s senior #7 William Craig Ditch water right. HCWCD purchased the water right as part of its purchase of the William Craig Ranch in January, 2014 from Len and Roxie Camp. HCWCD is in the process of getting an appraisal of the Ranch in preparation for selling it.