The Ontario Watershed Boundaries (OWB) collection represents the authoritative watershed boundaries for Ontario. The data is based on a framework similar to the Atlas of Canada Fundamental Drainage Areas and the United States Watershed Boundary Dataset, however it adopts a more stringent scientific approach to watershed delineation. The Ontario Watershed Boundaries (OWB) collection includes five data classes:OWB Main (OWB) (Download: Shapefile | File Geodatabase | Open Data Service | QGIS Layer )all watershed levels from primary to quaternary, and level 5 and 6 watersheds for select areas of the province;OWB Primary (OWBPRIM) (Download: SHP | FGDB | ODS | QLR-Diverted Flow | QLR-Natural Flow)all primary watersheds or major drainage areas (WSCMDA) in the Canadian classification;OWB Secondary (OWBSEC) (Download: SHP | FGDB | ODS | QLR*)all secondary watersheds or sub drainage areas (WSCSDA);OWB Tertiary (OWBTERT) (Download: SHP | FGDB | ODS | QLR*)all tertiary watersheds or sub-sub drainage areas (WSCSSDA);OWB Quaternary (OWBQUAT) (Download: SHP | FGDB | ODS | QLR)all quaternary watersheds or 6-digit drainage areas (WSC6).*Display issues in QGIS are currently being investigated for these services. See the RSS feed below for details.IMPORTANT NOTE: The OWB data replaces the following data classes:Provincial Watersheds, HistoricalAdditional DocumentationUser Guide for Ontario Watershed Boundaries (Word)Watershed Delineation Principles and Guidelines for Ontario (Word) Atlas of Canada 1,000,000 National Frameworks Data, Hydrology - Fundamental Drainage Areas United States Geological Survey Watershed Boundary Dataset (Website)

Status Completed: Production of the data has been completed

Maintenance and Update Frequency Irregular: data is updated in intervals that are uneven in duration - usually after the completion of major updates to source data (e.g. OIH), but could also include spot updates and expansion of the dataset over time based on user needs. RSS FeedFollow our feed to get the latest announcements and developments concerning our watersheds. Visit our feed at the bottom of our ArcGIS Online OWB page.

Contact Ontario Ministry of Natural Resources - Geospatial Ontario, geospatial@ontario.ca

Rivers included in this map series include:

• Albany
• Winisk
• Severn
• Moose
• Ekwana
• Attawapiskat

The maps display gauging systems such as cost share agreement gauges, Water Survey of Canada gauging stations and Meteorological Survey of Canada Climate stations. Dams, their jurisdictional owners and Far North First Nations communities are included.

Conservation Authority Administrative Areas are lands under the jurisdiction of a Conservation Authority.

A total of 31 Conservation Authorities operate in southern Ontario and an additional five Conservation Authorities deliver programs and services in northern Ontario. Conservation Authorities, created in 1946 by an Act of the Provincial Legislature, are mandated to ensure the conservation, restoration and responsible management of Ontario's water (watersheds), land and natural habitats through programs. This layer is part of what was known as the OMNR Fundamental Dataset.

The Enhanced Flow Direction Grid is a grid representing surface flow directions derived from Version 2.0 Digital Elevation Model (DEM) with the added enhancement of having the photogrammetrically mapped hydrology (WRIP Water Virtual Flow and NRVIS water body segment) embedded within the grid so that known hydrology is accurately represented within the grid.

Also included in version 2 is an alternative assignment of flow direction to shoreline areas. The inclusion has the following effects: Brings the limit of the Flow Direction grid closer to the shoreline resulting in a cleaner product; Allows for the delineation of distinct shoreline catchments not possible in the previous EFD product; Minimizes effects of shoreline bleeding (erroneous catchments being formed in -no-data- areas usually upstream of project areas); and Assigns proper flow directions to minor bays and inlets.

