Get mapping data related to the Northwest Greater Toronto Area Transmission Corridor Identification Study. In June 2019, the Ministry of Energy, Northern Development and Mines along with Ontario’s electricity system planner, the Independent Electricity System Operator, launched the Northwest GTA Transmission Corridor Identification Study to identify an appropriate corridor of land for use by future power lines if and when the need arises.

Wetlands are lands that are seasonally or permanently flooded by shallow water. They also include lands where the water table is close to the surface. The wetland polygons are managed independently from other hydro data classes and may overlap water bodies or other hydro data. Not all wetlands have been identified and mapped. Active maintenance is ongoing province wide. The currency and accuracy of the spatial representation is variable and requires on-the-ground verification.

A source protection area (SPA) is an area of land and water governed by a Source Protection Authority, an agency, person or body. This dataset defines the geographic boundaries where each SPA's terms of reference, assessment reports and source protection plans must be developed. *[SPA]: source protection area

The Ontario Hydro Network (OHN) is a provincial medium scale originating from data with regional scales of 1: 10,000 in Southern Ontario, 1: 20,000 in Northern Ontario and 1: 50,000 in the Far North. The shoreline is taken from the OHN - Waterbody data class. This data is used for cartographic purposes and web mapping services. This product requires the use of geographic information system (GIS) software. [Ontario Hydro Network (OHN) User Guide (Word)](https://www.sdc.gov.on.ca/sites/MNRF-PublicDocs/EN/CMID/OHN%20-%20UserGuide.docx)

This data breaks down estimated hunter and harvest numbers by: * wildlife management unit (WMU) * calendar year Harvest and active hunter numbers are estimates based on replies received from a sample of hunters and are therefore subject to statistical error. Additional technical and statistical notes can be found in the data dictionary.

Prior to January 1, 2008, fishing divisions were administrative units to manage, monitor, assess and regulate recreational fisheries. Each zone was based on angler usage and ecological/geographic patterns. Refer to [Fisheries Management Zone for boundaries after 2008](/dataset/fisheries-management-zone).

A feature is a representation of a real world object, such as a lake, stream, dam or rapid. There are three hydrographic feature classes:  points, lines and polys. All may impede or be hazardous to waterflow and/or navigation on a watercourse or waterbody. This data shows natural and manmade point features. Examples include: * waterfalls * rapids * rocks * Sea Lamprey barriers * shipwrecks This product requires the use of geographic information system (GIS) software. [Technical Bulletin: Data migrated to new Ontario Hydro Network (OHN) - Hydrographic Feature Data Classes (PDF)](https://geohub.lio.gov.on.ca/datasets/mnrf::ontario-hydro-network-ohn-hydrographic-point/)

Watercourses are line features - natural or manmade - that represent the location of flowing surface water. This product requires the use of geographic information system (GIS) software.

Historical Oil Fields are subsurface accumulations or 'pools' of crude oil designated as such for the purposes of the Oil, Gas and Salt Resources Act. This product requires the use of geographic information system (GIS) software.

This data contains an Index identifying Ontario Base Map map tiles. Eastern and Southern Ontario is covered at a scale of 1:10,000. Northern Ontario is covered at a scale of 1:20,000. We are no longer updating this data. It is best suited for historical research and analysis. This product requires the use of geographic information system (GIS) software.