PROJ01937 (2) - Laserfiche WebLink

Home Browse Search

Executive Summary The purpose of this study is to supplement the original feasibility study completed by Smith Geotechnical entitled "Feasibility Study for Construction of Dry Creek Reservoir" dated January 2003. Since the completion of this initial study, the project sponsors determined that it is necessary to design and construct a larger reservoir than that originally planned. This supplemental study will detail the reasons for constructing a larger reservoir and discuss the differences between the selected alternative in the original study and the proposed facilities. The layout of this study will minrorthat of the original study to allow for comparison between the two documents. Where appropriate, this study will refer to the original study. The project will be funded by the Little Thompson Water District (LTWD) and the Central Weld County Water District (CWCWD), together referred to as the Districts. Both Districts are requesting additional funding through the Colorado Water Conservation Board (CWCB) for their respecti ve portions of the project. The study has been prepared in conformance with requirements for funding of the CWCB and the dam safety regulations of the Colorado State Engineer's Office (SEa). The proposed project includes the construction of an earthfill embankment, roller-compacted- concrete (RCC) spillway section, and low-level outlet. The low-level outlet will be constructed as a bi-directional conduit through the dam. The outlet will be used to evacuate the reservoir during emergencies and to fill the reservoir from the St. Vrain Canal, located above the Carter Lake Filter Plant. Reservoir withdrawals will also be made from the reservoir outlet via a pump station and pipeline to the Carter Lake Filter Plant. The key differences between the selected alternative in the original study (small reservoir) and the proposed facilities (large reservoir) include the following: ~ Increase in reservoir capacity from 5,200 acre-feet to 8,850 acre-feet, which results in a increase in dam height from 42 to 55 feet and increase in crest length from 2,610 to 4,820 feet; Dry Creek Reservoir Project 11l ElClVLE