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One-of-a-kind
Other Projects:
Lake Dorothy
Snettisham
Crater Lake
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Snettisham Hydroelectric Project
near Juneau, Alaska

Project Description

The Snettisham Hydroelectric Project, located 28 air miles southeast of Juneau, Alaska, includes over 8000 feet of essentially unlined power tunnel, a 900 foot deep surge shaft, an underground machine shop and an underwater lake tap into a high mountain lake under 210 feet of water. At the time, the project represented the highest head lake tap performed in North America. Also included were several large underground chambers, ranging in excavated volume from 37,500 to 180,000 cubic feet.

Scope of Services

Lachel & Associates, Inc. was selected as the Title II Construction Manager for both tunnel construction phases of the Crater Lake portion of the Snettisham Hydroelectric Project. Lachel was responsible for the design of ground support systems, rock mechanics instrumentation, water control, geologic field mapping, cost estimating in support of change orders and contractor claims, monitoring and analysis of blasting schemes and vibrations, and the review of the construction contractor's safety and construction procedures. The first contract, which included over 7000 feet of tunnel was completed ahead of schedule, within budget, with only one minor lost time accident and without a single contractor claim. For its efforts, Lachel received a Letter of Commendation from the Corps of Engineers, which said in part:

"It is well recognized that you and your staff provided sound technical advice based on years of experience, continually sought new data to incorporate into field construction decisions and maintained a superior rapport with the construction contractor, the Corps of Engineers and the using agency on this highly visible project. Your professionalism, enthusiasm, eagerness to excel and communication skills contributed to the successful completion of this contract. You are also to be commended for your contributions to the project safety by making needed recommendations which led to a safer work environment - - for all those working in hazardous underground conditions."