Located on a parcel of land directly across from Santa Rita Park, the Durango Pumping Plant will lift water from the Animas River up through the Ridges Basin Inlet Conduit into Lake Nighthorse. The pumping plant will be placed about 200 feet from the river and will include: an intake structure, a service yard, and a surge chamber.
The intake structure will take water from the river through control gates to the pumping plant. A fish by-pass structure will keep fish from entering the pumping plant and return them to the river. The pumping plant will have a total of eight pumps that will pump water from the river, in sizes ranging from 14 cubic-feet per second (cfs) to 56 cfs. Different pump sizes are needed to accommodate high and low flows in the river and provide backups in case one of the pumps is out of service.
Construction of the pumping plant will take approximately five years. The work will require the blasting and excavation of significant amounts of bedrock material below the ground surface. Blasting activities will be carefully conducted using safety monitors, warning signs, blasting mats, and protective barriers. Construction of the pumping plant intake structure and fish by-pass structure will require the placement of two temporary dams (cofferdams) around the work areas in the river. In order to minimize the size of the coffer dams and the impacts to the river, Reclamation is requiring this work be done when river flows are at their lowest. River recreation will still be able to continue during this phase of construction.
|Ridges Basin Inlet Conduit Features||Durango Pumping Plant Features|
|Capacity: 280 cubic feet per second||Overall plant length: 230 feet approx.|
|Distance: 2.1 miles||Width of plant: 65 feet approx.|
|Inlet Pipe Size: 72-inch diameter||Height of plant: 100 feet approx.|
- Downstream senior water right demands on the river
- Amount of water in the river
- Seasonal minimum by-pass flows
- Pumping capacity of the Durango Pumping Plant
- Design-based reservoir filling criteria
- Traffic flow disruption - Santa Rita Park area
- Increased air/dust pollution in Durango city limits
- Increased sediment flow in Animas River from coffer dams
- Intermittent increased noise
- Disruption of river-related recreation
Throughout the entire construction process and following completion of the Durango Pumping Plant, the safety of the public and the site workers is Reclamation's highest priority. Reclamation officials will take every precaution to ensure public safety during all construction activities. Only state-of-the-art design and construction practices to monitor, examine, and evaluate the construction of the Durango Pumping Plant will be used. Reclamation will ensure that noise levels from the construction work are within acceptable limits.
The Ridges Basin inlet conduit (pipeline) is approximately 2.1 miles in length and consists of a 72-inch diamater steel pipe that will carry Animas River project water from the Durango Pumping Plant to Ridges Basin Reservoir. The route of the conduit from the pumping plant to the reservoir travels southerly from the pumping plant, turns southwest to cross CR 211, and then turns up Bodo Draw and crosses alongside CR 211. The conduit route from the Animas River up Bodo Draw to Ridges Basin was selected because it provides the lowest pumping lift between the river and Ridges Basin Reservoir.
The conduit will be buried in a trench at a normal depth of five to eight feet below the ground and backfilled so that upon completion of the construction, the terrain can be returned to natural contours and vegetation. Construction of the protective sleeve for routing natural gas pipelines over the reservoir conduit was completed in October 2002. Three natural gas pipelines will be re-routed over the inlet conduit sleeve in the spring of 2003.
Upon completion of the entire project, water stored in Lake Nighthorse will be released from the dam as necessary and will fall via gravity back to the Animas River for use by municipal and industrial users within Colorado and New Mexico. Lake Nighthorse will impound approximately 120,000 acre-feet (AF) of water and include an inactive pool of approximately 30,000 AF for recreational, fishery, and water quality purposes.