An Interdisciplinary Assessment of Regional-Scale Nonpoint Source Ground-Water Vulnerability: Theory and Application (2001)


The availability of potable ground-water supplies is a major environmental quality and human health concern throughout the United States. In the study reported here, a geographic information system (GIS) environment is used to apply an Integrated Earth Science–Economics Model (IESEM) that combines a regional-scale nonpoint source vulnerability assessment tool with a specific remediation measure to avoid unnecessary agricultural production costs related to the use of agrochemicals. Based on two screening indices that utilise earth science information, the vulnerability assessment tool functions in a spatial analysis to target areas vulnerable to ground-water contamination

This study demonstrates that using an IESEM in a GIS framework provides an ability to assess, at a regional scale, the trade-offs among pesticide use, crop yield, and groundwater treatment.

Geographical scope

Pearl Harbour basin on the island of Oahu, Hawaii.

Non-quantified impacts

The regulatory program with the maximum positive expected present value of net benefits is the most efficient and should be implemented. these findings are meant only to demonstrate the cost effectiveness of the coordinated agricultural and resource programs and do not reflect economies of scale or the value of ground water lost.

Quantifiable impacts

The application of the IESEM in a cost-effectiveness analysis for 17 coordinated programs showed that 12 of the programs demonstrated substantial cost savings, ranging from USD 8.0 million to USD 244.0 million, that could accrue to producers if a regional vulnerability assessment were coordinated with a wellhead treatment program.

Specific figures per program are given in the report.



Study type

Case studies and cost-effectiveness analysis

Economy sector

Water, Environment, Agriculture