As part of a study to analyze the effects of sea-level rise on groundwater resources of Colonial National Historical Park, a monitoring network was established on Historic Jamestown Island, Virginia, to evaluate current levels of and changes in groundwater elevation and water quality. The monitoring network includes 45 wells and piezometers, 3 marsh sites, and 2 surface-water sites distributed across 5 sampling locations on Jamestown Island. Field parameters, including water temperature, specific conductance, pH, and dissolved oxygen, were collected at the marsh and surface-water sites. Field parameters and water levels were collected from the wells and piezometers. Information provided in this data release was collected by U.S. National Park Service staff. Although these data have been used by the U.S. Geological Survey, U.S. Department of the Interior, no warranty expressed or implied is made by the U.S. Geological Survey as to the accuracy of the data. This data release consists of three Excel files and three pdf files. The Jamestown_monitoring_locations Excel file includes coordinates and U.S. Geological Survey site numbers for the monitoring sites. The Jamestown_field_parameters Excel file contains the field parameter data collected at the monitoring sites. The Jamestown_water_level_elevations Excel file is divided into five sheets, with each sheet containing water-level elevations collected from individual well clusters located at each of the five sampling locations. The pdf files contain the field notes collected by National Park Service personnel during site visits.