Agenda - Public Works Committee - 04/18/2017

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Public Works Committee 5. 1. Meeting Date: 04/18/2017 By: Mark Riverblood, Engineering/Public Works Title: Consider Preventative Maintenance for 29 year -old Well Pump and Motor at Central Park Purpose/Background: The purpose of this case is to recommend to City Council the authorization to perform preventive maintenance for the water supply well associated with the Park Center Building at Central Park. The 4" residential sized well was put into service in 1988, and has performed without any problems since. In approximately 2006, the concession stand or Lion's Pavilion was completed, and a 2" inch underground water supply line was routed from the Park Center building to also serve the new concession stand. Altogether, between the two buildings, there are 23 separate fixtures, including various faucets, sinks, toilets, urinals, drinking fountains and the misting station between the buildings. These park buildings are used every day from early spring through late fall, with the Park Center Building in service year -around. While the well has not failed, this size of well and annual use (amount of water pumped) would be comparable to a residential property with irrigation. Accordingly, the average service life for the 4" submersible well pump and motor would be around 15 years. Timeframe: The background and overview of this case presentation may be less than 5 (five) minutes. Observations/Alternatives: Observations: Water supply wells typically only fail when they are in use. If, (or when) the well that is the subject of this case fails, it is likely to cause significant inconvenience to park users —especially if it were to occur during a weekend tournament, where restrooms would be out of service, and the concession stand would need to be shut down. Another example of significant disruption would be during an election day (the Park Center Building is a Polling place). On March loth, 2017 the motor and pump were pulled from the well casing and tested. After 29 years of continuous use, the thrust bearing that couples the motor and pump was found to be worn, confirming that preventative maintenance —replacing the pump and motor —should be scheduled. The following are alternatives to consider: 1. Do nothing at this time, and react to a potential water supply failure in the future. 2. Schedule pump and motor replacement in a future year. 3. Replace Pump a. Replace the pump and motor early in 2017 with a 1 1/2 hp motor and pump (same as in use today). This option is about $5,000. b. Replace the [existing system] with a 3 hp Variable Frequency Drive and pump (Staffs recommendation) due to the longer service life and other benefits. This option is < $9,000. Additional information will be available at the meeting. Funding Source: