Watershed Forest Area

By 2030, protect 30 percent of watershed forests.

Approximately 20% of land area in the Hawaii Islands is identified as priority watersheds [843,000 acres]. In 2011, only 10% of these priority watersheds were protected (90,000 acres). Since then, watershed protection efforts have accelerated and currently, approximately 17% are under a high level of protection and the target is to reach 30%. This dashboard explains how we can Protect, Connect, Prevent Wildfire and Respect these irreplaceable forests.


Priority watersheds under high level protection are defined as upland native forests that are fenced from non-native hooved animals (pigs, goats, deer, sheep, and cattle). These non-native animals trample and eat plants, spread invasive weeds, cause erosion, and foul streams with waste and sediment. These areas are also where intensive weed control and native plantings are focused. Step overs and gates allow continued hiking access into public fenced areas. These protected areas exist across private, Federal, and State lands that are managed collectively through watershed partnerships.

Native forests play a critical role to provide our statewide freshwater supply by acting like a “sponge” and absorbing rainfall and cloud moisture. When a native forest is damaged, so is its ability to capture water. For example, widespread invasive strawberry guava demands 27% - 53% times more water than native forests, causing extensive water loss across landscapes. In East Hawaii, invasive plants have reduced estimated groundwater recharge by 85 million gallons a day. That is enough water to fill 130 Olympic sized swimming pools with fresh water every day. If not protected, conversion to non-native forest in these priority areas would generally result in loss of recharge function, decline in water supplies, and an increase in runoff.



Hunters are a valuable partner in watershed conservation by helping to control hooved animals in watersheds throughout the state. Hunting provides local food and a way to carry on family traditions. Hunting and hiking also provide exercise, local jobs and tourism revenue, and are activities that connect people with nature, fostering a culture of sustainability that is central to the Aloha+ Challenge.

The Department of Land and Natural Resources, Division of Forestry and Wildlife (DOFAW) provides 900,000 acres of public hunting lands and over 855 miles of trails and access roads. Most of the land managed by DOFAW is open for public hunting, and DOFAW is working across the State to establish new hunting lands and access corridors through partnerships with private landowners and purchasing new lands (Map Coming Soon). The proposed Game Management Advisory Commission will advise DOFAW on goals to improve the hunting experience and which lands are long-term sustainable hunting priorities.



Wildfire presents a large threat to our watersheds and management is costly. The percentage of land area burnt in Hawaii is on average greater than the percentage of area burnt in the entire U.S. mainland or the 12 western states, where wildfire is a major threat (see Figure 1). Native Hawaiian plants are not adapted to wildfire, and after they are burned they are typically replaced by weeds that are more prone to re-burn. This creates a cycle of wildfires. It is important to raise awareness of wildfire risk, as over 98% of wildfires are caused by humans (see Figure 2 for location of wildfire incidents). In addition, continued investment in weed control and native species restoration can reduce wildfire risk as nonnative grasses and shrubs are more prone to wildfire (See Native Species). We also need to manage fuel loads in fire-prone areas.

Figure 1: Wildland Fires in Hawaiʻi, 2017 (Source: PFX Annual Summary).

Figure 2: Location of Wildfire Incidents

Source: Hawaii Wildfire Management Organization 2014

Figure 3: Vegetation types burned by the 16 largest fires of 2018 (Source: PFX Annual Summary).

Figure 4: The annual area burned as a percentage of total land area in Hawaii (black bars) was on par or exceeded the 12 western-most states of the United States, including Alaska (light gray bars), and the United States as a whole (dark gray bars) for all years in the 2005 – 2011 period except 2011 (WMFI 2012). The years 2005, 2006, 2007, 2011, and 2012 (not shown) were the worst wildfire years on record for the continental United States in terms of total area burned.

Source: Clay Trauernicht & Hawaii Wildfire Management Organization

Figure 5: Hawaii Wildfire Acres Burned By Island. *Data unavailable for Molokai and Lanai.

Source: Hawaii Wildfire Management Organization



Since the first Hawaiians encountered these islands, the forests have been the wellspring of physical and spiritual nourishment. Within these forests, the plants and animals have their own significance, individually revered as manifestations of gods, or used for medicines, offerings, or other material needs. The plants and animals, regarded as elders and ancestors, evolved unique identities when they arrived and intertwined with the landscape and life forms of Hawaii (Visit Native Species). The extinction of the unique inhabitants of the upland forests of the wao akua unravels the spiritual, as well as material vitality of Hawaii. Like water, they are irreplaceable.

