Natural resource systems are summarized into five ecological components: biology, connectivity, hydrology, water quality and geomorphology. A number of different index scores are calculated for each component giving a multifaceted view of watershed health.
Health scores rank the condition of Minnesota's landscapes from 0 (poor health condition, red) to 100 (good health condition, green). This example shows remaining perennial cover.
Health scores are calculated for Minnesota's "major watersheds" (HUC-8), and where possible for DNR catchments (HUC-12). Catchments are much smaller units and provide more detailed view of the health scores. In Minnesota there are 81 "Major Watersheds" and over 10,000 catchments.
Clicking on any of the five components on the left side bar opens the various indices of which it consists. Click on each index to view the results on the map. Click on another index to view different results for the same map view.
You can use the transparecy slider to see land features under the score colors. You can also add or remove features from the map under the "Add Feature" tab.
Select a "major watershed" to highlight its boundaries, or use the upstream tool () to see the "true watershed" for your map location. Add "major streams" feature to the map to see flow direction, and click the Minnesota state icon to return to a full state view.
The back and forward buttons ( and ) keep track of your map views, and you can look up places in the search bar on the top left.
The term ‘watershed’ is used in many ways. A ‘True Watershed’ contains the total land area and water features upstream of a given point on the landscape. By contrast, ‘Major Watersheds’ are administrative units (HUC8) that may artificially divide a larger watershed or major river basin. In Minnesota, more than half of the Major Watersheds are not true watersheds.
When exploring the WHAF Map, DNR Catchments are used as the smallest delineated unit of drainage area. Use the Upstream Tool to highlight a catchment and see the other catchments that contribute to create its true watershed.
Watershed Health Assessment Scores were calculated at the level of ‘Major Watershed’ and, where possible, ‘DNR Catchment’. Proper exploration should include using the upstream tool to explore the relationship between true watersheds, administrative watersheds and other natural and artificial boundaries.