FLOOD03822

• County: Jefferson
• Community: Lakewood, Golden
• Basin: South Platte
• Title: Flood Hazard Area Delineation
• Date: 4/1/1978
• Prepared For: Lakewood and Jefferson County
• Prepared By: UDFCD
• Contract/PO #: &&
• Floodplain - Doc Type: Floodplain Report/Masterplan

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2. Station 84+00 to 60+40, DeFrame Way to Alkire Street (Sheet 17)
The channel in the lower portions of this reach consist of a
storm sewer and inlets ranging in size from a 24" to a 36" RCP. The sewer
begins at Braun Street (71+00), flows easterly between the houses and discharges
into the improved channel east of Alkire Street. The sewer system has a
capacity between the 2 year and 5 year frequency flood. Above Braun Street,
the channel consists of street flow down Exposition Drive. The overall
slope of the drainageway is about 6%.
Above Braun Street, the flood plain is generally contained within the
street R.O.W. with some local property flooding at the street intersections.
Below Braun Street, the storm runoff in excess of the storm sewer capacity
will flood the area between the houses in the form of sheet flow, due to
the lack of channel capacity and considerable obstruction from fences and
shrubs.

The flood plain is generally contained within the channel area with
some street overtopping occurring at Wright Street and Youngfield Street.
The flood hazards in the reach consist of erosion, debris removal
and cleanup, interrupted traffic and services, and a low life hazard
due to the moderate depth and flow velocity.
4. Station 24+20 to 0+00, Alameda Drive to Confluence (Sheet 19)
The channel in this reach consists of a 78" RCP culvert under the
Green Mountain Shopping Center and an improved V-shaped and trapezoidal
shaped section. The channel which is crossed by Union Blvd. has an
average slope of 3.4%. The flood peaks are generally contained within
the channel with moderate flow velocity.

The flood hazards consist of erosion, debris removal and cleaning,

interrupted traffic and services, and a low life hazard due to the moderate

depth and flow velocity.

The flood hazards in the reach consist of erosion, debris removal
and cleaning, deterioration of the street, interrupted traffic and services,
content damage to the houses, and a low life hazard due to shallow flooding
in Exposition Drive.

D. Drainageway D
Drainageway D is the designated main channel of McIntyre Gulch draining
the northeast flank of Green Mountain.

1. Station 117+00 to 106+00, Upstream Study Limits to Alaska Drive
(Sheet 20)

3. Station 60+40 to 24+20 Alkire Street to Alameda Drive Sheets
17, 18 & 19

The channel in this reach consists of a combination of a 36" RCP
storm sewer, street flow (So Fig Way), paved channel and overland flow
through the low density residential area. A secondary storm sewer system
(18", 24" and 27" RCP) has been constructed about 400 feet south of
S. Fig Way and serves a smaller portion of the drainage basin (A-J7 Ac.).
The primary sewer system has a capacity equal to the 10 year frequency
flood peak. The secondary sewer system has the capacity between the 10

The drainageway in this reach consists of a parabolic shaped
natural channel below Wright Street and a trapezoidal shaped improved channel
with check drops above Wright Street. The average slope of the channel
(without check drops) is about 4.5%. The channel is crossed by Wright Street
and Youngfield Street.

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