Land-based citizen science can help assist large-scale projects across the islands. Beginning in 2016, a Kailua-based program relied on community volunteers to go out and collect inventory data on trees growing around the neighborhood. Today, this program has gained momentum with over 5,600 trees logged and mapped in Kailua and over 1,100 trees mapped in Honolulu. View the interactive map below to see which species have so far been classified.
Figure 6: The map above displays trees measured across Oahu. This “Tree-Mapper” provides information surrounding citizen science data collected. (Source: Citizen Forester ProgramTreePlotter Map)


There are many other efforts underway to protect Hawaii’s watersheds mauka to makai (from the mountain to the sea). Activities such as acquiring land for conservation, restoring stream banks, and erosion control practices help increase recharge in the lower urbanized watershed and prevent land-based sources of pollution from entering into the ocean. Hawaii Green Growth, in partnership with the Hawaii Conservation Alliance, will be completing a community mapping survey to gather data on watershed initiatives mauka to makai for watershed protection and restoration. To learn more or to participate contact christin@hawaiigreengrowth.org.

The stewardship mapping and Assessing Project (STEW-MAP) aims to strengthen community capacity to care for Hawaii’s land and water resources. Through this initiative, STEW-MAP harbors a public stewardship database and visually displays geographic map data of groups that mālama ʻāina. In its initial phase, STEW-MAP focuses on stewardship commitments from Moanalua to Kualoa Ahupuaʻa land divisions, but aims to include more in the future.
Figure 7 & 8: Phase 1—Moku boundaries on Oʻahu, and ahupuaʻa boundaries derived from the Moku boundaries in Figure 7.
Source: STEW-Map


In 2011, DLNR estimated it would require $11 million in annual state funding to double the area of priority watersheds protected in ten years, which would lay the foundation for achieving the 2030 goal of tripling the areas protected. This plot (Figure 5) represents state funding for watershed protection initiatives since 2013 as an indicator of trends in watershed funding. In order to meet the 2030 goal, more funding is needed. The chart includes State funds allocated to the Division of Forestry and Wildlife's Watershed Partnership Grants Program, as well as General Obligation Bonds for Watershed Protection. It does not include State funds for other forest protection programs as well as the County, Private, and Federal funding that contributes to watershed forest protection. 

Figure 5: Hawaii Watershed Initiative State Funding. The red dashed line highlights the funding required to meet Natural Resource goals.

Source: Department of Land and Natural Resources

Watershed Snapshots
Pictured below are interactive maps of watersheds from the Hawaiʻi Conservation Alliance. These maps detail annual rainfall, subsistence fishing areas, fish catch and biomass, as well as a snap shot of current managed areas within the community.

Haʻena Watershed Snapshot Map

Hauula to Punaluu Watershed Snapshot Map

Figure 6 & 7: The above ArcGIS maps above display the watersheds in both the Haʻena Watershed and watersheds. Some of the data reflected on these maps include subsistence fishing areas, fish biomass, and rainfall from years 2010 to 2016. (Source: HCA)

Maunalua Watershed Snapshot Map

Figure 8: The map to the left shows a snapshot of the Maunalua Watershed. Data reflected on this map includes information on fishponds and springs, wetlands, & fish biomass from 2010 to 2016.
Source: Hawaiʻi Conservation Allliance (HCA)
Figure 9: The conservation map pictured above shows the Conservation Communities and maps where management activities range from Ecology and Freshwater Resources, and historical imagery. (Source: HCA).

Learn More and Make a Difference

What You Can Do

  1. Join in the effort of protecting Hawaiian watersheds by learning about various volunteer activities with Conservation Connections
  2. Learn about watersheds and how to help
  3. What you can do to reduce or stop nonpoint source pollution

More Information

  1. Learn more about Hawaii’s Department of Land and Natural Resources Watershed Plan: “ The Rain Follows the Forest- Hahai nō ka ua i ka ululāʻau"
  2. Learn more about the history of water use in Hawaiʻi
  3. Learn more about protecting our forests from wildfire

SDG 6 - Clean Water and Sanitation
Ensure access to water and sanitation for all
SDG 12 - Responsible Consumption and Production
Ensure sustainable consumption and production patterns
SDG 14 - Life Below Water
Conserve and sustainably use the oceans, seas and marine resources
SDG 15 - Life on Land
Sustainably manage forests, combat desertification, halt and reverse land degradation, halt biodiversity loss
SDG 17 - Partnerships for the Goals
Revitalize the global partnership for sustainable development