Provides that the police commissioner of any police department in a city having a population of one million or more shall not substantially alter the boundaries of police precincts, once fixed, or close, remove or relocate a police stationhouse unless at least thirty days prior to the date such action shall take effect, written notice of such action has been given to each local community board or board having jurisdiction over that part of the city directly affected by such proposed alteration, closure, removal or relocation.