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DRAFT three feet. In the area of the Park Avenue bridge, flood levels for this study are approximately three feet higher than the FEMA study. This is due partially to the bridge construction and associated channel work. In the FEMA study, 220 cfs followed a side channel to the west, after construction of the Park Avenue bridge, this overflow channel on the east bank was cutoff and the entire flow confined to the main channel. However, some of the increase may be due to the limited number of cross sections used in the FEMA study. The profile between cross sections is interpolated as a straight line which can cause considerable inaccuracies on a steep channel if grade breaks exist between the cross-sections. Between French street and Watson street there is a short section where the FEMA levels are about 2 feet lower than this study. The topographic mapping from the two studies differs here. There may have been some fill placed along the east bank that has encroached upon the channel. Downstream of the Watson street bridge for 100 feet, this study's water surface levels are lower due to a lowering of the river bed as a result of local scour downstream of the culverts. upstream of the bridge the current flood levels are lower because the previous single 6' CMP culvert was replaced with two 8' CMP culverts. The flood levels have been raised on the order of one to two feet downstream of Ski Hill Road due to encroachment by development along the west bank. The bed was not raised, however, the channel width has been reduced by fill and placement of boulders. Between Ski Hill Road and the Skelly pond, the flood levels agree within one foot of each other. The levels in the Skelly pond are about one foot higher in the FEMA study. The variation is due to differences in the cross-sections. Between the pond and the Park Ave. crossing, the current study shows elevation one to three feet lower than FEMA. This is due mostly to differences in cross- sectional surveys. The FEMA study did not account for the steep drop immediately downstream of the culverts. Upstream of Park Ave., the Village, was constructed between the time of the FEMA study and this study. Several changes have occurred due to the development. Immediately above Park Ave. the levels agree. For a short distance above the Village bridge the levels are currently 1.5 feet higher. The biggest change is that the flood levels in the Maggie Pond have been lowered by two to three feet due to lowering the pond spillway. Above the Village, there is considerable disagreement between the two studies. The discrepancy is due to differences in cross- sectional surveys. It appears that, the flood study cross-sections were developed from topographic mapping and not field surveys. 36