Plumbing - Fact Sheets Backflow Prevention Devices(PDF, 153KB)Decommissioning Septic Tank/s(PDF, 203KB)House Drainage Plans(PDF, 266KB)On-site Sewerage Facility(PDF, 241KB)On-site Sewerage Facility - 'OSF' Maintenance(PDF, 216KB)Plumbing and Drainage(PDF, 258KB)Waterless Composting Toilets(PDF, 293KB)