PROJ00143

• Contract/PO #: C153810
• Contractor Name: Wood Lake Mutual Water & Irrigation Company
• Contract Type: Loan
• Water District: 1
• County: Weld
• Bill Number: SB 97-008
• Loan Projects - Doc Type: Feasibility Study

I
I
I
I

WOODS LAKE DAM
Engineering Evaluation

A,l

PROJECT INFORMATION

A.I.I General.

I
I
I
I
I
I
I
I
I
I

This report summarizes an investigation by SMITH GEOTECHNICAL! Engineering Consultants
conducted on the Woods Lake Dam for the Woods Lake Mutual Water & Irrigation Company, The
investigation consisted a subsurface investigation of the dam embankment, laboratory testing of soil
samples retrieved from the dam embankment, and a survey of the dam to determine potential freeboard
problems. This study was prompted by a request by the Colorado Division of Natural Resources, Dam
Safety Branch to investigate the dam, its spillway, and outlet works.

This report also summaries our conclusions and recommendations concerning the condition of the dam and
provides some alternative solutions for repair of the dam and outlet works, Cost estimates are provided
for the various alternatives proposed to repair the dam.

A.I.2 Site Location.

The dam is located in Weld County, Colorado approximately 5 miles west of Eaton, Colorado, More
specifically the site is located in Section 5, Township 6 North, Range 66 West of the 6th Prime Meridian.
The dam site can be accessed from Weld County Road 74 shown on the site plan in Appendix A,

A,I,3 Purpose of the Investigation.

The investigation of the Woods Lake Dam was initiated due to concerns raised by the State Engineer
concerning the adequacy of the spillway and the condition of the outlet conduit. Letters from the State
Engineer dated February I, 1996 and March 18, 1996 are enclosed in appendix D.

The State Engineer has not restricted the water level in the reservoir but most likely will if their concerns
are not addressed. The purpose of this report is to provide a basis for determining what action must be
taken and to help the Company determine their options,

No hydrologic studies were conducted for the reservoir at this time.

I
I
I
I
I

A.2 GEOTECHNICAL INVESTIGATIONS

The onsite investigations included a subsurface investigation of the dam embankment, the installation of
one piezometer near the outlet works for monitoring water levels within the dam, and limited surveying
to define the dam section and crest elevation. A plan of the dam which shows its pertinent features and
boring locations is included in Appendix A of this report.

2