Surface Water Flow Modeling
Industrial site in the Central Valley, California:
Surface water transport modeling was necessary to assess the ability of an ephemeral stream to transport contaminants across an industrial site. Regional watershed characteristics, in conjunction with localized climatic data and surface channel properties, were used to estimate flow runoff from various storm events which were then modeled relative to flow duration across the site. These data were used in a civil lawsuit to demonstrate that contaminants generated on the eastern side of the property have historically been transported across the property in the storm water flow events.
Hydrologic flow modeling to support NEPA permitting of an off-stream reservoir:
To demonstrate purpose and need for obtaining a Section 404 permit at Rueter-Hess Reservoir it was necessary to model the expected available surface water flows for storage in a reservoir on a tributary to Cherry Creek. This analysis utilized existing surface water gage data but also required the superposition of legal water supply availability on the physical surface water flow analysis. These data were also used to assess the impacts to riparian vegetation along Cherry Creek as a result of the change in the hydrologic regime due to the diversion and storage of some native flow.
Hydrologic flow modeling to support the design of a water supply reservoir to serve the Fort Knox Mine near Fairbanks, Alaska:
A water supply reservoir was required to meet the water demands for a proposed mill associated with a large gold mining project. The size of the reservoir to meet the mill demands had to be determined through hydrologic flow modeling of Fish Creek, as well as Last Chance and Solo Creeks. The analysis of the availability of surface water flows was complicated by permafrost conditions and extensive ice issues during the wintertime. The result of the analyses was that either reservoir was designed that was sufficient to meet all of the mill demands even under the harsh wintertime conditions at the site.
Reservoir operational models:
A number of reservoir operational studies have been completed using hydrologic flow data sets to assess the most efficient mode of operation to meet a projected water supply demand while, at the same time, evaluating carryover storage and minimizing spills to evaluate average and firm yields. Water management techniques are also frequently applied and include water conservation and water reuse. Reservoir operational models have been conducted on a number of sites, including Rueter-Hess Reservoir, Orlando Reservoir, Cucharas Reservoir, reservoirs to be used to optimize exchange potential, and augmentation ponds.
Cherry Creek Alluvial Modeling Project:
LWS has developed a numerical surface water/ground water flow model of the Upper Cherry Creek Basin to evaluate the average and firm yield of the Cherry Creek alluvial aquifer, based on changing hydrologic conditions associated with Cherry Creek stream flows. This study is being conducted with multiple municipal water supply entities in the Upper Cherry Creek Basin an effort to develop a regional approach to surface water and alluvial ground water supply management.