Council supports change order to add air relief valves to Maria pump station; engineers estimate ~$200,000

City engineers and public works staff told the council that the Maria pump station’s new pumps will introduce air into a mile of force main and that air can ‘‘hammer’’ pipe joints, shortening the pipeline’s useful life and risking damage to the pumps. The engineers recommended installing air relief valves near Annapolis and at a second location; staff estimated the work at about $200,000.

Public works staff recommended issuing a change order to the contractor already mobilized on the lift station project so the work can be completed before the pumps are placed in service. Council members raised two considerations: (1) issuing a change order to the mobilized contractor keeps warranty and commissioning with the same contractor, reducing risk; and (2) going out to a new bid might reduce price but would increase mobilization costs and delay the work. Several council members argued in favor of option A for speed and warranty reasons. Staff said the change order would be charged to the sewer capital contingency and that the formal change order would be returned to council for approval at a future business meeting.

No formal vote was recorded in the work study; staff were directed to proceed with change‑order negotiations and to return with the formal change order for council approval.