FLOOD01280

• Designation Number: 93
• County: Jefferson
• Community: Lakewood
• Stream Name: McIntyre Gulch
• Title: Flood Hazard Area Delineation - McIntyre Gulch, Lakewood, CO
• Date: 10/1/1977
• Designation Date: 1/1/1978
• Floodplain - Doc Type: Floodplain Report/Masterplan

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CHAPTER II
GENERAL STUDY AREA DESCRIPTION,

a drainage area for McIntyre Gulch of 4.6 square miles. The Intermediate

Regional Flood (approximately the 100 year recurrence interval) discharge

at the confluence with Lakewood Gulch was estimated to be 3100 cfs by the

A. Study Area
The McIntyre Gulch Basin drains the eastern flank of Green Mountain
and the drainageway runs eastward through the central portion of Lakewood,
Colorado. The Gulch is a major tributary of Lakewood Gulch, the confluence
being immediately west of Wadsworth Blvd. and north of West 6th Avenue.
The basin location and boundary are shown on sheet no. 2 of the Appendix
to this report. The total basin area at the confluence is 4.8 square miles,
and the channel length measured from the upper or westerly extent of the
basin boundary to the confluence is 6.0 miles.
The basin description and numbe~ing as set forth in the Project Reuse
"Drainage Basin Descriptions, Sub-basin Delineation and Summaries" of March

U.S.A.C.E. study.

B. Hi story
The urbanization of McIntyre Gulch commenced in the 1940's with the
development of the area between Garrison Street and Union Blvd. occurring
in the late 1940's and early 1950's. The Federal Center also began developing
during the 1940's as part of the World War II defense effort and has evolved
into a large multi-agency office and laboratory o~ research facility complex.
The development west of the Federal Center started in the early 1960's
and has continued to date. The pattern of development, with the lower
portion of the basin being urbanized first, aggravated the storm runoff
situation, since full floodway easements were not incorporated into the

McIntyre Gulch
Project Reuse Basin Description

development. As urbanization progressed further upstream, significant
storm runoff has occurred more frequently and with some increase in peak

1972 is as follows:

flow for a given rainfall.

McIntyre Gulch
(west)

1-59-4803-02
A = 2.37
L = 2.54
LCA = 1. 33
S = 0.082
Land Use Index 1.60

McIntyre Gulch

1-59-4803-01
A = 2.80
L = 2.84
LCA = 2.31
S = 0.018
Land Use Index
2 . 72 - 3. 20

However, erosion and the potential for flood damage during major storms
existed along McIntyre Gulch after the initial development (early 1950's)
as evidenced by the two photographs showing McIntyre Gulch during the flood
of June 1963, and immediately after the flood of August 1965 (Figure 1). The
photographs were taken behind the house at 8525 West 3rd Place.
Prior to urbanization, some irrigated farming was practiced in the middle
portion of the basin (below the Agricultural and Welch ditches). The lands
adjacent to the reach from 6th Avenue to Carr Street are still utilized

The total basin area defined by Project Reuse was 5.17 square miles.
The basin boundary has been defined in more detail in the process of this
and an on-going study for South Lakewood Gulch (also sponsored by U.D & F.C.D.
and the City of Lakewood), and the total tributary area is 4.8 square miles.
The Flood Plain Information Study, Volume IV, Denver Metropolitan Region,
completed by the Corps of Engineers and published in October 1968 indicates

primarily for pasture. A significant area of the Jefferson County School

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