Hydrography (HY) Iceland is one of 12 themes in the European Location Project (ELF). The purpose of ELF is to create harmonised cross-border, cross-theme and cross-resolution pan-European reference data from national contributions. The goal is to provide INSPIRE-compliant data for Europe. A description of the ELF (European Location Project) is here: http://www.elfproject.eu/content/overview Encoding: INSPIRE version 4

This layer represents the watershed areas that report to Water Survey of Canada (WSC) and United States Geological Survey (USGS) gauge stations that meet the following criteria for inclusion: at least 10 years or data (with 350 or more days of observations) above the low outlier threshold; less than 20% (by basin drainage area) regulation; a corresponding basin polygon dataset (either supplied or delineated) with a area <15% different than the basin area reported by WSC or USGS; full metadata coverage for the basin (e.g. mean annual precipitation, elevation, etc.); and 1-, 3-, 5-, and -10 day distribution fits that did not overlap for any Average Recurrence Interval’s (ARI) above 2 years. See Bulletin 2020-1-RFFA British Columbia Extreme Flood Project – Regional Flood Frequency Analysis – Technical development report and manual to complete a regional flood frequency analysis.

This layer represents Water Survey of Canada (WSC) and United States Geological Survey (USGS) gauge stations that meet the following criteria for inclusion: at least 10 years or data (with 350 or more days of observations) above the low outlier threshold; less than 20% (by basin drainage area) regulation; a corresponding basin polygon dataset (either supplied or delineated) with a area <15% different than the basin area reported by WSC or USGS; full metadata coverage for the basin (e.g. mean annual precipitation, elevation, etc.); and 1-, 3-, 5-, and -10 day distribution fits that did not overlap for any Average Recurrence Interval’s (ARI) above 2 years. See Bulletin 2020-1-RFFA British Columbia Extreme Flood Project – Regional Flood Frequency Analysis – Technical development report and manual to complete a regional flood frequency analysis.

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.

Existing flood protection works appurtenances on or near dikes, for example, pump house, floodbox, culvert, gate, gauge, weir, etc. Updated from available Provincial dike survey project data from 2019/2020. If 2019/2020 dike survey project data is unavailable, appurtenance data based on previous data from 2004 and prior. May include periodic updates depending on data provided by Diking Authorities and other sources. See Data Source under selected appurtenance for details. For more information on dike management and safety, please see: https://www2.gov.bc.ca/gov/content/environment/air-land-water/water/drought-flooding-dikes-dams/integrated-flood-hazard-management/dike-management For contact names regarding regional diking issues, please see: https://www2.gov.bc.ca/assets/gov/environment/air-land-water/water/integrated-flood-hazard-mgmt/dike_safety_program_contact_list.pdf

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.

Figure 4 12 Diatom groups from Self Organizing Maps (SOMs) in lake top sediments, showing the geographical distribution of each group (with colors representing different SOM groups). State of the Arctic Freshwater Biodiversity Report - Chapter 4 - Page 39 - Figure 4-12

The “Incremental Effective Drainage Areas of the AAFC Watersheds Project– 2013” dataset is a geospatial data layer containing polygon features representing the portions of each incremental gross drainage area of the Agriculture and Agri-Food Canada (AAFC) Watersheds Project that could be expected to contribute to surface runoff under average runoff conditions. An ‘incremental gross drainage area’ is a hydrometric gauging station's drainage basin, less that of the next upstream gauging station(s)’. ‘Effective drainage’ occurs in areas that are expected to supply surface runoff in an average runoff.

10 year peak flow isolines in cubic metres per second (m3/s) for 100 square kilometre watersheds and 10 year return period

Figure 4-7 Circumpolar assessment of lake diatoms, indicating (a) the location of lake diatom stations, underlain by circumpolar ecoregions; (b) ecoregions with many lake diatom stations, colored on the basis of alpha diversity rarefied to 40 stations; (c) all ecoregions with lake diatom stations, colored on the basis of alpha diversity rarefied to 10 stations; (d) ecoregions with at least two stations in a hydrobasin, colored on the basis of the dominant component of beta diversity (i.e. species turnover, nestedness, approximately equal contribution, or no diversity) when averaged across hydrobasins in each ecoregio. State of the Arctic Freshwater Biodiversity Report - Chapter 4 - Page 35 - Figure 4-7