To cover Ontario the grid has been divided into 16 pieces, existing in their respective UTM zones 15, 16, 17, and 18. Each grid covers major watersheds within these zones. The naming conventions of the grid follow the naming conventions of the Secondary and Tertiary Provincial watershed layers. The resolution of the Enhanced Flow Direction Grid is the same as the Provincial Digital Elevation Model - 10m for southern Ontario (where 1:10,000 base data exists) and 20m for Northern Ontario (where 1:20,000 base data exists). Currently, 16 of the 16 grids covering Ontario are included in the package. There are index shapefiles included within the package to show the extent of each grid.

The Aquatic Habitat Inventory contains lake, river and stream survey data collected from the 1950s to the 1990s. These surveys were conducted to acquire basic knowledge of the chemical, physical and biological characteristics of Ontario’s lakes, rivers, and streams to aid in watershed planning, aquatic habitat conservation and fisheries management.

The Ontario Ministry of Northern Development, Mines, Natural Resources and Forestry compiled brook trout presence and absence data for rivers and streams within the Mixedwood Plains Ecozone of Ontario. Data from hundreds of electrofished sites were grouped into two time periods, past (1970-1980) and recent (2000-2010), to quantify the change in brook trout occupancy in streams of the Mixedwood Plains Ecozone in Ontario at different spatial scales. The data include information for five spatial scales: 1) tertiary watersheds; 2) quaternary watersheds; 3) the well-sampled Credit River-Sixteen Mile Creek tertiary watershed; and, 4) sites within 50 m of each other were sampled in both the past (1970-1980) and recent (2000-2010) periods, and 5) at each spatial scale brook trout occupancy along the longitudinal axes of the rivers was assessed using Strahler stream order. This data set will be cited in a manuscript that quantifies the declines in brook trout occupancy in rivers and streams of southern Ontario. Methods Brook trout presence or absence data were extracted from a compilation of electrofishing sampling data collected by the Ontario Ministry of Northern Development, Mines, Natural Resources and Forestry, 22 Conservation Authorities, Fisheries and Oceans Canada, and the Royal Ontario Museum. Additional site data include tertiary or quaternary watershed codes, the number of sites where brook trout were present, the number of sites where brook trout were absent, the Strahler stream order of the sites, and the mean number of times the sites were sampled during the past (1970-1980) and recent (2000-2010) time periods.

The South Nation River watershed is located in the southwest of Ontario. The sector includes Ottawa and the southern area. It extends in the west to Lower Rideau Lake and to the Ontario-Quebec border in the east. The northern limit is the Outaouais River and the southern limit is the international border. The main hydrogeological feature of the basin is the Vars-Winchester Esker, which is divided in four hydrogeological units, based on the quaternary sediments. These units have two aquifers (one in the glaciofluvial sediments and the other in the bedrock) separated by aquitards (Champlain Sea mud and till). The dataset describes in details the stratigraphy and groundwater usage. However there are also available information on confinement, surficial deposits thickness, hydrogeological unit thickness, recharge and discharge, hydrogeological unit yield, aquifer potential, hydraulic conductivity, and groundwater quality. The dataset is a summary of data and hydrogeological information for all aquifers, aquifer systems and hydrogeological contexts of the South Nation River Basin project.

The Matawa Water Futures (MWF) project was developed through the Global Water Futures project to advance Indigenous-informed water science to support decision-making and water stewardship in the Matawa First Nation (MFN) homelands and traditional territories in Northern Ontario. The objective for the end of the MWF project is to hold a large water-themed gathering, inviting all MFN communities to attend to celebrate the value and sacredness of water, as well as share observations and scientific knowledge about the water, and share progress in water and environmental stewardship programs. A vital piece that has supported this project over the years has been the relationships built within our communities, as well as those relationships built with other nations and organizations. In keeping with this appreciation of fostering and maintaining relationships, we would like to extend an invitation to include Indigenous groups and organizations around Canada and beyond who are working in water and environmental initiatives or programs, overall advancing Indigenous stewardship within their own homelands. This gathering is an opportunity to: Share knowledge and learn from each other about water relationships, values and perspectives, as well as water & environmental stewardship practices and policies; and to Facilitate opportunities for collaboration and relationship-building.

