Safe Drinking Water Branch

The Underground Injection Control (UIC) program serves to protect the quality of Hawaii’s underground sources of drinking water from chemical, physical, radioactive, and biological contamination that could originate from injection well activity.

Underground Injection Wells are wells used for injecting water or other fluids into a groundwater aquifer. Department of Health Administrative Rules, Title 11, Chapter 23 provides conditions governing the location, construction, and operation of injection wells so that injected fluids do not migrate and pollute underground sources of drinking water. Section 4 of the Rules gives the criteria for classifying aquifers into those that are designated as underground sources of drinking water and those that are not.

The boundary between exempted aquifers and underground sources of drinking water is generally referred to as the “UIC Line”. Restrictions on injection wells differ, depending on whether the area is inland (mauka) or seaward (makai) of the UIC line.

The UIC Maps show the areas inland and seaward of the UIC line on all major islands. These maps are meant for general informational purposes only. The Department holds the official UIC maps containing detailed information about the UIC Line. For more information, contact the Safe Drinking Water Branch’s UIC Program.

Submit UIC On-line Application

UIC Maps of Hawaiian Islands

Underground Injection Wells are wells used for injecting water or other fluids into a groundwater aquifer. Department of Health Administrative Rules, Title 11, Chapter 23 provides conditions governing the location, construction, and operation of injection wells so that injected fluids do not migrate and pollute underground sources of drinking water. Section 4 of the Rules gives the criteria for classifying aquifers into those that are designated as underground sources of drinking water and those that are not.

The boundary between non-drinking water aquifers and underground sources of drinking water is generally referred to as the “UIC Line”. Restrictions on injection wells differ, depending on whether the area is inland (mauka) or seaward (makai) of the UIC line.

The UIC Maps show the areas inland and seaward of the UIC line on all major islands. These maps are meant for general informational purposes only. The Department holds the official UIC maps containing detailed information about the UIC Line. For more information, contact the Safe Drinking Water Branch’s UIC Program.

To use the maps below, use the navigation tools to zoom to your area of interest. Click on the map to find the UIC Code for that location:

UIC line as line

UIC line as polygons

BELOW (makai) UIC LINE

• Underlying aquifer not considered drinking water source
• Wider variety of wells allowed
• Injection wells need UIC Permit or Permit Exemption
• Permit limitations are imposed

ABOVE (mauka) UIC LINE

• Underlying aquifer considered drinking water source
• Limited types of injection wells allowed
• Injection wells need UIC Permit or Permit Exemption
• Permit limitations are imposed and requirements are more stringent

Contact Us

Phone: (808) 586-4258
Fax: (808) 586-4351
E-Mail: [email protected]

• Oahu
  Safe Drinking Water Branch
  Environmental Management Division
  Hawaii State Department of Health
  2385 Waimano Home Road, Suite 110
  Uluakupu Building 4
  Pearl City, HI 96782-1400
• East Hawaii
  Safe Drinking Water Branch – Hilo
  Hawaii District Health Office – Hilo
  1582 Kamehameha Avenue
  Hilo, Hawaii 96720
  Phone: (808) 933-0401
  Fax: (808) 933-0400

Last Update: 10 April 2021