O-2000-2454 - Laserfiche WebLink

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PROJECT DESCRIPTION The Project consists of two (2) major components. The first is the replacement of eight- inch waterlines along Belfast and Piney Brook, including the replacement of sidewalks, and the replacement of the eight-inch waterline crossing Big Island Slough at Catlett. The second portion of the Project involves the rehabilitation of approximately 2,825 feet of eight-inch sanitary sewer between Rustic Rock Road and Rustic Gate Road from Maplewood Drive to Roseberry Drive. The waterline replacement portion of the Project is a continuation of the systematic replacement of old cast iron lines in the original Fairmont Park subdivision. These lines are subject to frequent leaks and breakage's, and have resulted in sidewalk displacement in this area. The sanitary sewer rehabilitation portion of the Project was developed from the systematic televised inspection of the City's sewer system. This segment of the system has experienced frequent service interruptions from misaligned joints, poor soil conditions, and storm water inflow. Because of the numerous services on this line segment (79), the depth (average 12 feet) and its location between houses, trenchless rehabilitation is advisable to avoid disruptions. Additionally, the use of sliplinning is not advisable due to the reduction in pipe diameter using this method. It has been determined that the current eight-inch size is desirable. Several technologies are available for trenchless rehabilitation with minimal loss of pipe diameter, including cure-in-place and pipe bursting. Cure-in-place has been used in La Porte many times, with good results. It is somewhat more expensive than other methods. Pipe bursting, although not yet used in La Porte, is a mature technology with a history of success in this area, with favorable costs. The proposed engineering services agreement will examine these methods and develop specifications that fit the conditions revealed by TV tapes supplied by the city and the geotechnical report. Due to the potential for service disruption and the need to excavate and reconnect sewer taps from the surface, a full-time project representative is recommended. Inspection of the waterline installation can also be accomplished by the same inspector as the two projects are in adjacent neighborhoods. The Project should be designed, bid and awarded by March 2001. With an estimated construction of 90 working days, the Project is estimated to be completed by July 2001.