Water Use and Conservation Potential for Domestic Wells in the Espaņola Basin

Results of a Bureau of Reclamation and the Española Basin Regional Issues Forum–funded GIS-based water resource inventory of the Española Basin reveals the actual water use by domestic wells and the potential for water savings. Self-supplied domestic wells are wells serving one to several households permitted under New Mexico Statute 72-12-1. Approximately 8200 wells are permitted and contain information in OSE WATERS database in the Española Basin. Of these wells, about 500 wells are metered and about 70 of the wells identify the specific houses served. Based on our analysis of the meter records, annual water pumping ranges from 0.03 to 1.6 acre-feet per year (ac-ft/yr) per house with a median of 0.26 ac-ft/yr per home. Using the 2010 census for the average household size per block group to estimate the population for each house, the median per capita demand is 0.12 ac-ft/yr (110 gallons per capita per day). The total estimated diversion from the self-supplied wells is 5700 ac-ft/yr or 22% of the total diversions in the region for municipal, commercial, and residential uses. The amount of water that would be needed for each of these homes was estimated by digitizing the landscaping using aerial photography and calculating water needed for a conserving and non-conserving household. The results showed that if conservation techniques were applied (inside and out) and buffalo grass were used for the same area of landscaping, the water use would be 0.07 ac-ft/yr per person, and if non-conserving techniques were applied the median use would be 0.17 ac-ft/yr. An estimated 43,000 people are supplied by domestic wells in the Española Basin, thus with an average savings of 0.05 ac-ft/yr per person, savings for this water sector could be about 1900 ac-ft/yr or 7.5% of the total M&I diversions for the region.