Groundwater Resource Studies

The Groundwater Resources Study (GRS) series seeks to better the understanding of Ontario’s groundwater resources through the collection, evaluation and distribution of geoscience data. The main objective of the series is to provide accurate information on a range of groundwater-related themes, including local- to watershed-scale aquifer characterization and delineation; geologic controls and influences on groundwater quantity and quality; and methods development. Products of the groundwater program include geoscience reports, data sets and protocols for information collection and handling. Geoscience information generated through the series will find application in the protection and sustainable management of the province’s groundwater resources.

GRS 1 - Central Lake Ontario Conservation Authority Groundwater Resources Study

Groundwater Resources Study 1 Central Lake Ontario Conservation Authority Groundwater Resources Study This digital release contains a set of maps and a report, in portable document format (.pdf), that describe the groundwater resources of the Central Lake Ontario watershed area. There are 3 groundwater regimes in this watershed: the Oak Ridges Moraine, overburden aquifers in the Iroquois Plains, and aquifers associated with the Ordovician bedrock formations. The hydrogeology of these aquifers is characterized in a set of maps and accompanying report, and includes Quaternary and Paleozoic geology, bedrock topography, overburden thickness, sand/gravel thickness, water table, potentiometric surface and potential recharge/discharge areas. Aquifer vulnerability is assessed from “depth to water table” and “depth to first aquifer” maps. Available on 1 CD-ROM. $20.00.

View GRS 1 metadata or download GRS 1.

GRS 2 - Essex Region Groundwater Resources Study

This digital release contains a set of maps and a report, in portable document format (.pdf), that describe the groundwater resources of the Essex Region watershed area. There are 3 main groundwater regimes in this watershed: a “contact aquifer” comprising the highly-weathered upper portion of bedrock and the drift deposits that directly overly bedrock; an area of relatively thick glacially-derived sand and gravel deposits in the Leamington–Harrow area; and deeper bedrock aquifers associated with the predominantly carbonate rocks of the Devonian-age Lucas and Dundee formations. Recessional moraines and buried eskers in overburden, and karstic (i.e., solution-enhanced) fractures in bedrock potentially influence the hydrogeology of these aquifers. The hydrogeology of these aquifers is characterized in a set of maps and accompanying report, and includes Quaternary and Paleozoic geology, bedrock topography, overburden thickness, sand and gravel thickness, groundwater quality, water table, potentiometric surface and potential recharge and discharge areas. Aquifer vulnerability is assessed from “depth to water table” and “depth to first aquifer” maps. Available on 1 CD. $20.00.

View GRS 2 metadata or download GRS 2.

GRS 3-Three-Dimensional Mapping of Surficial Deposits in the Regional Municipality of Waterloo, Southwestern Ontario

This digital data release contains information regarding the three-dimensional distribution and character of surficial materials that may form groundwater aquifers and aquitards within the Regional Municipality of Waterloo in southwestern Ontario. The data sets are organized into a series of folders, each containing information of varying type and format. These include 1) a summary report; 2) ArcInfo® grids and comma-delimited (.csv) files of modelled surfaces; 3) GoogleTM Earth (.kmz) files depicting borehole location and stratigraphic information as well as isopach and structural contour maps of modelled units; 4) high resolution plates depicting cross-sections and aquifer recharge and vulnerability maps; 5) a beta section viewer for slicing the block model along user-defined lines; and 6) the subsurface data set used for the construction of the three-dimensional block model. The data are available on 1 CD. $20.00.

View GRS 3 metadata or download GRS 3.

GRS 4 - Long Point Region Groundwater Resources Study

This Groundwater Resources Study describes the groundwater resources of the Long Point Region watershed area. The study identifies 3 groundwater regimes: shallow overburden aquifers; 2 deeper, discontinuous, confined overburden aquifers; and aquifers associated mainly with Dundee Formation and Detroit River Group bedrock. The hydrogeology of these aquifers is characterized in a set of maps and accompanying report, including Quaternary and Paleozoic geology, bedrock topography, overburden thickness, sand/gravel thickness, water table, potentiometric surface and potential recharge/discharge areas. Aquifer vulnerability is assessed from “depth to water table” and “depth to first aquifer” maps. Ambient hydrogeochemistry of the 3 groundwater regimes is assessed through a comprehensive analysis of groundwater samples from 91 domestic water wells. The study’s report and accompanying figures, maps, tables and appendix data are provided in 1 portable document format (.pdf) file on 1 CD. $20.00.

View GRS 4 metadata or download GRS 4.

GRS 5 - Karst of Southern Ontario and Manitoulin Island

This digital data release contains reconnaissance-level field data and polygons depicting the nature and regional distributions of karstification of Paleozoic bedrock units within thin drift and exposed bedrock regions of southern Ontario and Manitoulin Island. Field photos of key karst features such as caves, sinkholes, disappearing streams and springs, and solution-enhanced joint sets are highlighted for selected regions on the digital map. The relative response of the various sedimentary rock units to karstification is placed within a stratigraphic and geographic context. The data are organized into a series of folders of varying type and format. These include 1) main karst report to accompany map; 2) an ArcGIS® map; and 3) a second report prepared by Golder Associates and OGS staff describing three-dimensional data in the form of field site descriptions and joint measurements, digital core logs, and geophysics from select regions to further delineate/investigate the vertical extent of particular surficial karst features. The data are available on 1 DVD. $25.00.

