Hydrologic Units

Early efforts to update the Commission’s Water Resource Protection Plan (WRPP) highlighted the need for surface water hydrologic units to delineate and codify Hawaii’s surface water resources. Surface water hydrologic units served as an important first-step towards improving the organization and management of surface water information that the Commission collects and maintains, including diversions, stream channel alterations, and water use.

In June 2005, the Commission adopted the report on surface water hydrologic units and authorized staff to implement its use in the development of information databases in support of establishing IFS. The result is a surface water hydrologic unit code that is a unique combination of four digits.

The Stream Protection and Management (SPAM) Branch is currently working to develop and compile information summaries for specific surface water hydrologic units. Some of the areas that the Commission is actively working on are identified below. Please check back as these information summaries will be posted as they are completed. The hydrologic units below are organized by island and unit code.

Island of Oahu

  • 3016: Punaluu
  • 3017: Kahana
  • 3022: Waikane
  • 3024: Waiahole

Island of Maui

  • 6001: Waikapu
  • 6004: Ukumehame
  • 6005: Olowalu
  • 6006: Launiupoko
  • 6007: Kauaula
  • 6008: Kahoma
  • 6009: Wahikuli
  • 6010: Honokowai
  • 6011: Kahana
  • 6012: Honokahua
  • 6013: Honolua
  • 6014: Honokohau
  • 6022: Waihee
  • 6023: Waiehu
  • 6024: Iao
  • 6034: Honopou
  • 6037: Hanehoi
  • 6047: Waikamoi
  • 6048: Puohokamoa
  • 6049: Haipuaena
  • 6050: Punalau
  • 6051: Honomanu
  • 6052: Nuaailua
  • 6053: Piinaau
  • 6054: Ohia
  • 6055: Waiokamilo
  • 6056: Wailuanui
  • 6057: West Wailuaik
  • 6058: East Wailuaiki
  • 6059: Kopiliula
  • 6060: Waiohue
  • 6061: Paakea
  • 6062: Waiaaka
  • 6063: Kapaula
  • 6064: Hanawi
  • 6065: Makapipi