Monitoring Network of the Ground-Water Flow System and Stream-Aquifer Relations in the Mesilla Basin, Doņa Ana County, New Mexico and El Paso County, Texas
Project Chiefs: Andrew Robertson
Cooperators: New Mexico Office of the State Engineer; Elephant Butte Irrigation District; New Mexico State University; City of Las Cruces Utilities; New Mexico Interstate Stream Commission; New Mexico Environment Department; International Boundary and Water Commission--US Section, Bureau of Reclamation
Period of Project: 1987 to present
Scientific Investigations Report 2005-5248, Description of Piezometers and Ground-Water-Quality Characteristics at Three New Sites in the Lower Mesilla Valley, Texas, and New Mexico, 2003
Open File Report 1995-0111, Selected hydrologic data for the Mesilla ground-water basin, 1987 through 1992 water years, Dona Ana County, New Mexico, and El Paso County, Texas.
The Mesilla Basin monitoring program was established in 1987, and
is conducted by the U.S. Geological Survey (USGS) in cooperation with
eight local, state, and federal agencies. Monitoring program components include
the Mesilla Basin observation well network, the Mesilla Valley hydrologic
sections, and seepage investigations at selected surface-water sites.
The Mesilla Basin monitoring program has helped document recent hydrologic
conditions and established a long-term continuous data base to permit
future quantitative evaluation of the ground-water flow system and stream-aquifer
relations. Collected data was extensively used in interpretive studies
conducted by the USGS and other agencies to better define the geohydrologic
system (selected references). Hydrologic
data collected by the monitoring program will continue to provide valuable
information towards future efforts to update, revise, and calibrate basin
models of the ground-water flow system. The monitoring program continues
to document changing hydrologic conditions and stream-aquifer relations,
and identify ground-water trends.
Historic ground-water data collection efforts within the basin were limited
to obtaining data on a nonrecurring, unsystematic basis. Previous studies
emphasized the need for a comprehensive monitoring network of the ground-water
flow system in the Mesilla Basin. A long-term monitoring program is necessary
to document ground-water conditions and stream-aquifer relations
to identify changes with time.
The objectives of this monitoring program are to document hydrologic conditions
within the Mesilla ground-water basin and establish a long-term continuous
data base to permit future quantitative evaluation of the ground-water
flow system and stream-aquifer relations. To accomplish these objectives,
data collection and maintenance of the Mesilla Basin monitoring program
will continue including the Mesilla Basin observation-well network, the
Mesilla Valley hydrologic sections, and seepage investigations at selected
surface-water sites including associated water-quality analyses.
The Mesilla Basin monitoring program will continue to document changing
hydrologic conditions and identify stream-aquifer relations by conducting
the following program elements:
- Mesilla Basin Observation-Well Network
Conduct annual ground-water-level measurements at sites in the Mesilla
Basin observation-well network. Network wells are completed in the Rio
Grande flood-plain alluvium/Santa Fe Group aquifer system, with wells
located in the Mesilla Valley and West Mesa area (fig.
1). Annual winter water-level measurements and well records are entered
into the USGS National Water Information System (NWIS)--Ground-Water Site
Inventory (GWSI) data base. Mesilla Basin network wells are web ready
with information currently available to the public on NWIS Web at URL
http://waterdata.usgs.gov/nwis (table 1.)
- Mesilla Valley Hydrologic Sections
Maintain water-level record at the Mesilla Valley hydrologic sections.
These hydrologic sections consist of a river-stage station and several
observation wells aligned perpendicular to the Rio Grande. The location
of the Las Cruces hydrologic section (A-A’), Mesquite hydrologic
section (B-B’), and Cañutillo well-field hydrologic section
(C-C’) are shown on figure 1. Diagrams
of the Las Cruces, Mesquite,
and Caņutillo well-field hydrologic sections
show well completion depths and distances from the Rio Grande. The hydrologic
sections currently consist of 43 sites; 3 river-stage stations and 40
observation wells. Continuous water-level records are currently maintained
at 17 sites, with monthly water-level measurements at 36 observation wells.
