Anticipate dewatering problems in advance

Message: Wells are only effective if they are strategically placed and coordinated with each other

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Lake Frances Dam was built in 1909, is 64 feet high, and stores 105,000 acre feet. Lake frances was ungoing a major rehab of the outlet works – involved replacement of the upstream section and sliplining the downstream section with steel pipe. A canal company was responsible for earthwork and dewatering and a contractor was hired for the sliplining operations.

Lessons learned:

• Dewatering can make or break a project, especially with fall construction – anticipate problems in advance
• You can tell right away if your dewatering system isn't working – don’t delay in trying something else.
• Calling in the experts can save you money in the long run.
• Wells are only effective if they are strategically placed and coordinated with each other

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  Lake Frances Dam New Intake Tower

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  The reservoir was drained down to dead pool, but ponding water was still a big problem. A couple of wells were drilled to dewater the site. These proved to be ineffective.

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  After over a month delay, with winter rapidly approaching, serious action was necessary. Godwin Wellpoint pumps were called in. They arrived with high powered pumps and set up a wellpoint system.

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  Well point system.

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  Godwin Wellpoint Pump

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  With the site properly dewatered construction was able to proceed on schedule

Note: The content on this page was originally created as part of DamOutletWorks.org (DOWL, 2018). It has subsequently been updated and reformatted as part of the Dam Safety Toolbox.
Revision ID: 3223
Revision Date: 09/15/2022