subset_HB_NelR_AtlCda_1M <p>This dataset is a subset of the Standard Drainage Area Classification (SDAC) 2003 dataset. It has been subset to the Nelson River drainage area. These sub-sub drainage areas are part of the Standard Drainage Area Classification (SDAC) which was developed by Natural Resources Canada, in partnership with Statistics Canada, and Environment and Climate Change Canada.</p> <p>A drainage area, as opposed to a drainage basin or watershed, is a unit of statistical aggregation used for reporting purposes based upon drainage patterns and the underlying basins, delimited by a drainage divide. A drainage basin, sometimes called a watershed, is an area where all surface water shares the same drainage outlet. Surface water consists of water flowing on the surface of the earth that develops into larger streams and eventually combines to form a river. The 11 MDAs presented in this map comprise the uppermost level in the drainage area classification system which then divides into 164 sub-drainage areas, and then is further divided into 974 sub-sub-drainage areas.</p> <p>The Drainage Areas dataset is largely based on the Water Survey of Canada (WSC) drainage area boundaries at the sub-sub-basin level. The data model supports the derivation, from the Fundamental Drainage Areas (FDA) dataset (sub-sub-basin level), of the WSC and the National Atlas of Canada (NA) (AC) drainage area hierarchies and the data is available in all three schemes. Drainage area definitions for both WSC and Atlas of Canada boundaries were reviewed resulting in some modifications. Larger scale reference data sources were used for further manual boundary adjustments. This dataset has been integrated with other National Scale Frameworks hydrology datasets and is considered a component of the Hydrology Theme.</p> Drainage Area Environment Hydrography Inland waters Water features Watershed EPSG:4269 -117.4197841600475 -89.86504992465778 45.475509628871066 59.534814489770596 text/xml