Table 4.
Kilometers of river by region and within the CONUS that met the criteria of an example query to identify stream reaches with (1) low probability of being good biological condition (Pr(good) < 0.5), (2) low index of catchment integrity (ICI < 0.60; the 1st quartile of national ICI values), (3) high watershed integrity (IWI > 0.75; mean of national IWI values), and (4) either an upstream or downstream adjacent reach with high probability (Pr(good) > 0.5) of being in good biological condition. For headwater streams, the criteria of IWI > 0.75 was ignored because the local catchment and watershed are the same geographic unit and we assumed that restoration of catchments integrity would result in a commensurate increase in IWI. These criteria can be adjusted to be more or less inclusive to refine a list of candidate streams. National Aquatic Resource Surveys (NARS) region abbreviations: CPL = Coastal Plains; NAP = Northern Appalachians; NPL = Northern Plains; SAP = Southern Appalachians; SPL = Southern Plains; TPL = Temperate Plains; UMW = Upper Midwest; WMT = Western Mountains; XER = Xeric.
| NARS Region | Km of River |
|---|---|
| CPL | 8.5 |
| NAP | 179 |
| NPL | 39 |
| SAP | 1,983 |
| SPL | 116 |
| TPL | 4,659 |
| UMW | 235 |
| WMT | 4 |
| XER | 197 |
| CONUS | 7,331 |