62 nd Annual New Mexico Water Conference

Transcription

1 62 nd Annual New Mexico Water Conference Kenneth (KC) Carroll Plant & Environmental Science Department and Water Science & Management Program

2 Brackish Groundwater Source for Desalination Water resources are becoming more limited and threatened by both anthropogenic (e.g., transboundary political/legal issues) and natural (e.g., long-term drought) issues. Approximately 15-billion acre-feet may be available of saline groundwater in New Mexico aquifers (Hale et al. 1965; USBR 1976). It is estimated that the Mesilla Bolson Aquifer contains on the order of 50 million acre-feet of fresh to brackish water. A binational (US/Mexico) desalination plant could be developed in the Santa Teresa area that would draw brackish water from a well field in the Mesilla Aquifer in both countries. Brackish has not been extensively used in NM previously, and represents a new water source.

3 Brackish Groundwater Source for Desalination We need to evaluate the impacts of using brackish source water and concentrate disposal on fresh groundwater and surface water resources. Uncertainty still exists in salinity spatial distributions, brackish water extraction feasibility, and sustainability of desal source water. We do not know how much recharge, flow, mixing, and salinity transfer occurs in and between the fresh and brackish groundwater zones. We do not know how sustainable our fresh and brackish water resources are, because we have not characterized the recharge, storage, flow dynamics, and resiliency of the groundwater system, especially for the brackish zones. We have not evaluated the potential impacts this will have on the hydrologic system (e.g., drawing fresh water into saline formations, land subsidence, surface water declines).

4 Surface Water Capture Texas v. New Mexico (Docket No Supreme Court filed with the Special Master) Diversion/Conveyance Canal Irrigation Crop Water Use Seepage Groundwater Well Field Drainage Drain Return Flow Rio Grande (Slide Credit: Phil King, NMSU)

5 Sea Water Intrusion (Modified from U.S. Geological Survey, 1984, National water summary Hydrologic events and issues: U.S. Geological Survey Water-Supply Paper 2250)

6 Credit: Land Subsidence

7 Desalination Concentrate Management

8 Recent and Relevant USGS Publications

9 Statewide Collaboration Evaluating Water Balance Components Collaboration Efforts Remotely Sensed Evapotranspiration and Precipitation Assessment Oil and Gas Produced Water Assessment Statewide Systems Dynamics Water Budget Groundwater Recharge Assessment Groundwater Level and Storage Changes Surface Water Flow Statistics Water Use Reporting

10 NM-WRRI Riparian Evaluation Deep Groundwater Age Dating Evapotranspiration Modeling Evapotranspiration Measurement NM-USGS Rio Grande Transboundary Integrated Hydrologic Model Mesilla Basin Monitoring Network (Deep Groundwater Age Dating) Geothermal modeling

11 NMSU and US BoR Cooperative Agreement Manoj Shukla, Plant and Environmental Sciences Department, College of Agricultural, Consumer and Environmental Sciences (ACES), Irrigation with Brackish Groundwater and Desalination Concentrate: Effect on soil microbial properties, plant uptake and ion deposition in soil Tanner Schaub, Chemical Analysis and Instrumentation Laboratory, College of ACES, Advanced Chemical Analysis Capability for Alternative Water Source Research Sarada Kuravi, Department of Mechanical and Aerospace Engineering, College of Engineering, Low Cost, Low Energy Concentrate Water Desalination using Heat Recuperative Solar Still with Concentrating Solar Technology J. Phillip King, Department of Civil Engineering, College of Engineering, Assessment of Brackish Groundwater Desalination for Municipal and Industrial Water Supply in Santa Teresa, New Mexico Brian Hurd, Department of Ag Econ & Ag Bus, College of ACES, Valuing the Potential Contribution of Desalination and Water Reuse to the Water Supply Portfolio of Southern Dona Ana County, New Mexico Kenneth C. Carroll, Plant and Environmental Sciences Department, College of ACES, Isotopic, Geochemical, and Modeling Evaluation of Source Water, Extraction Potential, and Potential Impacts of Using Brackish Water for Desalination in the Mesilla Basin, NM

12 Assessment of Brackish Groundwater Desalination for Municipal and Industrial Water Supply in Santa Teresa, New Mexico Project objective: Investigate the hydrogeologic, technical and economic potential for desalinating brackish groundwater in the Santa Teresa-San Jeronimo area Conduct a proof-of-concept demonstration with a pilot desalination plant and existing brackish wells Develop an organizational and financial plan for moving forward with desalination implementation

13 Assessment of Brackish Groundwater Desalination for Municipal and Industrial Water Supply in Santa Teresa, New Mexico Working with local entities to assess water demand, current supply, and binational potential Developed dialog with Universidad Autónoma de Chihuahua s Department of Civil Engineering colleagues as project collaborators Conducted water chemistry analyses for local water samples found elevated As, Na, TDS, high spatial variability Acquired pilot-scale test units from NMSU Testing pilot-scale desalination system using reverse osmosis (RO) and nanofiltration (NF) membranes Initial stakeholder meeting, including UACH, scheduled for August 4, 2017

14 Valuing the Potential Contribution of Desalination and Water Reuse to the Water Supply Portfolio of Southern Dona Ana County, New Mexico Conceptual Approach linking Groundwater, Communities, and Environment Characterize Plausible Future Conditions Climate Change Identify and apply representative climate change scenarios ( dry, middle, wet in 2 time periods, 2030s and 2080s ). Population Growth Develop a baseline demographic change scenario that estimates changes in population, incomes and urban water demand. Simulate Hydrologic and Economic Processes Streamflow Change A simplified lumped water balance model (WATBAL) is used to project changes in streamflows, irrigation requirements, and evaporation losses. Groundwater Management Alternative aquifer management scenarios are used to examine effects on the value of water. Water Use and Economic Impacts A hydro-economic water management model of the Upper Rio Grande watershed (RioGEM) optimizes the economic value of water use across the entire watershed.

15 Isotopic, Geochemical, and Modeling Evaluation Sampling of dissolved noble gas isotopes from groundwater

16 Isotopic, Geochemical, and Modeling Evaluation Dissolved noble gas isotopes to supplement traditional age dating fills a middle age range gap.

17 Brief Summary Brackish may be developed to support water resources in NM. Desalination source water sustainability likely still has significant uncertainty. Brackish water development for desalination should also include evaluation of potential impacts. Some work has been ongoing, but more needs to be done.

18 Acknowledgements This work has been supported by: NMSU Ag. Experiment Station & USDA Southwest Hub for Risk Adaptation and Mitigation to Climate Change The Statewide Water Assessment funded by NM State through the Water Resources Research Institute The U.S.-Mexico Transboundary Aquifer Assessment Act (Public Law ) The U.S. Bureau of Reclamation cooperative agreement with NMSU The U.S. Geological Survey especially from Andrew Robertson

19 Thank you Any questions?

20 Mesilla Basin Groundwater Sampling and Modeling Groundwater samples are being collected for chemical and isotopic analyses, and the results will be modeled to evaluate brackish groundwater production.