FLOOD08560

• Designation Number: 228
• County: Denver
• Community: Denver
• Stream Name: Westerly Creek
• Basin: South Platte
• Title: Flood Hazard Area Delineation - Westerly Creek
• Date: 3/1/1983
• Designation Date: 1/1/1984
• Floodplain - Doc Type: Floodplain Report/Masterplan

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October. 1973: "Preliminary Analysis for Urban Drainage Master Planning of the
Highline Canal" (Leonard Rice Consulting Water Engineers, Inc.).
This report, as it pertains to Westerly Creek, demonstrated that there is
essentially no drainage capacity in the Highline Canal (primarily an irrigation
facility) for Westerly Creek flows because of inflow to the canal from other
basins.

January, 1977: "Flood Hazard Area Delineation, Westerly Creek" (Camp Dresser
& McKee, Inc.).
This report delineated the 100-year floodplain and floodway based on hydrologic
and hydraulic conditions existing at the time the report was prepared. This report
is the base from which the current study is derived and has been used extensively
for baseline information.

January, 1976: "Report on Drainage Master Plan for Westerly Creek" (Camp
Dresser & McKee, Inc.).
This report indicated that the basin is fully urbanized in the lower reaches and is
rapidly approaching a state of full development in the upper reaches. In the area
upstream of the Highline Canal, three storm water detention ponds and a concrete-
lined flood channel have been constructed by the City of Aurora and have
alleviated the flooding problems in this area. Below the Highline Canal, the
construction of Lowry Air Force Base has obliterated the historical
Westerly Creek Channel. The Kelly pond is inadequate to serve the total
upstream watershed. The Westerly Creek channel and flood plain between
Kelly Pond and Stapleton Airport have been greatly altered by development and
encroachment. Existing open channel sections and drainage structures have
insufficient capacity to receive even local tributary flows. The drainage structure
passing through Stapleton Airport has capacity for only an 8-year storm event. A
combination of detention pond storage and flood channel improvements below
Highline Canal was recommended by this report.

November, 1978 to Present: "Contract Drawings for Construction of
Westerly Creek Storm Drainage Phase I, Schedules I to V". (Merriclr & Company).
These documents comprise the construction drawings for the improvements
proposed in the other reports. These drawings were the basis for the channel and
crossing sections modeled as part of the hydraulic analysis for this study.

In addition to the summarized reports previously described by Camp Dresser and
McKee, Inc., above, the following reports provided additional useful information:

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