Comments:
Within Segment C, Fayville Branch transitions from bedrock channel upstream toward downstream confluence with Warm Brook. Topographic contours suggest alluvial fan type of feature at this transition from semiconfined valley to Very Broad valley and a decrease in slope from 2.8% in upstream segment T2S1S1.02-A to 1.8% in T2S1S1.01-C (and 0.9% in Segm B, 0.5% in Segm A). Two channel-spanning exposures of bedrock ("waterfall") were observed in the segment. Upstream-most exposure is actually the base of the grist mill falls; technically, this waterfall would be grouped with the upstream segment of bedrock channel; however, it was indexed within this segment T2S1S1.01-C due to a slightly mis-located Phase 1 reach break. Old Mill Rd in RB corridor and Pleasant St in LB corridor are slightly elevated above the surrounding floodplain, and therefore resulted in a slight human-caused change in valley width (St 1.5) - enough to change the valley type (from Very Broad to Broad), but not sufficient to change the confinement type (unconfined). Floodplain along both sides of the channel is developed with residential, municipal, and commercial buildings (village of East Arlington). Development is historic dating back to the mid- to late-1700s (Child, 1880) and once included the Judson & Billings factory (Beers, 1869). Channel margins have likely been graded and reworked during historical development and during recovery from past flood events. Streambanks have been heavily armored with rip-rap and incorporate building foundations as "hard bank" armoring along the RB. Short section of berm is present along LB downstream of grist mill waterfall. Trees incorporated in the streambank armoring provide further bank protection. Channel is partly incised below the floodplain. Ice Pond Rd crosses the channel mid-segment via a bridge with concrete wing walls; bridge has a bankfull-constricting span and aggradation is noted at the bridge inlet. Stormwater runoff occurs directly from paved parking area along RB upstream of the bridge and through urban stormwater pipes along RB.