A works approval under section 19A(1)(a) of the Act or a licence under section 20(1)(a) of the Act is not required with respect to discharges or deposits to land or water from the following—
(a) an enclosed drain connected to a sewer;
(b) a municipal stormwater drainage system;
(c) an emergency relief structure or other installations in the sewers of a sewerage authority;
(d) an effluent reuse scheme or activity which meets discharge, deposit and operating specifications acceptable to the Authority.