New Maui Rain Garden to Promote Pollution Prevention, Driver Safety

HWY-M’s completed rain garden. Red ti leaves from the garden will be used along state highways on Maui to promote driver safety. PC: State of Hawaii, Department of Transportation, Highways Division – Maui District.

The creators of a new rain garden in Kahului are planning to grow multiple benefits from it for Maui’s community and the environment.

The State of Hawaiʻi, Department of Transportation, Highways Division – Maui District (HWY-M) has completed construction of a rain garden at its office near Kahului Airport. The project funnels rainwater from HWY-M’s office rooftop to nourish a garden planted with native foliage, and will be used to support the state Highway Division’s ongoing efforts to safeguard Maui’s environment and promote highway safety.

“Rain gardens are landscaped areas irrigated by stormwater that’s collected and channeled from impervious surfaces like gutters and pavement,” said Ty Fukuroku, program manager, HWY-M Environmental Management. “In our case, stormwater that falls on our office roof is diverted to our garden where it waters our red ti plants and seeps into the ground instead of just emptying out into the parking lot.”

Stormwater that falls or drains onto impervious surfaces like asphalt and cement can pick up litter and other pollutants in its flow path. Because stormwater is not filtered, any pollutants in it may eventually end up in local streams, ponds and the ocean. As a permanent best management practice, rain gardens can decrease the amount of stormwater that flows over land, helping to conserve water, prevent flooding and keep pollution out of the environment.

As part of its ongoing public awareness efforts, HWY-M will be installing educational signage and sharing stories online about its new garden, how rain gardens work, and how they can help protect stormwater.

“Our project was a little more complex because of the preexisting gutter system, but rain gardens are generally easy to construct, and we hope homeowners and businesses will consider creating their own rain gardens to help reduce the amount of stormwater runoff from their property,” Fukuroku said.

HWY-M will also be putting its rain garden to use to promote driver safety on the state highways. Red ti leaf from the garden will be placed at the locations of fatalities along the state right-of-way, to serve as a remembrance for the lives lost, and a reminder to motorists to drive safely.

HWY-M’s new rain garden was built with the assistance of MauiScapes, a professional landscaping company that helped install and connect pipes from the office building’s gutter system to the rain garden. Rainwater from the rooftop now flows into underground pipes that run through the garden beds.

For more information about protecting Maui’s stormwater, visit stormwatermaui.com.

Perforated pipes were installed underground to channel stormwater from HWY-M’s roof into the garden, where the water will infiltrate the soil and hydrate the plants. PC: State of Hawaii, Department of Transportation, Highways Division – Maui District.