Water Supply and Demand Study 1/13/11

Section 2
A -LP Project Water Supply and
Updated Costs
This section fully describes the physical availability and cost of the State Water and any restrictions that
may be involved with delivering this water for municipal use. Refining capital repayment and estimated
OM &R costs is required to allow marketing of the State Water. Brown and Caldwell conducted the
following tasks to more closely define the capital payment due to Reclamation and clarify the
components of OM &R and the payments of such required by the Association.
All of the capital costs have been developed by Reclamation. The State will negotiate capital costs
during development of repayment contract.
2.1 Availability of Water from Lake Nighthorse
The A -LP Project underwent many transformations prior to its construction and is now composed of the
following structures to serve municipal and industrial (M &I) users within Colorado and New Mexico.
• Ridges Basin Dam: The dam is a 217 feet high, 1,670 feet long earth - filled structure.
• Durango Pumping Plant (DPP): The DPP is located across the Animas River from Santa Rita Park in
Durango, Colorado, and has a total pumping capacity of 280 cubic feet per second (cfs). The DPP
has eight pumps ranging from 14 cfs to 56 cfs in size. The DPP, about 200 feet from the Animas
River, will lift water from the Animas River up through the Ridges Basin Inlet Conduit 511 feet into
Lake Nighthorse.
• The Ridges Basin Inlet Conduit: The inlet pipeline, approximately 2.1 miles long and 72- inches in
diameter. The steel pipeline will carry Animas River water from the DPP to Lake Nighthorse.
• Lake Nighthorse: The lake can physically store up to 120,000 AF of water, 30,000 AF of which is
inactive. Reclamation began filling Lake Nighthorse in April 2009. By August 2010 it had in storage
an estimated 72,000 AF, a combination of pumping from the Animas River, flows from Basin Creek
and precipitation events. The Lake is estimated to fill by summer 2011. At capacity, the Lake will
have a surface area of 1,460 acres.
• Navajo Pipeline. The pipeline is located downstream along the San Juan River. It is approximately 30
miles long and will deliver water from Fruitland to Shiprock, New Mexico and the Navajo Nation.
Land west of Durango, predominately in the La Plata River Basin, may receive A -LP Project water for a
domestic water system. The use of this water, however, will require construction of various water
conveyance components (i.e. pumps, conduits, etc.), which to -date have not been designed or
constructed. In order to facilitate delivery of water in the future from the reservoir, an intake tower was
constructed, under the direction of the La Plata West Water Authority, funded in part by a $1.1 million
grant from the CWCB.
Water Availability
The primary source of water for Lake Nighthorse is the Animas River. Flows in the Animas River are
highly variable, with most water coming from spring runoff, peaking in June. The average annual runoff
2 -1
FINAL ALP Report_1_13_11_LL.Docx