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I I I I I I I I I I I I I I I I I I I 2. The existing storm sewer has an approximate capacity of a 2-year runoff event. Existing inlets to the storm sewer frequently became plugged which prevented the storm sewer from reaching its maximum capacity. Therefore, for the purpose of this study, all flood flows were assumed to be on the surface with the major flow paths being Jackson and Ford Streets. The approximate alignment of the existing storm sewer is shown on Sheets 8 and g. the Golden High School property. Upstream of the High School, the area is primarily undeveloped, with the exception of one residential property along Triburary No. 1 downstream of Highway #6. The following tributary streams to the West Fork Kenneys Run were also studied: . Tributary No. 1 (Cross section No.s 301 to 315). This tributary stream begins at its confluence with the West Fork (Cross section No. 133) downstream of U.S. Highway #6 and ends 3480 feet upstream of the highway. Floodplain limits and water surface profiles are shown on Sheets 11 and 15. 3. A shallow flooding area has been designated for an area along Jackson Street immediately downstream of 15th Street (Sheet 9). This designation represents an area where flows become hydraulically disconnected from the main floodplain. The approximate delineation indicates that flows will return to the major water course downstream of 14th Street. Some flow will likely continue down Jackson to the north but should not present a major flood hazard. . North Fork Tributary No.1 (Cross section No.s 401 to 409). This tributary to Tributary No. 1 has its confluence at Cross section No. 307 approximately 860 feet upstream of U.S. Highway #6. The study length of this tributary is approximately 3000 feet. Floodplain limits and water surface profiles are shown on Sheet 14. . Deadman Gulch (Cross section Nos. 501 to 514). This stream has its confluence with the West Fork at Cross section No. 145, approximately 1540 feet upstream ~f U.S. Highway #6. Deadman Gulch has a study reach length of approximately 1100 feet. Floodplain limits and water surface profiles are shown on Sheet 16. . Tributary No.2 (Cross section Nos. 600 to 610). This stream has its confluence with the West Fork at Cross section No. 152, approximately 1500 feet upstream of the Deadman Gulch confluence. Tributary No.2 has a study reach length of approximately 2850 feet. Floodplain 1 imits and water surface profiles are shown on Sheets 13 and 17. West Fork Kenneys Run: West Fork Kenneys Run is considered the primary extension of the main stem of Kenneys Run. This study reach begins at its confluence with the main stem at 20th Street (Cross section No. 111) and ends 4850 feet upstream of U.S. Highway #6 at cross section No. 158. Floodplain limits and water surface profiles for this reach are shown on Sheets 9 through 13. A full-size plan drawing (Sheet 20) was used to ShOW the wider floodplain limits from 24th Street to upstream of the Welch Ditch crossing. Cross sections 115 through 129 are shown on this drawing. Stormwaters enter the downstream storm sewer system at the intersection of Jackson and 20th Streets. Major stream crossings in the reach included 23rd Street, 24th Street, a private road crossing downstream of the Tributary No. 1 confluence, U.S. Highway #6 and other private road crossings west of Highway #6. The Welch Ditch also intersects the drainageway in this reach (Sheets 11 and 20) . The following is a description of flooding characteristics and problem areas along West Fork Kenneys Run: 1. The entrance to the storm sewer system at 20th Street has limited capacity and blockage of this entrance is a common occurrence. The channel upstream from this point has dense growth of trees and brush which contribute to the debris problem. The drainageway traverses through developed residential properties between 20th Street and 24th Street. Upstream of 24th Street, the stream adjoins and bisects 20