Mauka-to-makai efforts aim to protect critical Maui reef
Groups work to carry out restoration projects in along the coastline
With new data and partnerships, a coalition of organizations are proposing several restorative projects for the watersheds along the Olowalu reef, which is considered one of the “most essential reefs” to protect on Maui.
Going region by region, The Nature Conservancy is working with the National Oceanic and Atmospheric Administration, the state Department of Land and Natural Resources’ Division of Aquatic Resources, Maui Nui Marine Resource Council, as well as county, state and private landowners, and community members, to identify restoration actions to “stop the bleed” and ultimately reduce land-based inputs to the coral reef ecosystems near Olowalu.
Sediment runoff, sea level rise, floods, wildfires, axis deer and other issues have long threatened Olowalu.
However, there’s “an awful lot of excitement” surrounding the efforts that are underway to restore the coastal area, TNC environmental engineer Kim Falinski said during the marine council’s Know Your Ocean Speaker Series last month.
Falinski presented “The Vision for Olowalu-Ukumehame-Papalaua,” which includes healthy coastal and land ecosystems.
For this project, the marine council, TNC and West Maui Ridge to Reef Initiative’s Hui O Ka Wai Ola water quality testing program provided data and aerial images to pinpoint source points of sediment and soil erosion along the four-mile stretch of road that runs parallel to the Olowalu reef system, which has helped to produce mitigative action plans for the upcoming decade.
In 2017, the 939-acre reef was declared an official Mission Blue Hope Spot — a category of places that are critical to the health of the ocean. Research has shown that this area in West Maui is very biodiverse and an important source of larvae for other habitats in Maui Nui waters, according to the marine council.
Historically, much of the plains in Olowalu and Ukumehame were used for growing food, so Falinski said they’d like to see the lower wetlands thrive again through mauka-to-makai best practices.
“As you drive by, there’s definitely still vegetation indicators,” said Falinski, adding that restoring the wetlands is an opportunity to buffer and/or capture sediment before it hits the coastline. “As soon as you start taking your vegetation cover off, it exposes the surface to a rate that is so much higher than it once was.”
Even though Ukumehame is the largest watershed by area and has some of the highest turbidity in the coastal zone, specifically at Ukumehame Park, it’s not actively eroding like the smaller watersheds along the Pali, such as Papalaua/Manawaipueo.
Geochemical analysis using fire and combustion signatures identified many “hot spots” along the Pali, showing sediment runoff smothering critical reef areas, she said. There’s also unused retention areas across the landscape that could be recovered and used as buffers to hold sediment, too.
About 750 of the total 13,800 acres of Olowalu-Ukumehame-Papalaua are high priority for implementing action plans, Falinski said.
At Manawaipueo, next to the Papalaua Beach parking lot, the TNC team along with the county Parks and Recreation Department and Public Works Department plans to redesign the culvert and parking lot to hold more sediment; restore native forests and vegetation mauka, as well as install firebreaks; and do fire prevention.
“We have to take care of the land so that we don’t have problems in the long run,” she said. “We hope to work on these county-owned areas more often along with the state-owned areas above.”
In Papalaua Gulch, where the beach park has the second-highest turbidity levels, some proposed interventions include redesigning the retention basin, controlling the axis deer with fencing and doing headcut (a steepened area of a stream where erosion can occur) stabilization in partnership with DLNR’s Division of Forestry and Wildlife and the Mauna Kahalawai Watershed Partnership.
Farther down at Ukumehame and the lower wetlands, TNC is collaborating with the Department of Transportation on the $22-million Honoapiilani Highway Realignment project and understanding the environmental consequences of rising tides.
“We see an opportunity of protecting the wetlands a little bit better if the road wasn’t right there,” she said.
There’s also a decommissioned reservoir mauka of the highway, which can be used as it once was for lo’i, she added.
Dune restoration is among other possibilities for Ukumehame.
For Olowalu, some ideas include coral restoration, riparian zones (vegetation on the edge of bodies of water) and partnering with Kipuka Olowalu in restoring lo’i and other indigenous agriculture in the area.
This is something that the nonprofit has already been “leading the way” on as far as educating the community on how to have healthy water and riparian systems, said Falinski.
TNC’s Emily Fielding, also a member of the Hui O Ka Wai Ola water quality testing program, hopes to get some of these solutions into the pipeline for planning, costs and funding requests within two years, but the timeline of implementation is unknown and dependent on each project and partnerships.
“Some are lower hanging fruit more than others,” Fielding said.
There’s a lot of moving parts, but the desired long-term outcome is to form a collaboration with landowners, government partners and local groups who want to invest in and commit to funding and implementing these types of actions to protect and restore the Olowalu reef, Fielding said.
“Not only is Olowalu a seed reef for other coral reefs around Maui Nui, it’s also home to the oldest coral in the main islands of Hawaii,” said Amy Hodges, the marine council’s programs and operations manager, in a news release. “Protecting this reef is vital, and we’re excited to hear what TNC and other stakeholders are doing to preserve this unique reef.”
* Dakota Grossman can be reached at firstname.lastname@example.org.