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Item No: 8H Meeting Date: December 8, 2014 Type of Business: Consent Agenda Administrator Review: ____ City of Mounds View Staff Report To: Honorable Mayor and City Council From: Nick DeBar, Director of Public Works Item Title/Subject: Resolution 8345, Authorizing Stantec Consulting Services Inc. to Perform Professional Engineering Design Services and Prepare Bidding Documents for Groveland Lift Station Rehabilitation Background: The Groveland Lift Station is one of two sanitary lift stations owned and operated by the City. The Groveland Lift Station is a duplex wet well / dry well station originally constructed in the mid-1960s. The station is located in the boulevard on the northeast corner of Ardan Avenue and Groveland Road in next year’s Area H street project. The station consists of an underground wet well and dry well. The control panel is mounted inside the below grade dry well and the telemetry panel is located on a rack located between the two structures. The current pumps, 7.5-HP Chicago Pump Co., VPMOM-4 Flushkleen Sewage Ejector pumps are located in the dry well, and are the original pumps installed back in 1965. The original piping system incorporated a proprietary “flush-Kleen” system that allowed the pumps to be back- flushed. This portion of the piping has been abandoned and is no longer operational. The original pump design capacity was 450 GPM at 32’ total dynamic head. The pumps cycle time is good and the acceptable run times show that the existing wet well is currently at an acceptable size for the flows entering the station and that the pumps are more than adequate for the incoming flow. The Groveland Lift Station is generally in good condition structurally. There is no evidence of water infiltration into the station which is very good for a station of this age. However, the piping, valves and pumps as well as all of the electrical controls and miscellaneous devices are in somewhat poor condition due to their age. However, there are flooding concerns associated with the pumps and panels located in the underground dry well. Also, the need to enter a confined space to access the pumps and controls for maintenance is not desirable. The existing access chimneys are very small and make a confined space rescue extremely difficult. Discussion: Public Works has discussed with the Council the need to rehabilitate the station and the opportunity to have this done with the Area H project. Rehabilitation work will consists of converting to a duplex submersible lift station to alleviate the flooding concerns associated with the dry well and to eliminate the need to access a confined space to gain access to pumps and controls. The walls of the wet well and dry well would be extended up to the surface through the use of larger precast concrete manhole sections to reduce costs. The addition of new aluminum access hatches will be required in the new precast top slabs as well. Pumps would be accessed through the wet well extension and the dry well extension would become the valve vault. The existing dry well would be filled in. In addition to these improvements, it is also recommended that a new stand-by generator be installed next to the station like the other two options. This option would remove the structures from possibly entering into the street section and would put the two manholes in the sidewalk area. Public Works solicited a fee proposal from Stantec to perform design, bidding, and construction services on the station. Attached is the design fee proposal from Stantec for $44,000. The proposal is intended to add the lift station rehabilitation construction work, estimated to be approximately $250,000, to the bidding documents for the Area H street project. Many efficiencies