Item 4E AudioItem 4EA Contract for Sanitary Sewer Manhole Repair
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Staff recommends that the City Council Approve contract for manhole rehabilitation
with Lewis Concrete Restoration in the amount of $ 70,000
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In late 2010, RJN Group engineering completed a comprehensive assessment of
the Southlake waste water collection system. Generally they found the network of
pipes to be in good condition and adequately sized to serve the needs of our
customers. Most of the defects found were on the concrete structures in the system
such as manholes, Junction boxes and lift stations.
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As waste water ages in the collection system, biological activity begins
decomposing the nutrients in the sewage. The fact that so much of Southlake’s
waste water is collected in lift station wet wells and pumped to higher elevations ads
to this detention time. The formation of hydrogen sulfide in the system presents a
respiratory hazard and in the presence of water, it forms sulfuric acid. Constant
exposure to this acid will literally dissolve concrete structures over a number of
years. The purpose of this project is to coat the interior of the structures with an
epoxy coating to prevent further damage.
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In July 2011 we solicited sealed bids for concrete restoration services. The project
was started using Wastewater Division funding from FY 2011. Because it is clear
that this project will exceed $50,000 during FY 2012, staff is requesting council
approval to continue the project with up to $70,000 funds remaining in the 2012 CIP
for sanitary sewer repairs.
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The award of the manhole rehabilitation project links to the city’s strategy map
relative to the focus area of Infrastructure. The specific corporate objective is invest
to provide and maintain high quality public assets.
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If you have anyquestions regarding this item, contact Bob Price at 748-8097
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