The goal of this carbon cycle study is to: * better understand wetland carbon uptake and losses to the atmosphere across watersheds * evaluate wetland carbon’s usefulness as a natural climate solution Study sites Study sites for this project are: * Big Creek Watershed in Southern Ontario * White River in the experimental forest area in Northern Ontario We chose these sites to represent relatively data-scarce regions of Ontario, and locations that represent: * recently restored wetland * an undisturbed wetland These locations can show how wetlands can act as natural climate solutions. Wetlands and climate change Wetlands absorb and release atmospheric carbon as plants grow and decompose. If wetlands absorb more carbon than they release, they can act as natural climate solutions. Wetland restoration and wetland preservation: * promotes carbon uptake by wetlands in Ontario * slows future climate warming Wetland carbon exchange with the atmosphere varies immensely across space and time. These continuous measurements are used to: * calculate the amount of carbon moving between the air, plants and soils of wetlands * improve numerical models that will help us predict how wetland carbon exchanges might respond to climate warming at these locations and other locations Download the study data We submit this data to Ameriflux, which is a network of sites measuring ecosystem CO2, water and energy fluxes in North, Central and South America. You can download the data from Ameriflux.

This dataset includes one Microsoft Excel spreadsheet file containing soil and sediment chemistry data across different habitats in 4 harvested and 2 unharvested reference forest watersheds in the Dryden area of northwestern Ontario. Data include total mercury concentrations, methylmercury concentrations, mercury methylation potential rate constants, methylmercury degradation potential rate constants, soil water content and bulk density, and carbon and nitrogen content.

The Turkey Lakes Watershed Study (TLWS) was established in 1979 and is one of the longest running ecosystem studies in Canada. It is 10.5 km2 and is located approximately 60 km north of Sault Ste. Marie, Ontario at the northern margin of the Great Lakes – St. Lawrence forest region. Researchers from Natural Resources Canada, Environment Canada and Fisheries and Oceans Canada established the research watershed to evaluate the impacts of acid rain on terrestrial and aquatic ecosystems. Since its inception, the study has taken a multi-disciplinary approach to investigating the processes that govern ecosystem responses to natural and anthropogenic perturbations. The goal of the TLWS is to obtain a whole-ecosystem analysis of the biogeochemical processes operating at the site. This permits system models to be developed and validated. The holistic approach that has been adopted from the outset allows research to evolve and expand from its original acidification focus to include evaluations of other environmental issues. Partnerships and collaboration are part of the founding principles behind the TLWS to improve our ability to measure, model and predict effects of human activity on ecosystem function. Over time, research and monitoring have expanded to explore the effects of forest harvesting, climate change, aquatic habitat manipulations and toxic contaminants. Advancements of our scientific knowledge of forest ecosystems and a baseline of long-term environmental data enables study results to inform Canadian governments on environmental policy and forest management legislation. Hydrological, meteorological, and vegetation data collected by scientists at the Great Lakes Forestry Centre is included in this directory. Experimental sites and scientific investigations in the TLW are summarized in the compendium document. Visit our website at:

This dataset contains all data used for a journal article submission/publication titled "Landscape controls on total mercury and methylmercury export from small boreal forest catchments". This dataset includes approximately bi-weekly observations of stream chemistry parameters and landscape variables for 19 watersheds in the Dryden region of northwestern Ontario.

The Aquatic Habitat Inventory contains lake, river and stream survey data collected from the 1950s to the 1990s. These surveys were conducted to acquire basic knowledge of the chemical, physical and biological characteristics of Ontario’s lakes, rivers, and streams to aid in watershed planning, aquatic habitat conservation and fisheries management.

