BROADER CONTEXT OF GROUND-WATER MONITORING

Through the 20th century, our knowledge has evolved to recognize that groundwater occurs in finite, open systems within the hydrological cycle. To assure long-term sustainable supplies, groundwater systems have to be carefully managed. Such management entails knowledge of their physical, chemical, and biological attributes, the interrelationships among the attributes, their temporal changes due to natural causes and human actions, and the ecological and environmental impacts of such changes. The gathering of indispensable information required for this purpose constitutes “monitoring”. As a scientific enterprise, groundwater monitoring is a rapidly growing field. Emerging challenges in this field include scientific-technical issues, and social-policy issues. From a scientific perspective, one needs to identify the set of critical attributes requiring observation, choose measurement sites, spatial distribution of monitoring stations and temporal frequency of measurement, and establish mechanisms for storage, retrieval and dissemination of data. Scientific objectives vary in scale from that of a single user on a local scale to the large-scale basin-wide interests of the community at large, and the linkages between groundwater and ecosystems. Monitoring is a cost-intensive venture, and one has to contend with questions of legal authority and responsibility for the cost of monitoring. As the field of groundwater monitoring progresses to enable sustainable management, it will face challenges of optimal network design, instrumentation, data acquisition, data adequacy, interpretation, and dissemination. Simultaneously, it will also face challenges of legislative authorization, institutional development, and financial support. Amidst these challenges, monitoring will likely evolve into being an integral and permanent part of integrated water resources development.