It's never too low for the MD Lines. Below 2.6' is ELF, but there are runnable channels at least down to 2.4', and most summers the river never gets that low. So when everyone else is whining about the drought, you still have a class V playground in your backyard. Count your blessings. I'd say 2.6' to 2.7' is a good first time level. Above 2.8' the holes get mean, and above 3.0' they're vicious. The MD Lines can certainly be run higher than 3.1', but if you're considering it you don't need this guide.
The gage is located at Little Falls (aka Brookmont) Dam, where the river is very wide. Consequently, an inch on the gage can translate to a foot at Great Falls. The gage is also 8-9 miles downstream, so if the river is rising or falling rapidly there could be a discrepancy between the gage reading and the actual level. Scout the rapids visually if there is any doubt. (You were going to do that anyway, right?)
USGS Potomac River / Little Falls Gage
NOAA Prediction for Little Falls Gage
| Name | Range | Difficulty | Updated | Level | ||||||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| POTOMAC RIVER NEAR WASH, DC LITTLE FALLS PUMP STA | ||||||||||||||||||||||||||||
| usgs-01646500 | 2.00 - 3.50 ft | V+ | 00h43m | 3.9 ft (rc= 1.6 ) | ||||||||||||||||||||||||
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