United States – Mexico Transboundary Aquifer Assessment Proposal By Dr. Karl Wood, Director Water Resources Research Institute New Mexico State University Las Cruces, New Mexico

Problems? Human population growth along US-Mexico border is among the highest nationally Average per capita income is far below the U.S. average Economic develop is restricted by lack of adequate water Availability of water is a key issue in the U.S. – Mexico border region Groundwater is used for all the drinking water in southern New Mexico, all of Juarez, and half of the El Paso area Groundwater is probably the only source of new water as the drought continues and new desalting technology develops

borderborder Water Resources in the New Mexico Border Region

 Mined basin with water-level drawdowns exceeding 250 feet  Sole source of water for Ciudad Juarez  Major source of water for El Paso  Quality generally <1,000 mg/L TDS, but deteriorating  Very little natural recharge  Extensive modeling in El Paso/Ciudad Juarez area  Artificial recharge program by El Paso  Water Use 2000: El Paso = 126,420 acre-feet Ciudad Juarez = 124,000 acre-feet Distrito de Riego 009 = 57,000 acre-feet Hueco Bolson

Mesilla Basin Largest rechargeable reservoir in region Southern boundary in Mexico poorly defined Connected with overlying semi-confined Alluvium aquifer Quality <1,000 mg/L TDS Use: Domestic & Supplemental to Rio Grande for Irrigation Quantity pumped = ? Quantity in storage = ~60 million af - ? Number of modeling efforts, none bi- national

Jornada del Muerto  Weak connection with Mesilla Basin  Quality <1,000 mg/L TDS in south  Limited development  Very little natural recharge ~5,000 af/y in southern area  Some modeling in southern area  Water in storage = ~100 million af  Well yields low

Interconnected group of subbasins Area = 5,140 mi 2, 4,360 in US, 770 in MX Water is storage = ~30 million af Quality 500 to 1,000 mg/L TDS in south Southern boundary poorly defined Water use: ~53,000 af/y in US Recharge ~63,000 af/y Limited modeling in Deming area, none bi-national Mimbres Basin

Hachita-Moscos Basin  Interconnected Group of subbasins  Area 1,040 mi 2, 620 in NM, 420 in MX  Water in storage ~5 million af  Recharge = 4,800 af/y  Flow from US to MX about 2,000 af/y  Quality variable with areas having 1,000 mg/L TDS  Limited development  No modeling, sparse data

 Two Interconnected subbasins  Area 925 mi 2, 921 in NM, 4 in MX  Water in storage ~5 million af  Recharge = ~5,700 af/y  Quality variable with areas having <250 mg/L TDS to 500 mg/L TDS  Water use ~4,900 af/y for mineral processing (1995)  No modeling, sparse data Playas Basin

Animas Basin  Interconnected group of four subbasins  Area 2,448 mi 2  Water in storage ~9.5 million af  Recharge = ~12,700 af/y  Quality <250 mg/L TDS  Water use ~16,500 af/y in 1995 primarily for agriculture  No modeling, limited data

How extensive are the aquifers? Which directions are the aquifers flowing? How deep are the aquifers? What is the quality of the aquifers at various depths? How fast are they declining in supply and quality? What is the long-term availability? What is the relationship between surface supplies and aquifer recharge? Many questions concerning the aquifers remain:

a. Develop high-quality, comprehensive, binational groundwater quantity and quality databases Solution: A Congressionally funded initiative to d. Develop and improve groundwater flow models for bi-national aquifers to facilitate regional water assessment and planning b. Assess movement and interaction of water resources c. Analyze trends in groundwater quality, including salinity, nutrients,toxics, and pathogens g. Apply the new data and models to evaluate strategies to enhance supplies and protect water quality e.Develop land use and land cover characterization mapping information f. Develop hydrogeologic maps of both surface and bedrock deposits

Where will the work be done? Primary emphasis will start in the southern New Mexico – west Texas - northern Chihuahua region Secondary emphasis will follow in the Arizona – Sonora and California – Baja regions

Who will do the work? Scientists from: New Mexico State University New Mexico Tech University Texas A&M University – El Paso Research Center U.S. Geological Survey – New Mexico & Texas Offices University of Arizona University of California – Riverside Sandia National Laboratory Mexican counterparts Lead agencies: New Mexico Water Resources Research Institute at New Mexico State University Texas Water Resources Research Institute at Texas A&M University

Funding? U.S. Senate Bill th Congress Introduced November 25, 2003 By U.S. Senator Jeff Bingaman $5 million each year for 10 years

Action Request? Resolution of support be sent to New Mexico’s Congressional Delegation Senator Jeff Bingaman Senator Pete Domenici Representative Steve Pearce Representative Tom Udall Representative Heather Wilson

Senator Jeff Bingaman 703 Hart Senate Office Building Washington, D.C Senator Pete Domenici 328 Hart Senate Office Building Washington, D.C Congressman Steve Pearce 1408 Longworth House Office Building Washington, D.C Congresswoman Heather Wilson 318 Cannon House Office Building Washington, D.C Congressman Tom Udall 1414 Longworth House Office Building Washington, D.C Senator John Cornyn 517 Hart Senate Office Building Washington, D.C Senator Kay Bailey Hutchison 284 Russell Senate Office Building Washington, D.C Congressman Silvestre Reyes 1527 Longworth House Office Building Washington, D.C Congressman Henry Bonilla 2458 Rayburn House Office Building Washington, D.C New Mexico Delegation Texas Delegation