This data is intended to identify Canadian fresh waters which require additional measures (e.g., ballast water exchange and treatment) prior to release, as described in https://tc.canada.ca/en/marine-transportation/marine-safety/list-canada-s-designated-alternate-ballast-water-exchange-area-fresh-waters-tp-13617e-2021. The data is not intended for navigation purposes.According to Canada’s Ballast Water Regulations, vessels which are managing ballast water to meet the ballast water performance standard cannot release ballast water into fresh waters unless that ballast water was first exchanged in accordance with the ballast water exchange standard. For the purpose of this requirement, Canadian fresh waters are the following:- the waters at the Port of Kitimat and waters in or upstream of the Kitimat Arm, east of a line between Hilton Point and Steel Point;- the waters at the Port of Stewart and waters in or upstream of the Portland Canal, north of a line between Portland Point and Ramsden Point;- the waters of all Fraser River ports that are: -- east of Tilbury Island in the main arm of the Fraser River including Annacis Island and New Westminster docking areas; and -- east of the eastern tip of Mitchell Island in the north arm of Fraser River;- the waters of the Saguenay River ports and waters upstream of L’Anse-Creuse;- the waters of all St. Lawrence River ports and waters west of the east point of Ile d’Orléans including the port of Quebec City;- all Canadian waters of the Great Lakes Basin; and- the waters of Happy Valley-Goose Bay and waters of Lake Melville west of Rabbit Island.Legal Constraints: Users should be aware that the polygons depicting areas requiring additional measures to manage ballast water are intended for illustration only and should not be used for navigational or legal purposes.

This dataset contains Lake Ontario prey fish abundance and distribution statistics, collected every year during spring and fall bottom trawl surveys. The New York State Department of Environmental Conservation and the U.S. Geological Survey have conducted annual, spring and fall bottom trawl surveys in U.S. waters of Lake Ontario since 1978. In 2015, the Ministry of Natural Resources and Forestry started contributing to this program to include survey coverage in Ontario waters. The ministry also intermittently conducts mid-water trawling during the summer months on a limited geographic area largely confined to the Eastern Basin. The survey has varied sample distribution across lake depths and jurisdictions. The south shore of Lake Ontario has well-distributed coverage of depths between 8 and 200 metres. Coverage along the north shore is less uniform due to a lack of suitable trawl sites at shallower depths.

This is a magnitude 5.0 earthquake scenario under Lake Ontario, very close to Toronto. This fault is not known to be active but demonstrates a plausible earthquake scenario for Toronto region.

The contaminants in fish database is a compilation of contaminant data analysed from fish tissue at the Fresh Water Institute from 1970 to 2005. Data include lab number, region, analysis, organs, species, lake, form (whole fish, headon dressed, headless dressed), weight, and length and contaminant concentrations. Total mercury was the predominant contaminant measured. Results were expressed as ppm or ppb based on the parameter analyzed. Concentrations are expressed based on wet weight.

The Great Lakes Migrant Waterfowl Surveys provide periodic data on waterfowl abundance, spatial and temporal distributions, and use along the shorelines of major water bodies and river systems in Ontario during mostly during spring and fall, and to a lesser extent during summer and winter, seasons. The primary survey area covers the shoreline and nearshore (~1km) waters of the Lower Great Lakes region of Ontario, specifically including the St. Lawrence River, Lake Ontario, Niagara River, Lake Erie, Detroit River and Lake St. Clair and associated major marshes and embayments. Aerial surveys, typically flown several times within spring (March –May: 1969, 1971, 1972, 1975 –1979, 1981, 1982, 1984 –1988, 1991 –1996, 1998 –2003 & 2009 –2011) and fall (September –December: 1968, 1970, 1971, 1974 –2003 & 2009 –2011) survey periods, have been conducted periodically on a relatively regular basis (approx. 5-10 years) along the Lower Great Lakes shorelines between 1968 and 2011. Smaller-scale surveys also have been conducted periodically during summer (June –August: 1968 –1970, 1972, 1974, 1975, 1977, 1982, 1984, 1986, 1989, 1999 & 2002) in this region. This survey often has been conducted in conjunction with the Midwinter Survey, so its data (up to 2004) also are included in the CWS Migrant Waterfowl Surveys database (Year ≥2004 & Month = January & February).Data from several aerial surveys conducted periodically during the non-breeding period outside the Lower Great Lakes region also are included in this database. Spring and fall surveys have been conducted along the shorelines and nearshore waters of the Upper Great Lakes region of Ontario, specifically at St. Clair River (Fall 2012 & 2013), Lake Huron (Fall 1973, 1996; Spring 1974) / Georgian Bay (Fall 1973, 1996, 2012 & 2013) & Lake Superior (Fall 2000). Aerial surveys also have been conducted inland in southeastern Ontario along the Rideau River (Fall 1998 & Spring 1999).

Data includes: * The Lake Superior watershed * The Lake Huron watershed * The Lake Erie watershed * The Lake Ontario watershed * The St. Lawrence River watershed

This layer comprises all the available water wells in GIN (Yukon, British Columbia, Alberta, Saskatchewan, Manitoba, Ontario, Quebec, Nova Scotia and Newfoundland and Labrador) and published through the open data platforms. This layer is a combination of all individual provincial and territorial layers. The original databases are dynamically converted by an automatic process managed by Natural Resources Canada (Groundwater Information Network).

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/)

Get data on Lake Ontario tagged Atlantic salmon recaptures. This dataset represents tagged adult Atlantic salmon that were released and then recaptured by anglers. These fish were used as brood stock (breeding) in the Ministry of Natural Resources and Forestry’s fish culture program. All fish were tagged with a streamer tag near the dorsal fin. Each tag has a unique number and a phone number so anglers can call and let the ministry know about their catch. The data includes: * tagging date * recapture date * tag number/colour * location released * location recaptured * days since released * distance travelled

Point locations of water and weather monitoring stations used by the [Surface Water Monitoring Centre](http://www.ontario.ca/page/surface-water-monitoring-centre) to assess flood and drought conditions across Ontario. Monitoring station types include: * streamflow gauge stations * Environment and Climate Change Canada climate stations * Ministry of Transportation road weather stations * Ministry of Natural Resources (MNR) fire weather stations * MNR snow network stations (wildlife) * MNR snow survey stations (weather) * Ontario Power Generation snow survey stations (weather)