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WHPA performs modeling to meet regulatory requirements, for water supply analysis, and surface water hydrological analysis. Specifically our modeling supports:

  • wellfield siting and design
  • Ranney® Collector Well siting and design
  • wellfield optimization
  • hydrogeologic characterization
  • water quality and hydrochemistry
  • mine impact analysis
  • wellhead protection area delineation
  • watershed modeling and TMDL analysis
  • pumping impact studies
  • contaminant transport
  • floodplain delineation and construction impact analysis
  • stormwater flow analysis

WHPA is nationally recognized as a leader in developing and applying groundwater hydraulic models. For over 20 years our engineers and hydrologists have been modeling hydrologic systems in various geographic settings across the United States. Modeling environmental processes requires an understanding of the physics of the integrated hydrologic, geologic, and landscape systems. We understand how problems appear from a number of perspectives within a community. Our work requires an experienced, competent, scientific and management team to assure the complementary effort of a group of hydrologists, engineers, geologists, and geochemists.

Groundwater Flow Modeling

WHPA has been developing and applying groundwater flow models to aid community and private water utilities across the United States for over 20 years. Groundwater modeling provides information with which water suppliers and water-resource planners are able to make educated decisions about the future of the resource and the water supply. WHPA has helped communities with:

  • Wellfield Siting and Design
  • Wellfield Optimization
  • Water Quality and Hydrochemistry
  • Wellhead Protection Area Delineations
  • Watershed Modeling and TMDL analysis
  • Pumping Impact Studies
  • Conjunctive Use Evaluations

Surface Water Modeling

WHPA uses the following programs for surface-water and stormwater modeling: HEC-1, HEC-RAS, HSPF, WMS, and SWMM. WHPA’s surface-water capabilities and services include:

  • Creation of stormwater flow and stream flooding models.
  • Evaluation of the increase in stormwater runoff due to future development.
  • Modeling to predict the effect of stormwater runoff on receiving water quality and recommend best management practices for improvement.
  • Watershed modeling and TMDL analysis.
  • Contaminant assessment of receiving waters.
  • Floodplain delineation and construction impact analysis.

WHPA hydrogeologists and engineers perform the hydraulic modeling required by regulatory agencies to meet the Phase II stormwater management requirements and to analyze the impact of development in floodplain areas.

Model Code Development

WHPA has developed new model code and modified existing code for the purposes of simplifying the modeling process or to provide solutions other models cannot. Scientists at WHPA developed EPA’s wellhead protection area delineation model: WhAEM. This new analytic element model is being used throughout the country by state agencies and consultants.

Most recently we have developed a new groundwater program for flow in the vicinity of horizontal wells and Ranney® Collector Wells (patent pending). The collector well model is embedded in the TimML 3-D analytic element code to include the effects of regional groundwater flow as well as nearby surface waters. This tool allows the modeler to construct a regional 2-D model of groundwater flow then ‘turn on’ the 3-D analysis for the collector well arms, local surface waters, and nearby wells. This tool allows WHPA provide optimal well siting for large well systems and to provide optimal design specifications for high-capacity collector wells.

Horizontal and Collector Well Modeling

WHPA has over 50 years of combined experience in the development and application of models for horizontal and radial collector wells. WHPA can provide designers and operators with answers to important and difficult questions, such as:

  • What is the total capacity of the well?
  • How does the well interact with nearby vertical wells and sources of contamination?
  • How much water does the well capture from nearby surface waters?
  • What is the distribution of residence times for induce recharge from surface water?
  • What are the expected drawdowns in the aquifer?
  • How can the well be pumped to optimize the overall operation?
  • How are seasonal variation expected to affect water quality?

Groundwater flow patterns in the vicinity of a horizontal or a Ranney® Collector Well are very complex. The well interacts with regional flow in the aquifer, and usually also with nearby wells and surface waters. In many cases, the collector arms extend beneath a nearby river, as a method of inducing recharge to the aquifer. A properly constructed model of a collector well near a river must be able to examine the effects of this setting.

Contaminant Fate and Transport

WHPA has done extensive research and published new techniques for contaminant fate and transport modeling in the saturated zone. The principals in the firm have developed risk-based tools for evaluating the potential for contaminant releases to generate threats to down-stream water users and exposure to ecosystems.

  • Electric Power Research Institute (EPRI) - The research work has been primarily for the EPRI. The company developed new insights into contaminant risk by using numerical experiments (one, two, and three-dimensional flow and transport models) to test the sensitivity of a solute pulse release to variation in release characteristics. These new tools and metrics have been used to define the risk of contamination from environmental releases based on the chemical and toxicological characteristics of the contaminant. To download this EPRI document, click here.
  • WHPA evaluated fate and transport of a metals and VOC contaminant plume that had migrated towards a community water supply well field. One-dimensional modeling of transport along pathlines was used to evaluate the exposure potential in a stream and the well field.
  • Groundwater modeling was combined with a contaminant transport model to consider the fate of a contaminant plume in the industrialized area in Northwest Indiana. A contaminated site was considering the loading that may occur along a headwater stream for an anadromous fishery that used this stream system. This work was done for a state regulatory agency.
  • A contaminant plume was found upgradient of a community water supply well field and the state utility regulatory agency asked for advise about the extent to which the contamination could cause problems for the community water supply. This project included fate and transport modeling, site data analysis as well as eventual expert witness testimony.