Comments:
Updated Dec 2008, relying primarily on field observations and additional cross sections collected in Sept 2008 to support original October 2004 assessment. Upper half of subreach of E-dune/ripple reference stream type, that has undergone substantial channelization. Cut off meanders can be seen on either side of the straightened channel on the 1999 orthophotograph. Wetlands (NWI) and hydric soils are mapped contiguous to the channel. Pasture has recently been established in previously fallow fields within 25 ft of the LB. Fallow fields are present along RB corridor. A farm road culvert crossing is present near the downstream end of the segment. Weak riffle/pool bedform is present where a reference dune/ripple form might be expected in a channel that was highly sinuous prior to channelization. Riffles are short in length; often riffles are sedimented (i.e., diagonal). Occasional short lengths of rip-rap (rounded field stone) were observed along RB adjacent to now fallow fields. One RB tile drain observed. Farm road instream culvert is bankfull constrictor and scour pools are present upstream and downstream of this structure. Dredging is inferred to have accompanied historic channelization. E dune/ripple reference stream type is inferred from narrow / deep channel, high (pre-channelized) sinuosity visible on 1999 orthophoto, and cohesive soils. The W/D ratio (16.5) suggests that an E to C lateral stream type departure has occurred.