Ko‘olau Mountains Watershed Partnership

Island of O‘ahu

On the island of O'ahu, the 99,000-acre Ko'olau Mountain Range is a vital natural resource, a place where the winds, land, plants and water converge in a symphony of natural beauty and interdependency. Its forested slopes shelter more than 80 rare or endangered native species and its streams and underground aquifers supply Oahu’s 953,000 residents with 133 billion gallons of fresh water each year.

The Ko`olau Mountains Watershed Partnership was formed in 1999 to protect these and other invaluable forest resources.

Our Approach

In 2000, the 4,534-acre O'ahu Forest National Wildlife Refuge, the first area within the Ko'olau Mountains formally protected for native species, was established by the Nature Conservancy and the U.S. Fish & Wildlife Service. Although the Conservancy does not own or manage lands in the partnership area, as an associate partner, it has played an active role in providing administrative and operational support and technical expertise to help build the emerging partnership. In 2002, the partnership completed a comprehensive management plan that proposed strategies and actions to accomplish its goal of protecting the forested watershed areas within the Ko'olau Range.

How the Partnership Will Help the Watershed

Primary threats to the Ko'olau watershed include invasive non-native plant species, feral ungulates and other non-native animals, human disturbances, aquatic pollutants and wildfire. The partnership has conducted biological, cultural and feral animal surveys, built  fencing enclosures around high-priority summit and drainage areas, and developed a strategy to control the spread of priority invasive weed species and ungulate populations in the watershed.


The following groups have worked together to understand and protect the rare and interdependent communities of plants and animals who live in this unique native ecosystem:

  • Agribusiness Development Corporation *
  • Bishop Museum *
  • Dole Food Company, Inc.*
  • Hawai`i Reserves, Inc. *
  • Hawai`i State Department of Hawaiian Home Lands *
  • Hawai`i State Department of Health
  • Hawai`i State Department of Land and Natural Resources *
  • Honolulu Board of Water Supply *
  • Kamehameha Schools *
  • Kualoa Ranch, Inc. *
  • Manana Valley Farm, LLC *
  • Nature Conservancy of Hawai`i
  • O`ahu County Club *
  • Pacific Cooperative Studies Unit
  • Queen Emma Land Company
  • Tiana Partners.*
  • University of Hawai`i Manoa, Lyon Arboretum *
  • U.S. Army *
  • U.S. Environmental Protection Agency
  • U.S. Fish & Wildlife Service *
  • U.S. Forest Service
  • U.S. Natural Resources Conservation Service
  • U.S. Geological Survey

*  Landowning partners


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