REVERE – A city plan to clean and upgrade flood prevention pumps includes a new alarm warning system for the Sherman Street pump.The pump failed during heavy rainfall on Aug. 8. Without a pump alarm, city workers were not alerted to rising water and sewage overflow problems on Sherman.The Sherman pump station and others located across the city are the main defense along with tide gates against flooding in low-lying neighborhoods.The city hired a consultant last spring to assess the pumps’ conditions and propose an annual pump maintenance program. The initial maintenance work will be done this fall and include installation of alarm systems.Mayor Thomas Ambrosino assured Sherman residents on Aug. 25 that the pump will be replaced or repaired, but warned two-dozen Sherman homeowners that permanent drainage improvements could take years to plan and pay for.That was scant consolation to residents like Roberta Ministeri who pumped sewage out of her basement following the Aug. 8 storm and resulting flood.Public Works Superintendent Donald Goodwin told residents during a City Council meeting on the flooding that insufficient drainage on Sherman allowed heavy rains to easily overwhelm the street’s pump.Councilors are also seeking city officials’ recommendations for improving drainage on Asti and Tuscano avenues and Eastern and Tapley avenues and Gore Road.Pump and tide gates are located on Martin Street and Arcadia Street – low lying areas with high water tables. A culvert collapse in another low lying area near the commuter rail tracks saddled the city with $900,000 in repair costs.Workers discovered the collapse in March 2007 near the tracks during construction of the Rumney Marsh Academy next to American Legion Highway.The collapse posed major problems for the city because the 24 inch-wide lines carried sewage from the eastern side of Revere, including Point of Pines, to pipe connections along Legion Highway.Contractors think the culvert was built on top of wood timbers and other debris and gradually sunk under its own weight into the unstable material.