On-Going Research to Estimate Groundwater Recharge in Agricultural Areas of the Mesilla Valley

Salim Bawazir1 and Alexander “Sam” Fernald2

Graduate Students: Kevin Boyko3 and Jusep Artola3

Project Collaborators: J. Phillip King1 , Zohrab Samani1, Juan Solis1+

Project Funded by the USGS-Transboundary Aquifer Assessment Program (TAAP) through NM WRRI

1 Faculty, Civil Engineering Dept., NMSU;1+ PhD candidate, Civil Engineering Dept., NMSU2 Faculty Watershed Management and Director of NM Water Resources Research Institute3 Water Science and Management Program, NMSU

Background

• Mesilla Valley Aquifer (Mesilla Bolson) is a trans-boundary aquifer shared between New Mexico, Texas and Mexico

• Significant portion of the drinking water supply for the City of El Paso and Juarez

• Main source of drinking water for residents of Mesilla Valley

• Main source of irrigation water during dry years

• The aquifer is vital for the sustainability of the agricultural industry, economic development and the quality of life in Southern New Mexico, El Paso, and Juarez

• The long-term management and sustainability of the Aquifer depend on understanding the dynamic of the aquifer

Project Objectives:

- Measure Evapotranspiration (ET) of one of the major crops (i.e. Alfalfa) in the Mesilla Valley

- Measure ET of fallow farm field- ET of fallow ground has not been well quantified in

the hydrologic budget; Often considered “miniscule” and therefore considered “zero”

- Use Ground level ET measurements to verify remote sensing ET Models [Mesilla Valley ET]

- Estimate groundwater recharge based on irrigation practices

Upper (Top) Boundary Layer (i.e. ET) of Groundwater model has often been assumed

MeasurementLocations

Salopek: 84 acres (34 ha)

Willies: 87 acres (35.2 ha)

Leyendecker Climate Station(NMSU: Leyendecker Plant Science Station)

Willies Farm – Alfalfa (Eddy Covariance System and Climate Station)

Eddy Covariance System

Climate Station

Soil Moisture Profile

Depth to Groundwater

Salopek Fallow Farmland –Alfalfa (Eddy Covariance System and Climate Station)

Preliminary Results:

Recharge to Groundwater: 1.0 - 1.5 ft

ET of alfalfa = 4.6 ft (1403 mm)

Precipitation = 11 in or 0.92 ft (277 mm)

Irrigation Applied = 5.67 ft (1729 mm)

N= 271 days of data collection

Willie’s Farm; Measured ET Values and Remote Sensing REEM ET Estimates

2/25/2017 Measured = 2.03 mm REEM Satellite Model = 2.00 mm (avg.)3/13/2017 Measured = 4.9 mm REEM Satellite Model = 4.00 mm (avg.)

Improving Remote Sensing ET Models (REEM and SSEBop) is in Progress for the Mesilla Valley

2/25/2017

Remote Sensing Model Estimates –Sample of REEM Estimates

Thank you