It is unlawful and a public nuisance for any person to construct or connect any leader, drain, basin, pipe or other conduit used for carrying off rain, storm or surface water, so as to, directly or indirectly, connect the same with or permit rain, storm or other surface water to flow into any sanitary sewer of the city. (Ord. 1056 NCS §1, 1972; Ord. 317 NCS §5; prior code §19.3.)