Estimating Evaporative Losses Incurred by Conveyance of City of Albuquerque San Juan-Chama Water: Jemez to Albuquerque

Science Center Objects

The City of Albuquerque is in the process of implementing the Drinking Water Project, which is part of the Albuquerque Water Resources Management Strategy. As part of this strategy, the City will begin accepting delivery of imported San Juan-Chama water to supplement present municipal water supplies. The City of Albuquerque’s annual allotment of imported San Juan-Chama water is 48,200 acre-feet/year, which is to be delivered from Heron Reservoir. The City may only use the portion of its San Juan-Chama water that remains after evaporative losses have been accounted for. Evaporative loss factors for delivery of the City’s San Juan-Chama water in the Jemez-to-Alameda Bridge reach of the Rio Grande have not been approved by the Rio Grand Compact Commission.

Evaporative loss factors for San Juan-Chama water that is to be delivered to points between Heron Reservoir and the mouth of Jemez River have been previously determined; these evaporative loss factors have been agreed upon by the Rio Grande Compact Commission and the US Bureau of Reclamation (1974); Martin (1996); CH2MHill (2002).

Objectives and Scope

The objective of this project is to determine evaporative losses incurred by conveyance of City of Albuquerque San Juan-Chama water from the mouth of the Jemez River to the point of diversion (Alameda Bridge), under various streamflow conditions. The width-discharge relation of the Jemez-to-Alameda Bridge reach of the Rio Grande will be approximated for the appropriate range of discharge. This relation, in addition to measured evaporation rates (Rio Grande Compact Commission, 2001, p. 66), will be used to estimate the evaporative losses of the City’s San Juan-Chama water between the mouth of the Jemez River and the Drinking Water Project (DWP) point of diversion.



This study will be approached in two general phases: data collection and data interpretation.


Phase I

The reach of the Rio Grande between the mouth of the Jemez River and the DWP point of diversion will be divided into reaches of similar physical and geomorphic characteristics. The appropriate range of discharge will be determined based on (1) the minimum flow of the Rio Grande, below which the City will not divert water, and (2) the maximum threshold flow, above which there is no increase in width with increases in discharge.

For each reach, width-discharge relations will be developed for various streamflow conditions within the appropriate range of discharge. Aerial photographs, which are available for a range of streamflow conditions, will be used to determine the width of open water, wetted and dry sand at 10 or more transects for each reach. An existing wetland database, which defines the perennial channel, seasonally flooded areas, and islands, may be used to supplement data collected from aerial photographs. Additionally, channel cross-section data collected by the USGS, US Bureau of Reclamation (USBR), and US Army Corps of Engineers (USACE), will be used in developing width-discharge relations.


Phase II

Monthly evaporative-loss calculations will be made for the previously determined ranges of discharge. The calculations will be a function (1) total discharge in the channel, and (2) percentage of City of San Juan-Chama water in the channel. Assumptions include (1) seepage and transpiration losses are not a function of San Juan-Chama water and, therefore, can be neglected, and (2) channel morphology, which governs the width/discharge relation, does not substantially change over time.



Blanchard, P. J., 1993, Ground-water-level fluctuations in the Cochiti Dam-Pena Blanca area, Sandoval County, New Mexico, 1976-89, U.S. Geological Survey Water-Resources Investigations Report 92-4193, 72p.

Bureau of Reclamation, 1974, Proposed methods for computing channel losses: San Juan-Chama Project Water Accounting: U.S. Bureau of Reclamation document, 8/6/1974.

Bureau of Reclamation, 1985, San Juan-Chama Project incremental channel loss study between Cochiti Dam and Elephant Butte Reservoir, 41p.

Byrd, D., Allen, H.R., and Montaño, M., 2003, Water resources data New Mexico water year 2003, U.S. Geological Survey Water-Data Report NM-03-1

CH2MHill, 2002, Analysis of SJM Water Loss Factors for OSE Hearing on Permit 4830: CH2MHill Technical memorandum, Albuquerque, New Mexico, 10/04/02, 8 p. plus 1 attachment.

City of Albuquerque Public Works Department, 1997, City of Albuquerque Water Resources Management Strategy: Evaluation of Alternatives and Strategy Formulation, 47 p.

Farnsworth, R.K., E.S. Thompson, and E.L. Peck (1982). "Evaporation Atlas for the Contiguous 48 United States," NOAA Technical Report NWS 33, Washington, D.C.

Gold, Robert, 1985, Potential incremental seepage losses in an alluvial channel in the Rio Grande Basin, New Mexico, U.S. Geological Survey Water-Resources Investigations Report 84-4268, 22p.

Lewis, A., 2001, "The Buckman Well Field" in Johnson, Peggy S. (editor) Water, Watersheds and Land Use in New Mexico: Impacts of Population Growth on Natural Resources. New Mexico Decision Makers Field Guide No. 1., New Mexico Bureau of Mines and Mineral Resources. Albuquerque, New Mexico, p. 27

Martin, Karl, U.S. Bureau of Reclamation, 1996, Supporting documentation for SJ-C loss rates: memorandum to Gary Daves and Norm Gaume, COA, and Bill Miller, ISC: 10/10/1996.

McAda, D. P., 1988, Simulation of the Regional Geohydrology of the Tesuque Aquifer System near Santa Fe, New Mexico, U.S. Geological Survey Water-Resources Investigations Report 87-4056.

McAda, D. P. and Barroll, Peggy, 2002, Simulation of ground-water flow in the Middle Rio Grande Basin between Cochiti and San Acicia, New Mexico, US Geological Survey Water-Resources Investigations Report 02-4200, 81 p.

McAda, D. P., 1990, Simulation of the effects of ground-water withdrawal from a well field adjacent to the Rio Grande, Santa Fe County, New Mexico, US Geological Survey Water-Resources Investigations Report 81-4184, 27 p.

McDonald, M.G. and Harbaugh, A.W., 1988, A modular three-dimensional finite-difference ground-water flow model: U.S. Geological Survey Techniques of Water-Resources Investigations, book 6, chap. A1, 586 p.

Rio Grande Compact Commission, 2001, Report of the Rio Grande Compact Commission 2000, 68 p.

Tetra Tech, Inc. 2004. Development of the Middle Rio Grande FLO-2D flood routing model, Cochiti Dam to Elephant Butte Reservoir, Surface Water Group, Albuquerque, New Mexico. Prepared for the Bosque Initiative Group, U.S. Fish and Wildlife Service and the U.S. Army Corps of Engineers.

USGS, 1977, Water resources data for New Mexico water year 1976, U.S. Geological Survey Water-Data Report NM-76-1,

Veenhuis, J.E., 2002, Summary of flow loss between selected cross sections on the Rio Grande in and near Albuquerque, New Mexico, US Geological Survey Water-Resources Investigations Report 02-4131, 30 p.