Continuous water-level records are stored in the USGS NWIS--Automated
Data Processing System (ADAPS) data base and monthly water-level measurements
are entered into the GWSI data base. Real-time ground-water data collection platforms (DCP) were installed at the Las Cruces hydrologic section in observation well group LC-2 and observation well group LC-3. Well group LC-2 is located approximately 350 feet from the Rio Grande. Real-time ground-water
data are available to the public on NWIS Web at URL http://waterdata.usgs.gov/nm/nwis.
- Seepage Investigations
Seepage investigations were conducted on the Rio Grande from Radium Springs,
New Mexico, to El Paso, Texas during water years 1988 through 1998. Seepage
investigations of selected irrigation drains including associated water-quality
analyses were initiated in the 1999 water year. One irrigation drain will
be selected for investigation each water year. Biannual seepage investigations
of the selected drain will be conducted at low flow during the nonirrigation
season and at high flow during the irrigation season. Discharge measurements
will be conducted at selected sites to determine seepage gain/loss from
specific channel reaches. Water-quality samples will be collected at approximately
four main-stem sites for chemical analyses to determine dissolved solids
(salinity), and concentrations of major ions and selected nutrients. Recent
drought conditions and decreasing reservoir storage has resulted in a
significant reduction in surface-water allocations since the 2003 irrigation season, with a significant increase in ground-water withdrawals
to meet water demand. Annual seepage investigations will shift from selected
irrigation drains to the Rio Grande at low-flow during drought years,
starting in the 2004 water year (fig.
2). Results of individual seepage investigations and associated water-quality analyses were published in U.S. Geological Survey Water-Data Reports for New Mexico by water year, 1988 through 2005.
Relevance and Benefits
The Mesilla Basin monitoring network extends through New Mexico and Texas
to the United States border with Mexico. The monitoring program will contribute
to the USGS mission by providing data to help define the Nation’s
water resources, and to disseminate impartial hydrologic information to
the public. The program will benefit the cooperators and the USGS by providing
essential hydrologic data necessary for subsequent evaluation of the ground-water-flow
system and stream-aquifer relations. Ground-water data collected by the
program are used in many interpretive studies conducted by the USGS and
other agencies including the development and refinement of ground-water-flow
models. The long-term monitoring program will document ground-water conditions
including stream-aquifer relations, and provide essential data to develop
and evaluate water-management strategies.
New Mexico Water Science Center OSE HYDROLOGY BUREAU &
ISC RIO GRANDE BASIN
El Paso Field Office
Surface Water Quality Bureau
LOWER RIO GRANDE PROGRAM
New Mexico's Environment Department and the Interstate Stream Commission are working cooperatively to develop solutions to concerns regarding the quantity and quality of the water delivered to the State of Texas. Elevated salinity in the Rio Grande Project area, which extends from above Elephant Butte Reservoir, New Mexico, to Fort Quitman, Texas, has long been recognized.
NMED and NMISC facilitated the formation of Rio Grande Salinity Management Coalition consisting of water managers, the Rio Grande Compact Commission, and water user groups from Colorado, New Mexico and Texas that are actively working together to reduce and manage salinity in the Rio Grande Project area. In 2009 NMED, ISC, and the US Army Corps of Engineers completed the first phase of a Water Resources Development Act (WRDA) Section 729 Rio Grande Salinity Management Program which included a geospatial salinity database; a USGS Rio Grande Salinity Assessment Study; and Rio Grande Economic Impact Assessment study.
The New Mexico Water Resources Research Institute’s (NM WRRI) statewide program supports the state’s water research primarily at New Mexico State University, the University of New Mexico, and New Mexico Tech. Research is conducted primarily by faculty and students within the departmental structure of each New Mexico university campus. In-house staff administers the institute’s programs, conducts special research projects, and produces a variety of issue reports.
The overall mission of the NM WRRI is to develop and disseminate knowledge that will assist the state and nation in solving water problems. NM WRRI administers research projects within a variety of disciplines but that specifically have a focus on water. Users and beneficiaries are local, city, and county government; local water agencies and water users organizations; state agencies (NMDA, NMED, NMOSE, ISC, NMSLO, NMDGF), federal agencies (IBSC, USACE, USBOR, USEPA, USFWS, USGS), and state universities in New Mexico.