150 cfs is low but enough, for put at either Ponca or Steel Creek. (roughly 24 inch air gap at Ponca bridge.)
Between 15 and 20 inches of air gap at Ponca bridge may be optimum for put in at either Ponca or Steel Creek
4/19/14 - -21 inch gap and 230 cfs, Redbuds and Dogwoods in full bloom, very few leaves out, levels holding much better than after trees get all leaves out. Really nice level for Steel Creek to Kyles. Some rock dodging is necessary. Lots of gentle eddys and waves to play with, enough depth everywhere but requires reading the features and some easy manuevering to get on line. Good example is at Lick Ford where the normal diagonal line from right to left is narrow, but nearly straight, dry line with minor cross currents. Many nice, smooth waves in Grey Rock Shoals, several with very easy access. Also, the jet of current immediately below Steel Creek put in and mouth of Steel Creek in the left bend of river is strong enough for self evaluation. Those who can forward ferry back and forth across that current, are likely able to manuever most of what will be encountered in this section, if not be prepared for pins and swims.
Trip Leaders Note: Be careful about what paddlers say or think they can do. Actually doing a few ferries speaks with much more authority than talking about how long they have paddled or how high the water was. L4 Demonstration Quality of ferries would have aggressive, stable leans, only one or two strokes, quite blade, and all in both forward and reverse.
3/9/12 --18 inch gap and 350 cfs is an excellent level. From Steel Creek down mid channel rocks covered, nice waves in the several places.
6/4/13 --17 inch gap and 420 cfs, many rocks covered, most shoals are wide open, several have nice waves. Lick Ford is very active at this level, some rocks just peaking out of the waves, others just under and grabbing careless boats. Current is fast in several places can push boats into trees, branches, and snags.
3/13/12 -- maybe 8-10 inch gap, 720 cfs. The river at this level will deceive many people. The rocks are covered and most shoals are wide open and have on minimum waves , example - Lick Ford was washed out and a non-event. However, pools are beginning to move, current in many places is fast and has unexpected power, some eddies pretty active with boils and whirlpools. On this trip, I was involved in two situatiions outside our group where boats had been flipped and children separated from parent. One went far downstream and out of site while father and boat caught in a small, strong eddy. Second was teenager thrown from a rec kayak which was lost downstream and the boy left on wrong bank with swift water between him and parent. In our own group, two different kayakers had multiple swims, all in eddies that either weren't seen, understood, nor anticipated.
About 1600 cfs, is zero air gap at the old Ponca Bridge, and a lot of water. NPS will close access as the river rises to this level.
Be especially wary when the river is rising, when the current has floating debris, and when there is possibility of rain storms upsteam.
See also Buffalo Outdoor Center Visual reading at Ponca and probably the best, daily interpretation of this part of the river. BOC is reliable source for information, advice, maps, and books for the whole Buffalo River although they operate on the upper half of the river.
Best reference book for floating, hiking and general information of the river is "Buffalo River Handbook" by Kenneth L Smith and is coordinated with Trails Illustrated Topographic Maps/ East Half from Woolum downstream and West Half from headwater to Woolum.
Use this NPS Guide of Buffalo River Levels with care NPS uses 2000 cfs as flood at Ponca, but upsteam at Boxley is not labeled as flood until it reaches 6500 CFS. While quite possible that this is technically correct, it could be a very dangerous mis-interpertation of actual conditions not far from the gage. Typically flow at Ponca is nearlty double that at Boxley.
At higher flows (maybe? 600+ cfs) the Ponca to Kyles section of the Buffalo River has some of the short runs of Class 2 Whitewater. Class 2 does not mean "safe", "easy", or "No Consequence". Boats can be lost, pinned on trees, root balls or strainers. or flipped by waves. As flow increases, even the pools are moving and safe eddies are smaller and harder to find.
Class 2 does mean that clear channels are visible without scouting, some maneuvering in fast current is needed to avoid the various hazards, and self rescue is possible.
Swimmers in fast current usually do get banged up, cut up, and bruised. Pot holes and strainers in the river's rock bed are present in places and can be very dangerous.