FLOOD04928

• County: Denver
• County: Jefferson
• Community: Denver, Edgewater, Lakewood, Wheatridge
• Stream Name: Sloans Lake Basin
• Basin: South Platte
• Title: Major Drainageway Planning
• Date: 12/1/1977
• Prepared For: Denver / Lakewood
• Prepared By: UDFCD
• Contract/PO #: &&
• Floodplain - Doc Type: Floodplain Report/Masterplan

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silt and clay with humic bog clays interbedded in places and also

commonly found in the upper 1 to 2 feet. Saturated sand and gravel

can yield as much as 2000 gpm of water which has a generally good

chemical quality. Engineering properties of this geologic formation

include:

1. Generally low permeability;

2. Water table generally 5 to 10 feet below ground surface;
however, seasonally quite variable;

3. Compaction is generally easy with sheepsfoot roller;

4. Foundation stability conditions for heavy structures are
fair to poor;

5. Cut slopes may stand vertically for short periods of time
but will eventually slump to stable slopes that can range
between 2-1/2:1 to 6:1;

6. Moderate to moderately resistant to erosion.

layer of silt loam to silty clay loam about 8 inches thick. The sub-

soil to a depth of about 32 inches is a silty clay loam. Weld soils

have a silt loam surface layer of about 5 inches thick. Their subsoil,

about 21 inches thick, can be a mixture of clay loam, silty clay, and

silty clay loam. Engineering properties of this soil association

i nc 1 ud e :

1. Depth to bedrock greater than 60 inches;

2. So; 1 classification: (a) Unified System: Cl or CH

(b) AASHO: A-7;

3. Permeability is generally slow (less than 0.63"/hour);

4. Water holding capacity is about 0.25 inches/inch of soil;

5. Salinity is none to moderate;

6. Shrink-swell potential is variable from low to high.

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The loess deposits located both in the eastern and western portion of

the basin range from 0 to 40 feet thick; however, most commonly found

to be around 10 feet thick. The material is generally a sandy silt in

which the upper 2 or 3 feet may contain appreciable amounts of clay.

Saturated sandy deposits may yield water at a rate of 1 to 5 gpm.

Engineering properties of this geologic formation include:

1. Moderate vertical and low lateral permeability;

2. Water table is generally absent;

3. Compaction is generally easy with sheepsfoot roller;

4. Variable foundation stability;

5. Cut slopes will stand vertically for several years but will

eventually slump to stable slopes of about 2:1 to 4:1;

6. Moderately resistant to erosion.

Records of test holes drilled on the north side of Sloans lake by the

Denver Parks Department revealed the following:

1. SIeve analysis results:

Passing

Per Cent Range

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2.
3.
4.
5.

No.4 100
#10 99.6
#40 96.2
#60 90.2
#200 64.0

liquid limit: 32.8 to 38.6

Plastic limit: 15.6 to 16.1

AASHO Classification: A-6(10)

Depth to Water Table: 7 - 11 feet

100
98.8
96.4
74.4

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DEVELOPMENT STATUS

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For the most part, the soil class of the basin ;s composed of the

Fondis-Weld Association, which is generally characterized as being

deep, well drained, nearly level and gently sloping, loamy soils that

have clayey layers in the subsoil, and formed mainly in wilty, wind-

deposited material on upland plains. Fondis soils have a surface

With the exception of 74 acres of vacant land adjacent to the American

Medical Center for Cancer Research in lakewood, formerly the Jewish

Consumptive Relief Society (JCRS), and a few isolated vacant lots

interspersed throughout the area, the entire basin is fully developed,

consisting of primarily single family residential dwelling units.

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