2025 Annual Impact Report
Protecting Maui’s Waters, Mauka to Makai
From Mauka to Makai: Connecting Land and Sea for Maui’s Reefs
Maui’s coral reefs do not exist in isolation. What happens on the mountain eventually reaches the ocean. Fertilizer applied to a lawn, wastewater injected into the ground, sediment loosened by rain; All of it finds its way to the coast, and all of it leaves a mark on the reefs below. This is the reality that shapes everything MNMRC does.
In 2025, that mauka to makai thread ran through every program we led. We helped a Lāhainā community restore a gathering place with reef-friendly plants. We completed coast-wide limu surveys, tracking nutrient pollution from South to West to North Maui. We continued building three years of reef monitoring data in South Maui. And we established the island’s first Community-Based Coral Restoration Area, giving damaged corals a second chance.
The connections are real, between land and sea, between communities and conservation, between the work we do today and the reefs we hope to see tomorrow. Mahalo to our community of volunteers, sponsors and partners, we couldn’t do this without you.
Reef-Friendly Landscaping
In 2025, MNMRC partnered with Kahoma Village residents to restore a beloved community gathering space damaged by the Lāhainā wildfire. Nearly 200 volunteers planted 100 native and resilient plants across 19 varieties, while incorporating compost tea, biochar, and other reef-friendly landscaping practices. Together, these efforts are helping reduce erosion and chemical runoff while creating a renewed place for community connection, education, and healing.
Explore our Reef-Friendly Landscaping Program and Certifications →
Hui O Ka Wai Ola: 10 Years of Water Quality Monitoring
Ten years of community-based monitoring have created one of Hawaiʻi’s most comprehensive records of nearshore water quality. Since 2016, Hui O Ka Wai Ola has collected more than 5,500 samples along leeward Maui. The decade of data reveals that turbidity exceeds state standards at every monitored site, nitrate levels frequently exceed standards, and salinity is rising coastwide. These findings show where Maui’s coastal waters are most stressed and help guide solutions that protect our reefs and communities.
Explore the findings with Liz Yannell, Director of Hui O Ka Wai Ola, in our Know Your Ocean Speaker Series, or dive deeper into the full 10-year report.
Tracking Nutrient Pollution with Limu
Limu can reveal what is happening in our coastal waters by absorbing and storing nitrogen from sources such as fertilizer and wastewater. In 2025, MNMRC sampled 72 sites across South, West, and North Maui, identifying areas affected by wastewater injection wells, locations with signatures consistent with fertilizer runoff, and sites requiring further investigation. This growing coast-wide dataset helps connect land-based pollution with reef health and guides future mitigation efforts.
Community-Based Coral Restoration
MNMRC established South Maui’s first Community-Based Coral Restoration Area off Waipuʻilani Beach Park in 2025. Working with Kuleana Coral Restoration, the State of Hawaiʻi Division of Aquatic Resources, and local community members, our team reattached 60 corals that had already broken from the reef. By giving these “corals of opportunity” a second chance to survive, the project is helping restore coral cover while building a community-driven model for reef stewardship.
Discover how community-based coral restoration is giving damaged corals a second chance →
Long-Term Reef Monitoring
MNMRC’s long-term monitoring program helps reveal how South Maui’s reefs are changing and where intervention is most urgently needed. Over three years, our team analyzed more than 189,000 points of reef data across eight sites. The findings show meaningful differences between reef areas, but also a consistent challenge: turf algae covers nearly half of the seafloor at most sites, while the grazing fish that help control it remain persistently low.
Maui Nui Marine Resource Council is a 501(c)(3) charitable organization.
Your donation is US tax-deductible to the extent allowed by law.
EIN: 47-2509441
Maui Nui Marine Resource Council
P.O. Box 331204, Kahului, HI 96733
(808) 707-5056