Watershed boundary delineated for Canada-BC hydrometric stations. Currently, watersheds were delineated using 1:50,000 scale boundaries in 1996, and many watersheds encompass entire drainages, instead of just the upstream watersheds. Note - Not yet available, but we are in the process of generating BC hydrometric station upstream watersheds using updated base data, using the following method: Within BC, watershed boundaries are based on the 1:20,000-scale Freshwater Atlas fundamental watersheds, and trimmed using the BC TRIM DEM used to approximate the height-of-land at the station locations. Outside of BC, but within Canada, watershed boundaries were approximated using Canada CDED DEM data for delineation (no "stream burning" was used) and some manual editing of boundaries was done to approximately match hydrology data after the fact. Within U.S.A., the USGS Watershed Boundary Dataset was used (at the best scale available for each drainage) to delineate the watershed boundary, with the watershed trimmed using the USGS National Elevation Dataset to approximate the height-of-land when necessary.

Zones that represent areas of homogeneous hydrologic and geomorphological characteristics

The “Hydrometric Gauging Station Network of the AAFC Watersheds Project - 2013” dataset is a geospatial data layer containing network line features representing links between hydrometric gauging stations of the Agriculture and Agri-Food Canada (AAFC) Watersheds Project. Each line connects a gauging station to its downstream neighbour(s), indicating its drainage direction.This network is a ‘drainage’ network, not a ‘stream’ network. That is, the lines do not in any way portray the actual stream path between stations.In some instances, a lake, for example, an area may have several gauging stations. In such cases, one of the gauging stations is designated the ‘primary’ gauging station for calculation purposes, and to maintain proper hydraulic relationships between gauging stations, where only the primary stations are connected to the downstream portion of the network.

The “Sub-basins of the AAFC Watersheds Project – 2013” dataset is a geospatial data layer containing polygon features representing the Standard Drainage Area Classification (SDAC) 2003 defined sub-drainages of the Agriculture and Agri-Food Canada (AAFC) Watersheds Project. Canada has eleven major drainage areas which are divided into 164 sub-drainage areas. All drainage areas and sub-drainage areas are named and have an identifying ‘number’. Sub-drainage areas have ‘numbers’ that share a common ‘three-character’ designation. For example, the 05A sub-basin contains stations ‘numbered’ 05AB006 and 05AC007.

The "Hydrometric Gauging Stations of the AAFC Watersheds Project - 2013" dataset is a geospatial data layer containing point features representing the hydrometric gauging stations of the Agriculture and Agri-Food Canada (AAFC) Watersheds Project. The gauging stations are sourced from Environment Canada, the United States and Canadian provinces. Additional virtual stations have been generated to address hydrometric structural issues, like river confluences or lake inlets. Attribute information includes station identification, location and associated catchments/basins.

The “Gross and Effective Drainage Area Boundaries of the AAFC Watersheds Project - 2013” dataset is a geospatial data layer containing line features representing boundaries associated with the ‘incremental gross drainage areas’ of the Agriculture and Agri-Food Canada (AAFC) Watersheds Project. The project is subdivided by hydrometric gauging station. The maximum area that could contribute runoff to each station, less that of its upstream neighbour(s) is called its ‘incremental gross drainage area’. Two types of boundary are provided: ‘gross’ and ‘effective’. ‘Gross’ boundaries separate adjacent incremental gross drainage areas. ‘Effective’ boundaries delimit, within each incremental gross drainage area, the separation between areas that supply runoff, based on average runoff, from those that don’t.

The “Incremental Gross Drainage Areas of the AAFC Watersheds Project - 2013” dataset is a geospatial data layer containing polygon features representing the incremental gross drainage areas of the Agriculture and Agri-Food Canada (AAFC) Watersheds Project. The Project area is subdivided by hydrometric gauging station. The maximum area that could contribute runoff to each station, less that of its upstream neighbour(s) is called an ‘incremental gross drainage area’.

The “Major Drainage Systems of the AAFC Watersheds Project - 2013” dataset is a geospatial data layer containing polygon features representing the three (3) major drainage system basins of the Agriculture and Agri-Food Canada (AAFC) Watersheds Project. The Project area has been split according into which body of water it drains: the Arctic Ocean, Hudson Bay or Gulf of Mexico.

The “Major Basins of the AAFC Watersheds Project - 2013” dataset is a geospatial data layer containing polygon features representing the 23 major basins of the Agriculture and Agri-Food Canada (AAFC) Watersheds Project. The Project is subdivided by ‘incremental gross drainage areas’ associated to individual hydrometric gauging stations. The maximum area that could contribute runoff to each gauging station, less that of its upstream neighbour(s) is called an ‘incremental gross drainage area’. Conceptually, the major basins are collections of the “incremental gross drainage areas” associated with particular major river or lake reach (for example, reaches of the Saskatchewan or Athabasca River). In practice, each major basin consists of the collection of incremental gross drainage areas, whose gauging stations’ numbers have collections of the same three first characters. For example, the Assiniboine River major basin contains the incremental gross drainage areas whose gauging station numbers start with 05J, 05M, or 05N.

Zones of homogeneous low flow characteristics