Title
131st Street Lift Station Repairs - Board Approval
History
In late July, two of three pumps at the 131st Street Sanitary Sewer Lift Station failed. Both pumps were sent to Gasvoda & Associates, Inc. (GAI) of Calumet City, Illinois (the manufacturer’s authorized service representative) for evaluation. Both motors were found to be bad. Recent history at this lift station is a series of chronic motor failures. Staff worked in earnest with GAI in an effort to identify a reason for the recent motor failures with no clear cause identified. Following this effort, staff contacted Greeley and Hansen LLC (G&H) of Chicago, Illinois, to review the operation of the station in consultation with GAI and the Utility Division staff. During this review period, interim repairs were made to the motors by GAI at a total cost of $7,653.54. While the interim repair work was underway, Godwin Pump of Lansing, Illinois, was contracted to provide emergency pumping capability to prevent sanitary sewer backups (capacity was reduced by 2/3). The total cost for this service was $13,484.60.
After considerable review of the current operating characteristics of the station and discussion with GAI and the Utility Division staff, G&H has made several recommendations:
1. Replace existing motors as a result of excessive heat damage due to current operating conditions. (Existing motors have been rebuilt multiple times but can be maintained as spares.)
2. Replace existing Variable Frequency Drives (VFDs) due to reaching their expected lifespan. (The existing VFDs are fifteen (15) years old with a normal lifespan of ten (10) years.)
3. Replace existing controller to provide additional control flexibility and avoid operating conditions outside the manufacturer’s recommendations.
Item 1: Motor Replacement
GAI has provided a quote to replace three (3) motors. The cost of each motor is $7,363 for a total of $22,089. To ensure factory warranty, GAI will complete the installation ...
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