Patapsco, South Branch

For a minimum level, look at three gauges: Hollofield 500 cfs; Cedarhurst 150 cfs; Unity 90 cfs. Hollofield is well downstream on the Patapsco Mainstem, so it can still be up when water's drained out of the S. Br. Patapsco, but it is a good reflection of the watershed as a whole; Cedarhurst and Unity are on parallel watersheds about the same amount upstream, so they can give some idea of 'top of the watershed' conditions. Because the S.Br. Patapsco is so flashy, you need to be aware that water can run out from the night before to the morning of the run. I don't know what a maximum level might be, but I would suggest that you go to the downtown Sykesville bridge and look at the river. If your reaction is FUN!, run it; if your reaction is 'Oh My God' it's too high.