FLOOD07758

• County: Denver
• County: Jefferson
• Community: Lakewood, Denver, Jefferson County
• Stream Name: Lakewood Gulch
• Basin: South Platte
• Title: Major Drainageway Planning
• Date: 12/1/1979
• Prepared For: Denver / Lakewood / Jefferson County
• Prepared By: UDFCD
• Contract/PO #: &&
• Floodplain - Doc Type: Floodplain Report/Masterplan

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II GENERAL BASIN DESCRIPTION

5

The Lakewood Gulch channel is well defined in all locations, but

it is constricted at most street crossings. A number of the

constrictions are severe enough to cause extensive ponding

upstream and overtopping of the streets in excess of the allow-

able depths recommended by the Urban Storm Drainage Criteria

Manual (Reference 1). In some cases, the overtopping flow

splits from the main course, causing additional flooding of

land somewhat distant from the main channel. A detailed dis-

cussion of the flooding and the proposed improvements is given

opposite each master plan drawing.

Lakewood Gulch is a well defined drainageway, collecting and

conveying runoff from the foothills in Jefferson County and

from a highly urbanized watershed in the City of Lakewood and

the City and County of Denver. A small portion of the studied

length of Lakewood Gulch is located in unincorporated Jefferson

County. Its general location is illustrated on Sheets 1 and 2

of the Masterplan in Chapter VII. The predominant length of

the Gulch lies in the City of Lakewood; the remainder is in the

City and County of Denver. The overall drainage basin contains

approximately 16.0 square miles. Lakewood Gulch and its major

tributaries flow in an easterly direction from the foothills

to the confluence with the South Platte River, a basin length of

approximately 10 miles. The greatest width of the basin is

about 2.5 miles. The portion of Lakewood Gulch which is the

subject of this report is located between Nest 6th Avenue and

the South Platte River. The studied channel has a length of

approximately 8.41 miles, of which 0.62 miles are in Jefferson

County, 5.45 miles are in Lakewood, and 2.34 miles are in Denver.

The soils of the watershed are comprised primarily of the Piney

Creek Alluvium in the channel bed and of Lower Verdos Terrace

or pediment deposits in the remainder of the basin. Consider-

able amounts of artificial fill can be found along the channel

in the urbanized portions of Lakewood and Denver. The piney

Creek Alluvium is generally described as having a low permea-

bility. The water table is generally 5 to 10 feet below the

surface, but may be deeper during fall and winter. Compacting

usually is easy with sheepsfoot or rubber-tired rollers.

Excavation is east with power equipment. Foundation stability

conditions are fair to poor, and clayey parts of this unit may

swell moderately when wetted. Cut slopes may stand vertically

for extended periods if dry, but eventually will slump to stable

slopes between about 3:1 and 6:1. The deposits are subject to

moderate erosion, particularly along stream banks, and to gully

erosion on terrace surfaces.

The three major tributaries of Lakewood Gulch -- Dry Gulch,

McIntyre Gulch and South Lakewood Gulch -- are not analyzed

within this report, but studies for each have been prepared by

the UDFCD under separate contracts.