Central Alabama Water โAdvances Lake Purdy Damโข Rehabilitation wiht Additional investigations
Central Alabama Water (CAW) is โฃundertaking a $28 million, multi-phase project to rehabilitate the Lakeโ Purdy โDam, originally constructed in 1909 adn raised in 1929. The current โฃPhase 1 focusesโข on strengthening โฃthe dam’s structure with roller compactedโ concrete. Recently,the CAW board approved three additions to the ongoing work,aimed at a comprehensive assessment and reinforcement ofโ the historic dam.
These additions includeโ a dye test to identifyโ potential seepage pathways, exploration drilling onโฃ the dam’sโ left (downstream) side, and the installation of a deep foundation utilizing micro piles on the โขright side. schnabel Engineering will conductโ a reservoir โคdye test as early as next week,releasing โขtwoโข non-toxic,biodegradable,and NSF-approved dyes upstream. Engineers willโข monitor the downstream area for three hours to observe dye movement, potentially resulting in temporary discoloration of the Little Cahaba โฃand Cahabaโข Rivers. Officials emphasize thisโ poses no risk to the river ecosystem โขor drinking water,as water from โthe Cahaba River undergoes โฃfiltration and treatment at the Shades Mountain Filter Plant.
The exploration drilling on the left sideโฃ of the dam will confirm geological conditions and is expected to โtake one to two days at a cost of approximately $25,000. Together, โengineers will begin installing a deep foundationโ on the right side, involving drilling, inserting steel pipes filled with rebar and concrete, and capping with a concrete slab. design โคfor this foundation is anticipated to take two weeks,with construction slated โfor completionโ by the end of December.
CAW Vice-Chairman Phillip Wiedmeyer, aโค retired engineer, โขhighlighted the importance โof โthe project, stating it’s a “generational opportunity” to ensure the dam’s continued service to customers. he further explained the rationale behind the โadditional exploration, โnoting that conducting it before concrete is poured โallows for informed decision-making at minimal expense.
Despite the โฃongoingโ work, CAW assures the public โthat Lakeโข Purdyโ Dam remains safe. Asโ of October 17th, the โคreservoir was nineโค feet below full capacity due toโ typical late summer/early fall dryโข conditions. Officials โstated that overโข seven inches of rainfall within a โฃ24-hour period – equivalent to a 25-year storm – would โbe required for waterโฃ to reach the dam’s crest,indicating a low risk of overflow.
The boardโฃ has postponed a vote on engaging โanโ outside expert for a separate โreview of the dam’s โoverall โคhealth.
