BOARD00363 - Laserfiche WebLink

Home Browse Search

Artificial Recharge of Ground Water in Colorado A Statewide Assessment Other Colorado Recharge Operations A number of smaller AR applications throughout the state are shown in Figure VI-]. These include sites where AR is used to modify water quality, provide short-term water volume regulation, and provide augmentation water. Moulder and others (1963) described eight community water systems that used AR to both pretreat surface-water quality and regulate unreliable surface-water volumes. These small AR applications capture surface water that is prone to detrimental water quality conditions, such as high turbidity during spring runoff or flooding, as well as highly variable flow rates. These sites consist of a surface diversion combined with some type of surface infiltration structure. Ground water is then withdrawn down gradient for use in the system. In some instances, the AR application has been specifically designed as a pretreatment facility. For example, Salida (CSL-l in Figure VI-2) diverts water from the South Arkansas River into two infiltration ponds. A horizontal perforated pipe beneath the ponds extracts the clarified water for use when river flow is low. Other applications are more accidental, taking advantage ofleaky reservoirs. Although leaky reservoirs may not strictly meet the definition of AR, they are included in this inventory because of their previous citation in the literature (Moulder and others, 1963). An example of this type of application is at Ridgway (CRD-l in Figure VI-2), where water is diverted into a reservoir that leaks. The town captures seepage from the drainage topographically below the reservoir. As described by Moulder, the seepage is of better quality and more reliable in quantity than the surface supply. The eight systems described by Moulder and others (1963) are Salida, Indian Hills, Littleton, Nederland, Pagosa Springs, Palisade, Ridgway, and Wheatridge Mutual. These communities were contacted as part of this inventory to determine which still utilize AR. Those that continue to use AR as described by Moulder include Salida, Indian Hills, Palisade, and Ridgway (CSL-1, CIH-l, CPD-I, and CRD-l in Figure VI-2). At the other locations modifications to the water supply systems, such as high-volume filtration units, have apparently replaced the AR applications. In addition to the eight communities described by Moulder, this investigation identified other projects where AR was used for water-quality modification or water-supply regulation. These sites, also shown in Figure VI-I, include AR by Coors Brewing Company near Clear Creek in Jefferson County (CRS-l in Figure VI-2), AR by Keystone Resorts near the Snake River in Summit County (CNT-l in Figure VI-2), and AR at several small capacity wells near the Animas River in La Plata County (CAS-l in Figure VI-2) as well as near the East Mancos River in Montezuma County (CGR-l in Figure VI-2). There are also several small-scale sites shown on Figure Vl-l (CUO-l, CPG-l, and CTC-I) where AR is used as part of augmentation plans. These consist primarily of gravel pit operations that use AR to replace ground water lost to evaporation. Lastly, the City of Arvada has started using the abandoned Leyden coal mine (CL Y I) as an underground water storage facility by injecting treated municipal water. This mine had previously been used as a gas storage facility, and is estimated to have a 3,000 ac- ft water capacity. Inactive Artificial Rechan!:e Operations The inactive category includes projects that are still in the planning stages, pilot projects reported in the literature that have not led to full-scale AR implementation, as well as AR operations that 48