Rain is a free, renewable source for water. With proper storage and treatment, you can harvest rainwater for many indoor and outdoor tasks. Most harvesting systems collect rainwater via roof gutter runoff and store it in a tank. Before installing any harvesting equipment, consult with a local official in case your state has any restrictions. Then use this beginner’s guide to learn about safe rainwater harvesting. 

How to Safely Use Roof Gutters to Collect Water

1. Add Filters 

Install a filter at the end of the main downspout to keep debris like leaves and twigs from entering your tank. Add a second, finer filter closer to your tank to catch any remaining particles. Clean all filters at least once a week or more often during seasons of heavy rain. On a day without rain, remove and rinse the filters before re-installing. 

2. Don’t Let It Sit 

Standing water is a breeding ground for bacteria, mosquitoes, and other organisms. Clean your tanks or barrels at least once a week or in between rainfalls during heavy seasons. Empty the contents, bleach the insides, then rinse the tank multiple times to get all the chemicals out.

You can also add a tablespoon of oil to the water to prevent mosquito nests. The oil will stay at the surface, and you can use the rest of the water below. 

3. Don’t Drink It 

Even with proper care, rainwater can still have contaminants that may make you sick. Stick to non-drinking uses for harvested rainwater, such as watering your garden or compost, washing your car or indoor appliances, and flushing your toilets. 

Make sure your roof gutters can handle rainwater harvesting with maintenance from Gutter King. Located in Waialua, they are Hawaii’s go-to choice for gutter cleaning, repair, or installation. This full-service rain gutter company has been operating for over 20 years to earn their sterling reputation. Learn more about their rain gutters online, or call (808) 621-5115 to make an appointment.