Making The Best Of Windward Rains

The Gomes family home in Enchanted Lake now has its own rain garden, with these proud installers standing by its side: (from left) Hui o Ko’olaupoko project coordinator Annie Lovell, and homeowners Maria, Paul and Lorna Gomes. Photo from Annie Lovell.

What began for Hui o Ko’olaupoko as one sample rain garden at He’eia State Park has grown into eight residential and two public demonstration gardens across Windward Oahu.

“For Hawaii, it’s a relatively new type of stormwater management project that we’re trying to get going here,” said program coordinator Annie Lovell.

A rain garden is a shallow depression lined with rocks, compost and plants, built in areas that experience high volumes of runoff flow. They are designed to collect this water and filter out pollutants before they can reach streams or the ocean, thus improving water quality.

Water quality is a big issue in Windward, given the 36,000 housing units in Ko’olaupoko, most of them impervious — meaning that rainwater runs right off roofs and driveways without being reabsorbed into the ground.

“Although the amount of water going off one residential property may not seem like a lot,” Lovell said, “when it’s multiplied out over the thousands of homes we have on island, this results in severe degradation of water resources.”

HOK came up with rain gardens as one of many easy ways for homeowners to combat the problem.

Grants last year from U.S. Environmental Protection Agency and the state’s Clean Water Branch, Polluted Control Runoff Fund, allowed the nonprofit organization to fund at least 50 rain gardens through its Rain Garden Co-op & Cost Share Program.

The goal, Lovell explained, is to target a rain garden for one property, and then invite that homeowner’s neighbors, friends and family to come help build it, hoping it will catch on and multiply, once they see how useful and aesthetically pleasing the gardens are.

So far, it’s working. Six of the residential rain gardens were created in the past five months, and there’s a waiting list for more. A Lanikai installation, for example, generated requests from at least two neighbors to do the same.

To learn more, email info@huihawaii.org. HOK staff will inspect the site and, if viable, will work with the homeowner throughout the process, from manpower to material costs.

Volunteers also are welcome. For general information, visit hui-hawaii.org or order a copy of the group’s rain garden manual to read up on it.