Data are contaminants in tissue of caged mussels put in the river for 3 weeks at about 25 stations located on the Canadian and US side of the river. The main objective of the study is to identify contaminant sources, or source areas requiring more detailed follow-up investigations, based on the level  of contaminants in the mussels. Compounds monitored include: * organochlorinated pesticides * Polychlorinated biphenyls * dioxins/furan * chlorinated benzenes * Polycyclic aromatic hydrocarbons * industrial organic compounds

The Standardized Precipitation Index (SPI) was generated for certain Environment Canada long-term climate stations in Ontario. The SPI quantifies the precipitation deficit and surplus for multiple time scales , including: * one month * three months * six months * nine months * 12 months * 24 months You can use the SPI to study the impact of dry and wet weather conditions to create comprehensive water management approaches. The SPI data package is distributed as a Microsoft Access Geodatabase. __This is a legacy dataset that we no longer maintain or support.__ The documents referenced in this record may contain URLs (links) that were valid when published, but now link to sites or pages that no longer exist.

These maps are available for the Far North Land Use Planning Area at 2 scales (1:100,000 and 1:250,000). The maps were created as a resource for community-based Land Use Planning in the Far North of Ontario.

The Ontario Point Cloud (Lidar-Derived) consists of points containing elevation and intensity information derived from returns collected by an airborne topographic lidar sensor. The point cloud is structured into non-overlapping 1 km by 1 km tiles in LAZ format. The following classification codes are applied to the data: * unclassified * ground * water * high noise * low noise This dataset is a compilation of lidar data from multiple acquisition projects, so specifications, parameters, accuracy and sensors may vary by project. This data is for geospatial tech specialists, and is used by government, municipalities, conservation authorities and the private sector for land use planning and environmental analysis. __Related data:__ Raster derivatives have been created from the point clouds. These products may meet your needs and are available for direct download. For a representation of bare earth, see the [Ontario Digital Terrain Model (Lidar-Derived)]( https://geohub.lio.gov.on.ca/maps/mnrf::ontario-digital-terrain-model-lidar-derived/about). For a model representing all surface features, see the [Ontario Digital Surface Model (Lidar-Derived)](https://geohub.lio.gov.on.ca/maps/mnrf::ontario-digital-surface-model-lidar-derived/about).

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. The shapefiles available for download outline the outer boundaries for: * the Northwest GTA Transmission Corridor Identification Study area, announced in June 2019 * the Northwest GTA Transmission Corridor Narrowed Area of Interest, announced in September 2019 * The Northwest GTA Transmission Corridor 2020 Narrowed Area of Interest, announced in November 2020 * The Northwest GTA Transmission Corridor 2024 Narrowed Area of Interest, announced in November 2024

This Ontario Hydro Network (OHN) small scale dataset is intended for cartographic and web mapping display purposes, not for analytical work. Small scale waterbody, watercourse and shoreline data is available at the following seven scales: * 1:100,000 * 1:200,000 * 1:500,000 * 1:1,000,000 * 1:2,000,000 * 1:5,000,000 * 1:10,000,000 Search the [Land Information Ontario (LIO) Warehouse OHN Products Composite File Geodatabase](https://geohub.lio.gov.on.ca/datasets/land-information-ontario-lio-warehouse-ontario-hydro-network-ohn-products-composite-file-geodatabase) to download a file geodatabase of all the OHN’s publicly available (Open) derivative cartographic products taken from the LIO Warehouse on a bi-weekly basis.

The Ontario Digital Surface Model (Imagery-Derived) is a raster elevation product that was generated from the elevation point clouds created via pixel-correlation from aerial photography. A DSM is the highest reflective surface of features captured by the sensor. This surface is also referred to as the first reflective surface. The DSM may include: * treetops * rooftops and tops of towers * telephone poles * other natural or artificial features * ground surface if there is no vegetative ground cover This data is for geospatial tech specialists, and is used by government, municipalities, conservation authorities and the private sector for land use planning and environmental analysis.

The Ontario Watershed Information Tool (OWIT) is used to calculate information about Ontario’s watersheds. Watersheds are areas of land where surface water converges to a single point. Water professionals in the public and private sectors and academia use OWIT to better understand water flow in Ontario. The general public use OWIT for educational or general interest purposes. You can use the tool to: * create a map of a watershed * characterize the watershed * extract land cover information

The Ontario Lidar Digital Terrain Model (DTM) Land Information Ontario (LIO) Dataset is a raster product representing the bare-earth terrain derived from a classified lidar point cloud. The DTM data is available in the form of 1-km by 1-km non-overlapping tiles grouped into packages for download. This dataset is a compilation of lidar data from multiple acquisition projects, as such specifications, parameters and sensors may vary by project. This data is for geospatial tech specialists, and is used by government, municipalities, conservation authorities and the private sector for land use planning and environmental analysis.

The LIO Topographic Data Cache is a collection of topographic data, that has been preprocessed for fast, seamless display at predefined scales. The topographic data includes constructed and natural features that make up Ontario’s landscape. The cache provides limited data from areas outside Ontario’s boundaries, such as the United States and adjacent provinces and territories. __Technical information__ Two versions of the LIO Topographic Data Cache are available: 1. The traditional raster version is available for a variety of GIS applications and is updated annually. 2. The vector version is suitable for online web map applications as well as modern GIS software and is updated twice a year. Contributing data layers may have different maintenance and update cycles. Some cache layers have been processed in a way that makes it easier for them to be displayed in a mapping product. Other layers are unchanged from the authoritative data. The cartographic symbology used in the data cache is intentionally muted to allow users to showcase their data. The LIO Topographic Data Cache is created from many source datasets, which are described in the LIO Topographic Data Cache user guide. If you are interested in getting this authoritative data, you can download it from the [Ontario GeoHub](http://www.ontario.ca/geohub). For instructions on getting a copy of either version of the cache for use in mapping applications, visit the [Ontario GeoHub](http://www.ontario.ca/geohub).