DEVELOPMENT OF A GROUNDWATER DATA EXCHANGE NETWORK FOR INTEROPERABLE DATA EXCHANGE AND MEDIATION BETWEEN THE U.S. AND CANADA

The need for wide-spread groundwater monitoring is profound and has been internationally recognized as a major data availability gap for managing groundwater resources. To meet this need, the U.S. initiated a National Ground Water Monitoring Network (NGWMN) envisioned as a voluntary, integrated system of data collection, management and reporting that will provide the data needed to address present and future groundwater management questions. An interoperability experiment was organized within the Open Geospatial Consortium (OGC) to evaluate international data exchange standards as a means of federating groundwater monitoring networks across the U.S. / Canadian border.

The goal of the interoperability experiment is to build upon the Canadian Groundwater Information Network (GIN) and the U.S. NGWMN Data Portal to test a mechanism by which policy makers, academics and the public could access groundwater information through one seamless web-based application from distributed data sources across the U.S. and Canada. This data exchange network facilitates the retrieval of groundwater data on an as-needed basis from multiple, distributed data repositories. The network allows data to continue to be housed and managed locally, while being accessible for the purposes of groundwater monitoring on both a nationaland international scale.

Access to dispersed data stored in heterogeneous formats is provided through standards-based mechanisms, which leverage the OGC data exchange standards and information models. WaterML2.0, an evolving international standard for water observations encodes groundwater levels and is exchanged using the OGC Sensor Observation Service (SOS) standard. Ground Water Markup Language (GWML) encodes well log, lithology and construction information and is exchanged via the OGC Web Feature Service (WFS) standard. Data exchange between distributed repositories has been achieved and a central mediation hub, which performs both format (semantic) and nomenclature (syntactic) mediation of the raw data and outputs this information in a single common format. This architecture makes groundwater data from the U.S. and Canada to be accessed, mapped, re-organized and delivered through a single web application.