In a unanimous vote on Monday, Quincy city councilors approved a much-anticipated update to the city’s Hazard Mitigation Plan. The plan, which requires updating every five years, specifies projects that would reduce the consequences of hazardous events. The council began reviewing the plan in 2011, but federal approvals slowed the process. The plan also authorizes the city to spend $1.4 million in federal grants, which will be used for two flood-management projects, including drainage improvements in the Circuit Road/Spence Avenue area, and installation of a tide gate at Sagamore Creek. “[This is] a significant matter for all of us here in the city, particularly for residents in Wards 2 and 3, where flooding has been a hazard,” said City Councilor Kevin Coughlin.