About Honolulu's Clean Water Program

The City and County of Honolulu's storm drain system is regulated under a National Pollutant Discharge Elimination System (NPDES) municipal separate storm sewer (MS4) permit. In 1990, the  Environmental Protection Agency (EPA) issued rules that required all municipalities with a population of over 100,000  to obtain NPDES permits for their storm drain systems. Honolulu has separate storm water and wastewater systems, unlike some older cities such as Boston and San Francisco, which have combined sewers that collect both wastewater and storm water. The EPA has delegated permitting authority  in Hawaii to the State Department of Health. The City first received its MS4 permit in 1994 for the  five -year period  from 1994 to 1999. The permit was renewed for another  five -year period in 1999.

On February 28, 2006, NPDES Permit No. HI S000002 was issued by the Hawaii Department of Health to the City and County of Honolulu.  The effective date is March 31, 2006 for another five-year period ending midnight, September 8, 2009.

The City's storm water permit requires it to develop and implement a storm water management program. The Department of Environmental Services is the lead agency.   The departments of Facility Maintenance, Planning and Permitting, and Design and Construction have key roles. The permit responsibilities of each department are described below.

The Department of Environmental Services is the lead agency and, through the Storm Water Quality Branch, administers the provisions of the City's NPDES storm water permit. It is responsible for public education/outreach, including the general public and targeted audiences such as construction contractors, backyard mechanics, and industrial areas; regulating certain nonstorm water discharges such as well drilling and hydrotesting discharges to the system; inspection of industrial activities; enforcement against illegal discharges and drain connections to the City's drain system; water quality monitoring; spill response and prevention; and coordination with other government agencies.

The Department of Facility Maintenance owns, operates, and maintains the municipal separate storm sewer system, which includes street sweeping, storm drain cleaning, roadside litter pickup, and maintenance of City-owned streams, channels, debris basins, and other structural Best Management Practices or BMPs, including the Kaneohe Dam and Kahaluu Lagoon. The City's system has more than 670 miles of pipes and culverts, 20,000 catch basins, and 8,000 manholes.

The Department of Planning and Permitting issues and administers zoning and land use changes, as well as the following permits: building, clearing and grubbing, stockpiling, grading, and construction dewatering. DPP issues private drain connection licenses to the municipal separate storm sewer system and assesses the need for construction of permanent detention/retention and other engineering control structures in large developments on a case-by-case basis. The department  takes enforcement action against illegal grading or construction.

The Department of Design and Construction manages all capital improvement projects done by the City, including plan preparation, funding and administering consultant and construction contracts, studies, designs, and construction management of flood control channels and structures.

For more information, please use the online form under contact us.