FLOOD09801

• County: Arapahoe
• Community: Greenwood Village
• Stream Name: Goldsmith Gulch
• Basin: South Platte
• Title: Contract Documents and Specifications for Goldsmith Gulch and Tributary Channel Improvements
• Date: 6/1/1987
• Prepared For: Goldsmith Metro District
• Prepared By: Greenhorne & O'Mara, Inc.
• Floodplain - Doc Type: Project

foundation system is opted for then the design and
construction criteria presented below should be followed.

(1) Piers should be designed for an allowable end bearing
pressure of 25,000 psf and a skin friction of 2500 psf
for the portion of the pier in bedrock.

( 2 )

Piers should penetrate at least three
into the bedrock, A minimum penetration
the bedrock and a minimum pier length
recommended.

pier diameters
of 5 feet into
of 14 feet are

(3) Piers should be reinforcej tteir full length with one
#5 reinforcing rod for each 18 inches of pier to resist
tension created by the swelling materials.

( 4 )

A minimum
facilitate
hole.

pier diameter of 10 inches is recommended to
proper cleaning and observation of the pier

(5) Pier holes should be proper:y cleaned prior to the
placement of concrete.

(6) The presence of water and granular soils in the
exploratory holes indicates that use of casing and
dewatering equipment i~ the pier holes may be required
to reduce water infiltration and accumulation. If
water cannot be removed prior to placement of concrete,
the tremie method should be used after the hole has
been well cleaned. In no case should concrete be
placed in more than 6 inches of water.

(7) A representative of the soil engineer should observe
pier drilling operations.

Trickle Channel: We understand that the proposed trickle
channel will be constructed of a concrete pan. Excavation
of the subgrade materials will be complicated due to the
presence of groundwater. We encountered groundwater in the
test holes at or near the 'proposed trickle channel grade.
These areas will have to be dewatered prior to the placement
of concrete. In addition, a measure to reduce the
hydrostatic uplift should be provided. The use of weep
holes or open joints is recommended. We recommend that
construction of the trickle channel and drop structures be
conducted during low runoff seasons.

The onsite soils exclusive of the topsoil are suitable for
supporting the trickle channels. It should be noted that
the natural sands and clays may swell if they are subjected
to a number of wetting and drying cycles. The concrete
trickle channel will be SUbject to movement and should be
designed with joints to handle this ~ovement.

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