Rainwater Harvesting Without Accidentally Building a Frog Hotel

Rainwater harvesting is wonderfully practical. It can support gardens, flushing, cleaning and, with proper treatment, some household uses. But a tank is not a magic purity barrel. Without screens, first-flush control and maintenance, it can become a very enthusiastic biology project.

Keep debris out

Gutter guards, leaf screens and first-flush diverters prevent roof dust, leaves and bird souvenirs from becoming tank ingredients.

Store it properly

Use sealed tanks, protected inlets, overflow screens and opaque materials to reduce algae growth. Sunlight plus nutrients equals green soup.

Treat for the intended use

Garden water needs less treatment than drinking water. If humans will consume it, test it and consider sediment filtration, carbon, UV and possibly finer treatment depending on results.