FLOOD02223

• County: Arapahoe
• Community: Littleton
• Stream Name: Upper Slaughterhouse Gulch
• Basin: South Platte
• Title: Major Drainageway Planning
• Date: 3/1/1983
• Prepared For: Littleton, Arapahoe County
• Prepared By: UDFCD
• Contract/PO #: &&
• Floodplain - Doc Type: Floodplain Report/Masterplan

CHAPTER II - GENERAL STUDY AREA DESCRIPTION

3, Fondis Silt Loam - (Most prominent soil type found throughout entire
basin) ,

A, Study Area

4, Litle Silty Clay Loam - (Small area above Arapahoe Road),

Slaughterhouse Gulch lies within southcentral portion of the Denver Metro-

politan area. The upper end of the basin is located approximately 3/4 of a mile

south of Arapahoe Road in the vicinity of the Southglenn Shopping Mall, The con-

fluence with the South Platte River is located approximately 1/4 mile south of

Belleview Avenue, The basin location and boundary are shown on Figures 11-1 and

11-2. The basin index number as set forth in Project Reuse "~~ge Basin Descrip-

tion, Subbasin Delineation and Summaries" is 1-05-5700-01.

5. Nunn Loam - (Found in lower reach outside the channelway area),

6. Renohill - Buick Loam - (Small area near Broadway and Orchard Avenue),

These soils were derived from wind and water laid sediments of the Denver and Dawson
formations. The soils all fall within the Hydrological Soil groups C and D with the
exception of the Ascalon Sandy Loam, which is in group B, Other soil types may be
found within the basin, These were imported during the construction of the sub-
divisions.

The study reach for the Upper Slaughterhouse Gulch drainageway, under this

contract, extends from Powers Park up to Arapahoe Road, The area of the basin

tributary to Powers Park is 1.50 square miles (953 acres), The entire study area

lies within the City of Littleton and Arapahoe County.

C. Impervious Land Density

B. Topographic and Geological Features

The impervious land density was defined using the existing development and

zoning maps for the City of Littleton and Arapahoe County, There are only two areas

in the basin study area that are not fully developed. One area is West Grant Street

between Caley Avenue and Orchard Avenue and is approximately 40 acres, The other

area is north of Powers Avenue between Bannock Street and Delaware Street, and is

approximately 10 acres, The existing basin is 41% impervious and will increase

to 44% impervious when fully developed.

The Upper Slaughterhouse Gulch basin drains generally in a northwesterly

direction. The high point, located 3/4 miles south of Arapahoe Road and the South-

glenn Shopping Mall has an elevation of 5620-feet. The elevation of the lower end

at Powers Park is 5400-feet. The total length of the basin is approximately 3,]

miles with slope of 71-feet per mile (1,3%). The Denver Highline Canal flows

easterly through the basin as shown on Figure 11-2.

Listed on Table 11-1 is a land use summary for each sub-basin including, land

use, percent imperviousness, area, and jurisdication (i,e" City of Littleton or

Arapahoe County).

Soil Conservation Service (SCS) soil maps for the study area show six types

of natural soils which are all classified as loam soils. These soils are as follows:

I. Ascalon Sandy Loam - (Found in the lower reach adjacent to the channelway).

D, Drainageway Reaches

2. Buick Loam - (Found in the reach below the Denver Highline Canal and
adjacent to the channelway),

The 2.3 miles of drainageway within the basin study area were divided into five

channel reaches as shown on Figure 11-2, The reaches were selected to facilitate

development and evaluation of the alternative solutions to the drainage problems,

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