The Mayor, Chief of Police, Superintendent of Public Works and/or such other officers as may be subject to the direction of the Mayor and designated by him for such purpose, shall make inspections and investigations or cause inspections and investigations to be made from time to time to determine whether any condition exists or any activity is being engaged in which constitutes a valid nuisance, and such officer shall make or cause to be made an inspection and investigation upon complaint being made by any responsible person.