This paper is the first in a series of reports concerning data assembled during the Pilot Watershed Study (PWS), a major component of the Soil and Water Environmental Enhancement Program (SWEEP). As part of the PWS, a variety of materials have been delivered to the Ontario Land Resource Unit (OLRU) of Agriculture Canada by BEAK Consultants, Ecologistics, and Ecological Services for Planning, the contractors involved in implementing the PWS. The purpose of this report is to assess and document the digital data received from the PWS which i) have potential application to the Indicators of Risk of Water Contamination (IROWC) project at the OLRU, and which ii) are appropriate for incorporation into the OLRU database. The paper documents the types of digital data available, assesses their spatial and temporal resolution and accuracy, and estimates the degree to which data layers can be integrated. The paper concludes that the spatial coverages and associated attribute information can be readily integrated, and that the PWS database will prove quite useful in assessing IROWC at a variety of temporal and spatial scales.