State Environmental Planning Policy (Housing) 2021

All stormwater collected as a result of the erection of, or alterations or additions to, a group home or an ancillary structure must be directed by a gravity fed or charged system to—

Note—

All stormwater drainage systems and connections to public drainage systems or inter-allotment drainage systems must either be approved under the Local Government Act 1993, section 68 or comply with the requirements for the disposal of stormwater contained in the development control plan that is applicable to the land.