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Item No: 7N Meeting Date: May 14, 2012 Type of Business: Council Business Administrator Review: ____ City of Mounds View Staff Report To: Honorable Mayor and City Council From: Nick DeBar, Public Works Director Item Title/Subject: Resolution 7934, Approving Bidding Documents and Authorizing Advertisement for Bids for 2012 Sanitary Sewer Slip Lining Project Background/Discussion: The municipal sanitary sewer system is composed of approximately 44 miles of trunk sewer, 900 manholes, and 2 lift stations. The sanitary trunk sewer was largely constructed in the 1960’s and early 1970’s using (predominately) clay pipe. The use of clay pipe during this time was the industry standard, but more watertight pipe products (PVC) have been developed and replaced clay pipe to become the new industry standard the last few decades. Unfortunately, the leaky clay pipe incurs unnecessary Met Council treatment costs due to infiltration of ground water into the trunk sewer. In general, one gallon per minute of ground water entering the system equates to $1,000 of Met Council treatment costs annually. Public Works has an inspection and maintenance program for the municipal sanitary sewer system. This program includes inspecting the trunk sewer by televising camera and evaluating the condition of the pipe. There are a number of defects that are logged while performing inspections, including cracks in the pipe and leaking joints. Repair and remediation of these deficiencies are incorporated into the street and utility improvement projects as much as possible. However, there are trunk sewers not located in these project areas, and conditions of trunk sewers in project areas can change over time. A priority list that ranks the segments of pipe needing repair or remediation is maintained by Public Works. One technique used to fix pipes that are in good condition but have leaky joints is called slip lining. Slip lining is method that essentially places a hard liner inside the existing pipe – without digging up the pipe and streets. Slip lining is considerably less cost than trenching and replacing pipe, and there is no “inconvenience” cost compared to trenching methods. The Engineering Division of Public Works has prepared plans and specifications (bid documents) for use in obtaining public bids for a slip lining project. A public bid is required since the costs of construction will exceed $100,000. The 2012 budget includes $125,000 under the sanitary sewer enterprise fund for this work, which is likely less than what the bid documents include. However, the bid form itemizes the slip lining priorities in a base bid / add alternate structure that will be used to determine the successful bidder and quantity of work to be included in the project to meet the budget amount. Future slip lining projects will be pursued in coming years until the priority slip lining pipe segments are remediated. Recommendation: Public Works recommends that the City Council adopt the attached resolution. If adopted, the project will be advertised and bid in accordance with state statutes and a bid opening will be scheduled for June 4, 2012. The Council will need to award the project (tentatively scheduled for June 11, 2012) before any construction can begin. Respectfully submitted, Nick DeBar - Public Works Director