Drinking water guidelines typically require higher water quality than most reuse applications – such as gardening, irrigation, toilet flushing and vehicle wash bays.
Advanced filtration, disinfection and water quality monitoring are costlier processes that facilitate may facilitate the use of stormwater as a potable water source. These processes provide specialised treatment modalities to counteract stormwater pollutants, which can include bacteria, nutrients, hydrocarbons, chemicals and heavy metals.
Harvested stormwater provides cheaper alternatives to municipal water supplies – lowering reliance on potable water and reducing water bills. However, for typical applications, captured stormwater is not treated to meet requirements for human consumption on most sites.
Roof Harvested Rainwater vs. Stormwater
Roof-harvested rainwater is a cheaper consideration for potable water, typically implemented in locations where ‘town’ water supplies are unavailable. This runoff does not interact with the same range of contaminants as stormwater that flows across site surfaces such as lawns, roads, driveways, paths and hardstand, which makes it easier to manage water quality and contamination effectively.
In their guide for Rainwater Tanks, NSW Health states that ‘a properly maintained rainwater tank can provide good quality drinking water. Providing the rainwater is clear, has little taste or smell and is from a well-maintained water catchment system it is probably safe and unlikely to cause any illness for most users.’
‘Water used for household purposes for drinking, food preparation or bathing should meet water quality guidelines in order to protect you and your family’s health. The water should be free of harmful microorganisms or harmful levels of chemicals.’
Pollution removal capabilities to adapt stormwater harvesting for drinking require the design of stormwater harvesting tanks alongside appropriate treatment infrastructure. These systems necessitate higher operating costs but cater to areas with scarce potable water supply. However, this harvested water is less cost-effective for most site uses, such as gardening and irrigation.
Atlan Stormwater can help design and implement comprehensive stormwater harvesting configurations – and can assist you in selecting assets for storing stormwater or roof-harvested rainwater to manage your on-site water quantity, water quality and sustainability requirements.
