2023.04.17 Packet - Laserfiche WebLink

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Mr. Bryan Bear April 13, 2023 Page 2 As outlined in our sewer rate justification report, trunk Sanitary Lift Stations are to be paid for and constructed by the City of Hugo. Preliminary project cost estimates are estimated to be in the $600,000-$650,000 range. The members of our team have completed numerous sanitary sewer lift station projects in the metro area including the Rice Lake Reserve Lift Station. PROJECT UNDERSTANDING Proposed Lift Station: The proposed lift station will consist of a concrete wetwell with duplex pumps, a concrete valve vault with check valves, air release valves, all interconnecting piping, hatches, and appurtenances. Our design fees assume that a precast concrete wet-well and valve vault will be designed and constructed. Electrical/SCADA System: Available electrical service to or near the site is believed to be three phase. If three phase power is available, the pumps can be operated with full voltage motor starters. If only single-phase power is available, the pumps can be operated with variable frequency drives (VFDs). The final choice of voltage and phase will also depend on the City’s preferences, so that the lift station is consistent with other locations and compatible with the City’s existing portable generator. The base design will include a freestanding control panel with interlocked main and standby circuit breakers and a receptacle for connection to a portable generator in the event of a power outage. In addition, the panel will include branch circuit breakers and motor starters or VFDs for operation of the pumps, a programmable logic controller (PLC) and operator interface terminal (OIT), and other components as required. The PLC will call for operation of the pumps based on start and stop setpoints entered at the OIT and compared to level in the wetwell as measured by a submersible level transducer. High- and low-level float switches in the wetwell will be connected to hard wired circuitry in the control panel to provide backup pump control, in the event of a PLC or level transducer failure. The control panel will be monitored remotely via a communication system that is compatible with the City’s existing monitoring system. The base bid design for the control panel will include spare space inside to allow for installation of a future automatic transfer switch, and spare conduits will be stubbed out from the panel to allow for connection to a future permanently installed on-site generator. The base bid design will include a spare conduit stubbed out from the panel to allow for connection to a future fiber optic cable for remote monitoring. An evaluation of the control design, components, and other City preferences will be conducted during both preliminary and final design. Forcemain: The size and route for the proposed forcemain will be determined during the design process, but it is expected to be located within Oneka Parkway and connecting directly to the last sanitary manhole located within Oneka Parkway constructed as part of the Oneka Place development. The timing of placement will be coordinated with the Oneka Prairie development and potentially constructed with the development. The forcemain will be installed with open trench method. Geotechnical Analysis: Soil borings and a geotechnical analysis are required to determine the characteristics of the existing soils and the groundwater conditions and provide recommendations on buoyancy accommodations to ensure the structure does not move.