By Corlyn Orr
Hālau Kū Māna Public Charter School is located in Makīkī Valley, where according to The Rainfall Atlas of Hawai‘i, the mean annual rainfall measures approximately 53 inches per year. With so much rainfall, teachers at Hālau Kū Māna have long talked about installing a rooftop rainwater harvesting system to teach their students about water conservation and to promote sustainability practices.
As part of the USGBC Green Apple Day of Service, Craig Patterson of C & C Waterworks along with staff from the Hawai‘i State Energy Office and HHF Planners worked with Hālau Kū Māna to install two rainwater harvesting systems at the school. Each system consists of a large storage tank that collects rainwater from the rooftop gutters. The school will use the captured rainwater to water their gardens and lawns, which will help to conserve water and reduce water costs. Mahalo to Craig of C & C Waterworks for sharing your expertise and knowledge in installing the systems and for volunteering your time and materials to the project. Mahalo also to Gail Suzuki-Jones and Fifa Anistia of the Hawai‘i State Energy Office for helping to move the tanks and dig trenches to bury the pipes. (Wasn’t relocating the two 300-gallon plastic tanks easy in comparison to setting the 1,500 gallon tank into place?)
Besides water conservation, rain water harvesting can also be valuable for stormwater and flood control management. By collecting the runoff, catchment systems allow the earth to replenish and soak up some groundwater instead of being flooded or overrun, which in turn prevents the pollution of streams and oceans (Hint: The University of Hawai‘i’s College of Tropical Agriculture & Human Resources website is a good resource).
In my efforts to organize this project for Hālau Kū Māna, I learned that roughly 600 gallons of water can be collected from a 1,000 square foot rooftop for every 1 inch of rainfall. After watching Craig Patterson install the tanks at Halau Ku Mana and reading about the environmental benefits of rain barrel water catchment, I am inspired to install a rain barrel at home.
To see how you can install your own rain barrel catchment at home, check out the Honolulu Board of Water Supply’s website.
Learn about the University of Hawai‘i’ CTAHR Hawaii Rainwater Catchment Systems Program here.
See our blog about last year’s Green Apple Day event at Hālau Kū Māna.
Corlyn Orr is an HHF Associate who believes that planning is about inspiring actions that create a better future for Hawai‘i’s keiki. Besides maintaining her professional responsibilities as a land use and environmental planner, she is dedicated to learning one new thing every day, appreciating sunsets and the ocean around us, and acquiring gratitude and grace.