An owner shall ensure that: The disposal of filter backwash water and pool or spa wastewater conforms with: COMAR 09.20.01; Local sanitary code requirements; and Discharge requirements of COMAR 26.08.01—26.08.04; and Deck drainage disposal conforms with: COMAR 09.20.01; and Local plumbing code requirements. An owner may not return filter backwash water or other wastewater to a pool or spa, except for filter backwash water that has been filtered to remove particulates and treated to eliminate coliform bacteria and waterborne pathogens.