| Project Chief: Martha K. Watt | Funding (years): ongoing since 1995 |
| Phone: 609-771-3900 | Cooperator(s): New Jersey Department of Environmental Protection |
Introduction
Many current and past ground-water investigations have included the development of computer models to simulate the movement of water through local and regional aquifers. Computer models are used to help hydrologists understand flow systems and evaluate the effects of natural changes in the hydrologic cycle or changes created by human activities.
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| Figure 1. Location of archived ground-water-flow models in New Jersey. | |
Project Description
The Model Maintenance program was started in 1995 to maintain and update ground-water-flow models constructed in New Jersey. The program is designed to use standardized procedures to archive the models, update models with recent data and analytical techniques, and re-evaluate data network design. This program allows water-resource planners and managers to use the models in multiple studies in an efficient manner and at reduced costs.
Models
Eighteen ground-water-flow models that were constructed during studies in the New Jersey Water Science Center are now archived. The locations of these modeled areas are shown in figure 1. The archived models are listed in table 1. The models range in area from 2.3 to 9,000 square miles, cover diverse geologic settings, and have been updated to various degrees. Some of the models that are not archived were developed during older projects and were calibrated to hydrologic conditions through the 1970s. Reports documenting older non-archived models are listed in table 2.
Model Code
Of the 18 models archived, 16 use the MODFLOW model code and 2 use the SHARP model code to simulate ground-water flow. Since MODFLOW was published in 1988, it has undergone several updates and new capabilities have been added. Archived models that use the MODFLOW model code were run using one of the following-MODFLOW-88, MODFLOW-96, or MODFLOW-2000. All of these model codes, and some pre- and post-processors, can be downloaded from the Office of Ground Water software page. While detailed information can be found on the MODFLOW software page, a summary of system and user requirements can be found here.Disclaimer
These ground-water models are being made available to the general public as a convenience for those wishing to replicate the simulation of the ground-water flow as documented in the accompanying report. Any changes made to the model files after transmission from the USGS could have unintended, undesirable consequences. These consequences could include, but may not be limited to: erroneous model output, numerical instabilities, and violations of underlying assumptions about the subject hydrologic system that are inherent in results presented in the accompanying USGS published report. The USGS assumes no responsibility for the consequences of any changes made to the model files. If changes are made to the model, the user is responsible for documenting the changes and justifying the results and conclusions.