Bay of Quinte was designated as one of the 43 Areas of Concern in accordance with Great Lakes Water Quality Agreement (GLWQA). Remedial Action Plan (RAP) is an ongoing collaborative effort implemented by federal, provincial, and local governments as well as industry and public partners. There are 3 key stages of the RAP: Stage 1 is a detailed description of the environmental problem; Stage 2 identifies remedial actions and options; Stage 3 is the final document providing evidence that the beneficial uses have been restored and the AOC can be “delisted”. The Bay of Quinte is a narrow inlet, about 100 km in length, on the north shore of Lake Ontario near the eastern outlet of the lake. The Area of Concern encompasses the bay and its 18 000 km2 (1.8 million ha) drainage basin. The watershed includes the generally agricultural Prince Edward County on the south side of the bay and extends as far north as Algonquin Park. The Trent River is responsible for most of the flow through the bay. The shoreline of the bay includes 19 provincially significant wetlands. About 400 000 people live in the area, with the population around the bay concentrated in the cities of Trenton and Belleville, the towns of Napanee, Picton and Deseronto, and the Mohawk Tyendinaga Territory. For more information visit: https://www.canada.ca/en/environment-climate-change/services/great-lakes-protection/areas-concern/bay-of-quinte.html

An Area of Concern (AOC) is a location where environmental quality is degraded compared to other areas in the Great Lake Basin resulting in the impairment of beneficial uses. A total of 43 AOCs were identified as a result of Annex 2 of the Great Lakes Water Quality Agreement (GLWQA).The Canada-United States GLWQA identifies 14 beneficial uses that must be restored in order to remove the designation as an Area of Concern. A beneficial use is defined as the ability of living organisms (including humans) to use the Great Lakes Basin Ecosystem without adverse consequences. A Beneficial Use Impairment (BUI) is a condition that interferes with the enjoyment of a water use. Each BUI has a set of locally-defined delisting criteria that are specific, measurable, achievable, and scientifically-defensible. The Remedial Action Plan (RAP) is administered locally in accordance with the Canada-U.S. Great Lakes Water Quality Agreement (GLWQA) and the Canada-Ontario Agreement (COA). The RAP is an ongoing collaborative effort implemented by federal, provincial, and local governments as well as industry and public partners. There are 3 key stages of the RAP: Stage 1 is a detailed description of the environmental problem; Stage 2 identifies remedial actions and options; Stage 3 is the final document providing evidence that the beneficial uses have been restored and the AOC can be “delisted”. The Toronto and Region Area of Concern extends along the northern shoreline of Lake Ontario from the Rouge River in the east to Etobicoke Creek in the west. The 2000 km2 (200 000 ha) area includes the Toronto waterfront and 6 watersheds: Etobicoke Creek, Mimico Creek, Humber River, Don River, Highland Creek and Rouge River. The drainage basin of these watersheds makes the Area of Concern a study in contrasts: more than 40% of the area is still rural and contains one of the world’s largest natural parks in an urban/agricultural setting; at the same time, more than three million people live in the Area of Concern and the City of Toronto is in the centre of the most densely urbanized area in Canada. The Toronto region was designated as an AOC in 1986 because a review of available data indicated that water quality and environmental health were severely degraded. Several centuries of agriculture and urban development have dramatically reshaped the natural environment of the Toronto and Region AOC. Contaminants from stormwater runoff and melting snow from the area’s six watersheds create serious impacts in Lake Ontario. Overflows of stormwater mixed with raw sewage are a serious problem following heavy rains in the lower portions of the Don and Humber Rivers and along the waterfront. Spills, road runoff and chemical input to sewers from industries and residences also contribute to poor water quality. In the Toronto and Region AOC’s Remedial Action Plan (RAP) report, Clean Waters, Clear Choices: Recommendations for Action (1994) eight beneficial uses were identified as impaired and three were identified as requiring further assessment. For more information visit https://www.canada.ca/en/environment-climate-change/services/great-lakes-protection/areas-concern/toronto-region.html