Reservoir Operational Models
Initially, a reservoir operational model had to be developed to demonstrate purpose and need related to obtaining a section 404 permit for the reservoir. Subsequently, after the reservoir had been permitted and built, LWS has conducted numerous operational studies to evaluate the most efficient use of reservoir storage, given the District’s diverse water rights portfolio, including both current Cherry Creek and Newlin Gulch surface water supplies as well as alluvial aquifer water, and Denver Basin aquifer water. LWS has also conducted operational studies to evaluate a projected trans-basin diversion from its Logan County Farms.
Fort Knox Water Supply Reservoir:
The Fort Knox Gold Project proposed to process approximate 35,000 tons per day of ore material and needed a large water supply for the mill. LWS personnel developed a reservoir operational model to assess the water supply availability on Solo and Last Chance Creeks relative to building a water supply dam and reservoir downstream of the confluence of the two creeks. Complicating factors in the reservoir operational model were the extreme cold conditions in north-central Alaska (north of Fairbanks), which results in several feet of ice on a reservoir over an approximate 9-month period, and the presence of permafrost on the north-facing slopes which were expected to thaw once the reservoir filled. The results of the reservoir operational study indicated a sufficient water supply could be provided for the mill, even with the complicating factors and the reservoir was built and has been providing a water supply to the mill.
Orlando and Cucharas Reservoirs:
Orlando Reservoir is an off-stream reservoir located on the Huerfano River, while the Cucharas Reservoir is an on-stream reservoir on the Cucharas River. Both reservoirs are currently adjudicated for irrigation use and reservoir operational model studies have been conducted to assess the future yields from these reservoirs, both for continued irrigation use and for potentially adjudicating a change of use in Water Court. The results of the reservoir operational model studies have helped guide the client with decisions regarding future use of the reservoirs.
Timnath Landing Augmentation Pond:
A residential and commercial development is proposed in Timnath, Colorado and the property is adjacent to the Poudre River and overlies an ancient buried channel of Box Elder Creek. Because of the local geology, a permanent dewatering system had to be designed to allow the residential and commercial development on the property. Water from the Lake Canal is to be used for augmentation of depletions associated with the dewatering operation. A reservoir operational model was conducted to evaluate the on-site storage capacity that would be necessary to manage the changed Lake Canal share water to provide a reliable augmentation supply. The results of the reservoir operational model have assisted the client with evaluating its options relative to the source of its overall augmentation supply.