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Kings Gulch the south, and parallels 4th Street along a steep grade to Boulder Creek. The drainage basin within the city limits is fully developed. A small tributary about 0.5 miles long enters the main Sunshine Canyon Creek drainage basin at Memorial Hospital. This tributary drains the area directly north of the hospital. The entire basin of this tributary is undeveloped. will overflow the ditch and sheet flow west through properties with the water eventually draining into Skunk Creek. The Kings Gulch drainage basin starts in the Boulder Flatirons and drains eastward from the mountains to lower-lying residential areas which start around 15th Street. From 15th Street to the stream's confluence at 22nd Street near King Avenue, the grade of the land is moderately steep. The basin is fully developed as a residential area. As such, the natural drainage channel is obl iterated. The channel within the undeveloped section of the basin is rocky, steep and narrow. The channel within the developed section is well defined, steep and na rrow. Goose Creek Gregory Canyon Creek The Goose Creek drainageway originates one block north of 9th Street and Alpine throu9h overland flow drainage of an area of approximately 200 acres. This area naturally drains to the east side of North Boulder Park. From here floodwaters enter Ba1sam Street from 9th Street. There is no stream visible within this portion of the drainage basin. The stream appears at 19th Street and Tyler Road, which is one block north of Alpine Avenue. The Gregory Canyon Creek drainage basin is steep, narrow, and appro~imately 1.9 miles long in its upstream and undeveloped section. The drainage starts near Green Mountain and continues northeastward towards the Boulder City limits. The drainage traverses fully developed residential areas between Baseline and Arapahoe Road along 9th Street for a distance of about 1 mile. The creek eventually empties into Boulder Creek north of 9th Street and Arapahoe Avenue. The channel within the upstream portion of the basin mirrors basin conditions. It is steep, rocky, and narrow. The downstream section of the channel through the developed areas is open and relatively steep in grade. Within the developed areas there are numerous road crossings. The channel within this section is narrow with steep banks at several locations. Deciduous vegetation borders and overhangs the channels. The drainage basin between North Boulder Park and the Boulder and Whiterocks Ditch has a moderate slope and is situated in developed residential areas. The stream bed within this area is very well-defined with heavy growth adjacent to the channel. The width of the channel within this section is as large as 25 feet with 6- to IS-foot high channel walls. The stream runs south of and parallel to Edgewood Drive. Homes border the stream along its length within this section. Sunshine Canyon Creek Under non-flood conditions, Goose Creek flows into the Boulder and Whiterocks Ditch. During a flood event, floodwaters traverse the ditch. The basin area east of the Boulder and Whiterocks Ditch is largely developed by a variety of commercial business. The channel through this area has been largely obliterated with development. Culverts under Foothills Parkway flows directly into two improved channels downstream for approximately 0.8 miles before joining again at a sediment pond just above the confluence with Boulder Creek. The Sunshine Canyon Creek drainage basin has its source in the mountains west of Boulder. The drainage runs from the mountains to Boulder Creek south of Canyon Boulevard at 3rd Street, an approximate distance of 2.2 miles. The majority of the basin exists in the mountains under undeveloped conditions. This portion of the basin is very steep, rocky, narrow and approximately 1.6 miles long. The basin enters the city limits near Memorial Hospital. It then turns to 3