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I I I I I I I I I I I I I I I I I I I - 33 - The table below lists the recommended under clearance for each of the crossing structures through the town of Breckenridge: TABLE 6 Minimum Bridgel Under-Clearance Elevations Structure Broken Lance Road (U/S) Broken Lance Road (D/S) Village Road2 Adams Road (new) Lincoln Avenue Watson Road Cemetery Road Elev. 9667.3 9642.5 9605.8 9587.8 9666.5 9547.0 9652.0 1) 2 ft. freeboard over IRF flood elevation 2) New bridge should be combined with drop structure to reduce downstream erosion potential CHANNEL There is only one area of the channel that is seriously in need of strengthening and enlargement. This is in the reach between Village and Lincoln near the existing pedestrian bridge crossing. The east bank should be constructed at least 2 to 3 feet higher so that flows are contained within the channel. This can be accomplished by taking some material from the west bank and placing it on the east side and providing armoring of adequate sized rocks along the channel. The channel throughout the town is steep and the high velocities which may occur during an IRF flood will cause some erosion. The material is predominantly rock and the smaller will be transported along the banks from one point to another. The larger rock will be able to withstand the erosion. Ideally, the entire channel ~hould be widened, strengthened and the slope flattened to reduce the flood velocities through the town. This would require the construction of drop structures, some which could be incorporated into the new bridge crossings. Such a program would be costly and, depending upon future de- velopment plans adjacent to the stream bank, may not be required. The channel immediately below the village Road crossing is very steep. When the Village Road culverts are replaced with a bridge ~ Leonard Rice Consulting Water Engineers. Inc.