Stormwater network

Rain falls onto roofs, driveways, roads, and other hard surfaces and becomes stormwater. Stormwater runoff is collected in a rain tank (1) for storage and reuse, while other runoff enters sumps, bubble-up sumps, catch pits and drains (2). Some stormwater is directed to a soak pit (3), where it infiltrates into the ground and helps recharge or replenish the groundwater.

During rainfall, runoff also travels across the land along overland flow paths (4), which provide a natural pathway for stormwater and help convey water when rainfall exceeds the capacity of stormwater systems.

Stormwater enters stormwater pipes (5) through catch pits and drains. Some stormwater passes through a rain garden (7), where soils and vegetation help filter contaminants and reduce the amount of runoff entering the system.

Stormwater is conveyed through pipes and streams, including beneath roads via a road culvert (6), before ultimately discharging to receiving waters, including major streams, rivers and the ocean (8).