Koʻolau Mountains Watershed Partnership — Corporate Water Replenishment Fence Project (Hawaiʻi, USA)

The Koʻolau Mountains Watershed Partnership (KMWP), founded in 1999, unites 17 landowning partners and 10 associate partners — including the State of Hawaiʻi, Kamehameha Schools, the U.S. Army and the Honolulu Board of Water Supply — to manage more than 100,000 acres of public and private land across Oʻahu's Koʻolau range, a system that supplies roughly 90% of the island's potable water through aquifer recharge.

Protect priority native forest from invasive species to safeguard aquifer recharge for the Waiawa/Pearl Harbor aquifer system, which delivers more than 364 million gallons of water a day, in support of Hawaiʻi's state goal of protecting 30% of its priority watersheds by 2030.

In April 2017, a $200,000 Coca-Cola Foundation grant — matched by $100,000 from the Honolulu Board of Water Supply and $100,000 in state watershed capital-improvement funds — financed a 6.6-mile fence enclosing 1,400 acres of priority forest (1,000 acres of Kamehameha Schools land and 400 acres of the state's ʻEwa Forest Reserve) to exclude feral pigs, goats and invasive plants.

No independently published before/after data on invasive-species density or aquifer recharge specific to this fence exists. KMWP staff describe a "significant positive impact" over ten years in qualitative terms rather than with monitored metrics. The corporate-utility-state co-funding model has since been replicated by other watershed partnerships coordinated under the Hawaiʻi Association of Watershed Partnerships.

The fence protects a critical component of Oʻahu's aquifer-recharge infrastructure, but it is one element of a much larger, longer-running partnership rather than a standalone, separately evaluated intervention, and its specific impact has not been independently measured.