Comprehensive work in ground water hydrology and resource development has been completed by Lytle Water Solutions personnel in varied geologic terranes, including unconsolidated alluvial deposits, sedimentary rock, limestones and dolomites, volcanic rock, and crystalline rock. Areas of expertise in ground water hydrology, and descriptions of representative projects, are presented below.
Ground Water Development
To evaluate ground water production capabilities in the confined alluvial aquifer of the San Luis Valley, over 17,500 ft. of drilling and well completions were done, along with geophysical logging and water quality sampling, to characterize the developable ground water resources to a depth of 2000 feet beneath approximately 100,000 acres of land. Using these data, ground water modeling was used to assess the long-term expected yield to provide municipal water supplies.
Municipal Water Supplies
Ground water-dependent municipalities and special districts along the Front Range of Colorado are primarily dependent on the water resources of the Denver Basin bedrock aquifers. Due to growth, these municipalities and districts have needed to expand their water supply capabilities and LWS personnel have designed, observed construction of, and tested dozens of deep bedrock wells, ranging in depth from 400 to over 2800 feet.
A 2,500-foot exploratory well was drilled in central Florida to investigate the ground water development potential and depth of the fresh water/salt water interface. The exploratory program included drill-stem testing, geophysical logging, and downhole packer testing. The exploratory program culminated in the successful development of a 6,000-gallon per minute municipal water supply well.
Test Well Drilling Programs
A heterogeneous alluvial aquifer associated with Cherry Creek, a tributary to the South Platte River, was methodically evaluated through a test-drilling program, including aquifer testing, to assess the best locations for alluvial production wells. Subsequent water well drilling programs developed production wells at these sites.
A test well drilling program was conducted near Cedar Bluffs, Iowa, to evaluate locations where a production well could be sited to provide water to a manufacturing facility without inducing high TDS-water to the well.
The city of Cheyenne, Wyoming, was contemplating water supply development in an aquifer in an area with little geologic or hydrogeologic data. Published reports and sparse well data were used from the area, along with interpretation of seismic reflection data, to initially characterize the aquifer and to select test drilling sites. Test well drilling and aquifer testing were then used to assess aquifer characteristics. A ground water model will be used to assess the long-term water supply production capability from the aquifer.
LWS staff have routinely performed geologic reconnaissance, remote sensing evaluations, and commissioned use of a variety of geophysical methods to assist in characterization of hydrogeologic conditions.
Ground Water Supply Planning
Sixteen municipal and special water districts in El Paso County, Colorado, participated in a regional water supply planning study in Colorado to evaluate how future water demands would be met at buildout and how regional cooperation could be used to develop integrated water supply systems.
Water supply planning for a number of municipalities and special districts in Colorado has included evaluation of demand versus supply projections, with the attendant scheduling of new Denver Basin well installations.
Ground Water Modeling
Analytical and numerical modeling tools were used to assess long-term sustainable yield from the confined alluvial aquifer in the San Luis Valley (Colorado) that is being recharged by surface water flows. The modeling was used to assess impacts to existing vested surface and ground water rights to evaluate a Water Court application for new water rights.
An analytical ground water model was used to assess water management techniques for the Parker Water and Sanitation District to deal with significant water level declines and the attendant well production loss. The model evaluated the most efficient well operation to minimize well-to-well interference in its well fields.
A numerical ground water model was constructed to evaluate the sustainable yield of a coastal aquifer in Florida and to evaluate the risk of seawater intrusion associated with long-term use.
A ground water model was used to support the permitting of a 15 million-gallon per day wellfield proposed by a major utility in central Florida. The model was used to forecast water level changes, changes in discharge of several major springs, and change in the position of the fresh/salt water interface.
Aquifer Storage and Recovery (ASR)
Declining water levels in the Denver Basin bedrock aquifers has necessitated the evaluation of alternative technologies to extend the useful life of the aquifers. A 6-year research project was completed in the southeastern Denver metro area which evaluated the technical, economic, institutional, water quality and legal issues associated with deep bedrock aquifer storage and recovery (ASR). This work won the ACEC Engineering Excellence Award.
LWS has assisted the Cheyenne Board of Public Utilities (BOPU) with a Managed Aquifer Recharge, Storage and Recovery (ASR) pilot study to evaluate various aquifer recharge technologies. Research has included the use of a rapid infiltration basin and an Ogallala aquifer injection well. The primary objective of the pilot study was to evaluate whether recharge methods could improve the productivity and sustainability of the Ogallala aquifer in BOPU's well fields.