Public Works recently switched potable water pumping practices.  Previously, the Supervisory Control and Data Acquisition (SCADA) software based its operations on water levels in the Village's elevated water tanks. The new system is based on water pressure.  This conversion was possible due to the installations of Variable Flex Drives (VFDs) which allow potable pumps to ramp up and down slowly, therefore reducing pressure spikes.  Pressure spikes have been determined to be a significant factor in the number of water main breaks the Village experiences yearly.

The next step in our plan to reduce the potential for water main breaks is to properly size pumping components to utilize a greater flow from each pump.  Currently, some of the system pumps can only vary flow between 85%-100% of maximum pumpage. A modern pumping system can modify pumping output in a greater range varying from 65%-100% of maximum pump capacity.

The engineering firm AECOM designed and assisted with the first programming phase of the program.  Since the firm is most familiar with the existing pump and motor capabilities, staff believes they are most qualified to make recommendations, based upon relevant data that will enable the Village to operate the pumps with a greater range of flows.

The cost of the engineering analysis and plan would not exceed $34,800. This proposal would provide a plan for the replacement or modification of all pumps and a comprehensive plan for modernization of all motors at pump stations to ensure many years of reliable service from the new VFD's. The report would be complete with cost estimates and part numbers to facilitate ease of planning and implementation.  Funds are available for 2020 in account 505-7201-561-2005.

RECOMMENDATION

It is recommended that the Village Board award a contract for a comprehensive potable pump and motor study and comprehensive replacement plan to AECOM for a not-to-exceed amount of $34,800 and authorize staff to execute the necessary documents.