View GRS 5 metadata or download GRS 5.

GRS 6 - Groundwater Resources of the Credit River Watershed

This Groundwater Resources Study describes the groundwater resources of the Credit River watershed area. The groundwater resources of this area are strongly influenced by the Niagara Escarpment, which bisects the watershed, and 4 buried bedrock valleys. Significant aquifers in the watershed include the Oak Ridges, Orangeville and Paris moraines, the buried bedrock valleys and the Amabel and Guelph bedrock formations. The hydrogeology of these aquifers is characterized in a set of maps and accompanying report, including Quaternary and Paleozoic geology, bedrock topography, overburden thickness, sand/gravel thickness, water table, potentiometric surface and potential recharge/discharge areas. Groundwater discharge and baseflow is assessed with the assistance of subwatershed streamflow data. Available on 1 CD. $20.00.

View GRS 6 metadata or download GRS 6.

GRS 7 - Karst Delineation and Sinkhole Investigation in the Ausable Bayfield Conservation Authority Watershed and Surrounding Area

This Groundwater Resources Study describes a study of sinkholes and karstic features in the Ausable Bayfield watershed of southwestern Ontario. The study included compilation of previously mapped sinkhole data, mapping of previously unmapped sinkholes, completion of 2 boreholes to the Lucas and Dundee bedrock formations, completion of downhole geophysics, long-term groundwater level and quality monitoring and a bromide tracer test. Available as portable document format (.pdf) and Microsoft® Excel® 2003 (.xls) files on 1 CD. $20.00.

View GRS 7 metadata or download GRS 7.

GRS 8 - An Investigation of the Buried Bedrock Valley Aquifer System in the Schomberg Area of Southern Ontario

This Groundwater Resources Study investigates a buried bedrock valley aquifer system in the Schomberg area of south-central Ontario. The study included compilation and interpretation of existing subsurface data from water wells and boreholes, completion of a ground seismic survey, completion of a deep continuous-cored borehole near Schomberg and downhole geophysical measurements of this borehole. Results provide insight into the hydrostratigraphy of this buried bedrock valley aquifer system, which is part of the regional Laurentian valley system, and buried overburden valleys associated with the Holland Marsh. Available as one portable document format (.pdf) file on 1 CD. $20.00.

View GRS 8 metadata or download GRS 8.

GRS 9 - An Investigation of the Buried Bedrock Valley Aquifer System in the Caledon East Area, Southern Ontario

This Groundwater Resource Study investigates a buried bedrock valley aquifer system in the Caledon East area of south-central Ontario. The study included compilation and interpretation of existing subsurface data from water wells and boreholes; completion of a ground seismic survey; completion of a deep, continuous-cored borehole southwest of Caledon East and downhole geophysical measurements of this borehole; and completion of 2 rotary drill boreholes to define bedrock surface, provide preliminary stratigraphic information and confirm seismic stratigraphic interpretations. Results provide insight into the geology and hydrostratigraphy of the buried valley aquifer in the Caledon East area, which is part of the regional Laurentian valley system, and aid in construction of a hydrostratigraphic model of the study area. Available as one portable document format (.pdf) file on 1 CD. $20.00

View GRS 9 metadata or download GRS 9.

GRS 10 - Three-Dimensional Mapping of Surficial Deposits in the Brantford–Woodstock Area, Southwestern Ontario

This digital data release contains information regarding the three-dimensional distribution and character of surficial materials that may form groundwater aquifers and aquitards within the Brantford–Woodstock area of southwestern Ontario. The data sets are organized into a series of folders, each containing information of varying type and format. These data include 1) a summary report (.pdf); 2) ESRI® ArcInfo® grids and comma-delimited (.csv) files of modelled surfaces; 3) Google Earth™ mapping service (.kml, .kmz) files depicting borehole location and stratigraphic information as well as isopach and structural contour maps of modelled units; 4) graphic (.htm, .jpg, .tif) and written (.doc, .htm) borehole logs, high-resolution (.jpg) photographs of core and analytical data (.xls) for samples collected, all presented in a hyperlinked .htm format; 5) high-resolution plates (.pdf) depicting north-south and east-west cross sections and aquifer recharge and vulnerability maps; 6) a section viewer (.exe) for slicing the block model along user-defined lines; and 7) an abbreviated version of the subsurface data (.mdb) used for the construction of the three-dimensional block model which includes borehole collar and stratigraphic information, picks data, and screen depth and water level information. The data are available on 1 dual-layer DVD. $25.00.

View GRS 10 metadata or download GRS 10.