Stormwater Regulations

The primary Australian Standard for stormwater drainage is AS/NZS 3500.3 — Plumbing and Drainage: Stormwater Drainage. This standard specifies the methods for calculating the required gutter and downpipe sizes based on the roof area, the local rainfall intensity, and the building location. It also sets requirements for overflow provisions, sub-soil drainage, and connection to the public stormwater system. In Victoria, compliance with AS/NZS 3500.3 is required under the Building Regulations and is verified by the plumbing inspector. Local councils across Gippsland may impose additional stormwater management requirements, particularly for new developments. These can include on-site stormwater detention (OSD) tanks to limit the peak discharge rate from the site, rainwater tanks for reuse, and water-sensitive urban design (WSUD) measures. When replacing a roof, the opportunity to upgrade the gutter and downpipe system to current standards should be considered, particularly if the existing system is undersized or non-compliant. Town & Country Roofing ensures all gutter and downpipe installations comply with AS/NZS 3500.3 and any applicable local council requirements. This includes correctly sizing gutters and downpipes for the roof catchment area, providing adequate overflow provisions, and ensuring connection to approved stormwater discharge points. For properties in areas with specific stormwater management requirements, Town & Country Roofing can coordinate with plumbers and hydraulic engineers as needed.