Common St. Dam

A small tube chute in the middle of this low-head dam funnels the water toward the middle of the river, which is the usual line for running the rapid.

The dam forms a surfable wave at flows as low as 400-450 cfs, with a small pool deep enough to roll in.  However, the riverbed just downstream of the pool is very shallow at that level, so you need a quick roll in order to avoid hitting your head if you flip over.  As the flow increases toward about 800-850 cfs, the wave becomes narrower but taller and without the downstream headache potential.  It washes out at flows above this and does not reform until the flow reaches thousands of cfs.

At thousands of cfs, Common St. Dam forms a ledge hole at river right.  At 3000-3500 cfs, this hole is very grabby, with significant recirculation on the downstream side-- not a very friendly place to play.  At 4000-4500 cfs, it is still grabby but much more friendly, and at that level, it is a prime place to practice loops and other vertical tricks.  At 5000-6000 cfs, the river right ledge hole becomes more of a friendly wave-hole that is mostly front-surfable.  It still gives up loops, but not as easily as at lower levels.  At high flows, the river right eddy service is excellent.  At above 5k, the eddy at far river right actually extends above the feature.

At 5000-6000 cfs, a large wave-hole forms at river left, wide enough for five boats to surf simultaneously.  River left eddy service at these levels is tricky at best.

Since the bridge pilings are only about 60' downstream of the dam, a solid roll is strongly recommended if you plan to play here.

Technically the park at river left before the bridge is private (apparently part of the subdivision), so don't hang out there for too long unless you're in the water.  The park at river left on the downstream side of the bridge is public.