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I I I I I I I I I I I I I- I I I I I I 13 -;f- channel crossings, which consist ~f-br~dgeS~CUlve~nd pipe- lines, if not properly engineered will collect debris and create backwater conditions which will cause water levels to rise to the extent that more land is inundated by flood waters. , , "Erosion problems also will arise when the natural flow of the river is obstructed and narrowly confined. The strength capa- bility of the bridges and culverts can sometimes be exceeded and the crossing may be destroyed, creating further debris and headwater flowing in the channel and flood plain. Other obstructions in the flood plain such as buildings, commercial and residential, also create additional flood hazards. Structures in the flood plain restrict flood flows and reduce the carrying capacity of the natural flood plain. ConsequentlY't ,-/e tV "~v...,, v.-t'" e<11. ... backwater effects occur and ,result in increased velocities of I~,~ flow at release points and flooding o~_~npr~dictable,areas. The major feature in the Breckenridge area that contrib- utes to a reduction in flood damage is the Goose Pasture Tarn Reservoir. The reservoir is located immediately upstream of the town of Breckenridge. The reservoir has a drainage area - of approximately 43.5 square miles. The maximum storage capacity of the reservoir is 30,000 acre-feet and a spillway design capacity of 5,000 cfs. Through the process of storing and gradually releasing flood waters from the tributaries contributing to the reservoir, the reservoir reduces the peak discharge of the Blue River pricrto its entering the town of Breckenridge. The Goose Pasture Tarn Reservoir is owned by the Blue River Water District and is used primarily for "- recreation, although the reservoir also serves as a water supply for Breckenridge. Other smaller lakes are located on the Blue River both within the town and in the tributaries, but these lakes are small and have, for all practical purposes, no storage area and therefore would not affect flood flows. The smaller lakes would act more as a channel section of increased width which would pass the peak discharge immediately downstream.