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History of Wastewater in Hawaii

100 Years of Wastewater Treatment on Oahu


  • Kakaako Pump Station built in 1901
  • Wahiawa Wastewater Treatment Plant, Oahu's first treatment plant, built in 1928
  • Sugar dominated the economy, cesspools dotted the landscape
  • Oahu's population: less than 40,000


The Kakaako Pump Station on Ala Moana Boulevard stands as a reminder of days when wastewater systems on Oahu were simple and basic.  Construction on the initial sewer system gravity flow to a low point began in 1899 when the population was relatively low, life was agrarian and concern for wastewater's impact on the environment had yet to emerge.  For decades, untreated waste was collected in cast iron pipes and discharged into the ocean just a half-mile off shore.

            On April 29, 1925, the Legislature, by Act 150, created a special commission of five appointed members by the Governor known as the Honolulu Sewer and Water Commission.  Honolulu instituted the act to meet the public health emergency by authorizing the construction of needed sewer and water improvements by special commission with funds provided by a bond issue.

            The City issued bonds valued at $6 million with about 60 percent going towards improvements to the Honolulu Water Works system and 40 percent designated to the sewer system.

            In 1927, the Commission started the construction of two high-level intercepting sewers Kalihi Interceptor on School Street and Manoa-Kaimuki Interceptor on Wilder Avenue.

            Mayor George Fred Wright proposed a five-year, $10 million program dedicated to public works in 1936 with about half of it spent on extensions of the inadequate sewer system.



In 1940 and 1941, the Chamber of Commerce sponsored a sanitary survey of the waters between Diamond Head and the Kewalo sewer outlets.  This led Samuel W. Tay, then Director of Sanitation of the Territorial Board of Health, to conclude that sufficient evidence obtained showed "the need of providing treatment of the sewage before discharging it into the sea" in order to protect the recreational beaches and water.


1950s & 1960s

  • Electric trolleys gave way to diesel-powered buses
  • Tourism-based growth created infrastructure demands
  • Treatment plants built in Kailua (1965) and Waianae (1968)
  • Oahu's population: app. 350,000


1950s Population Boom

The jet age rise in tourism and a growing economy increased demands on wastewater capacity.  A series of individual systems appeared along the coast.  Septic tanks and cesspools became widespread with the post-World War II housing boom.  Control systems were expanded and upgraded in what was basically an island decentralized telemeter system.



  • The Federal Water Pollution Control Act of 1948 was the first major U.S. law addressing water pollution.  Growing public awareness and concern for controlling water pollution led to sweeping amendments in 1972.  As amended in 1977, the law became commonly known as the Clean Water Act (CWA).
  • Honolulu's largest WWTP opened at Sand Island in 1978; Honouliuli followed in 1980
  • Oahu's population: app. 630,000


1970s Federal Standards

Over the years, Oahu's wastewater collection system developed in response to an ever-expanding population.  Hawaii's water pollution control program began in the late 1960s and was codified in 1973.  As the population grew, so did national awareness about damage to the environment and risks to public health were reaching dangerous levels. Result:  the Federal Clean Water Act of 1977.  The Sand Island WWTP, Oahu's largest, opened the following year.



  • Kahuku, Paalaa Kai and Kailua facilities built in 1980
  • City plans 20-Year Sewer Rehabilitation Program
  • Microcomputer wastewater monitoring system installed
  • City began processing sludge into compost from Honouliuli
  • Synagro In-vessel Bioconversion Facility built to handle Sand Island sludge


21st Century Technology

Oahu's wastewater treatment system is a mix of high technology, hard work and professional commitment.  Nearly 400 people oversee and operate sophisticated treatment plants, computerized data systems, biological laboratories, deep-sea research and the ongoing construction and repair of 2,100 miles of wastewater lines.  Public outreach on these operations has become important with the realization of the role we all play in pollution control.


The federal government became much more active in the regulation of the discharge of sewage.  The National Environmental Policy Act (NEPA) was signed into law Jan. 1, 1970.  This led to the creation of the Environmental Protection Agency in December 1970 to regulate pollution control programs for air, water and solid wastes.  The Water Pollution Control Act Amendments of 1972 increased the federal government's role in water pollution control.


Historic Legislation Aimed at Controlling Water Pollution

Rivers and Harbors Act:  Passed in 1899

This was first piece of legislation passed in the United States aimed at protecting surface water from pollution.  This law prohibited the discharge of refuse into navigatable waters.


Federal Water Pollution Control Act:  Passed in 1948

Required polluters, such as factories and sewage treatment plants, to pretreat their effluents to reduce pollution.


Water Quality Improvement Act:  Passed in 1970

This legislation provided for the authorization of major spills.  This law was passed in response to numerous oil spills.


Clean Water Act:  Passed in 1972
Primary Federal Law that governs the discharge of pollutants into the nation's waterways.

Consists of the 1972 Federal Water Pollution Control Act and subsequent amendments

Credited with reducing the amount of polluted waterways by close to half, slowing destruction of wetlands, and funding the construction of sewage treatment plants

The Clean Water Act consists of two general parts:
1. Regulation of pollution discharges into waterways with the goal of making the surface water "fishable and swimmable"

  • Environmental Protection Agency sets water quality standards for surface water contaminants
  • Industries must treat discharge and municipal treatment plants must provide secondary treatment
  • Requires anyone who discharges pollutants directly into surface water to obtain a permit
  • U.S. Army Corp of Engineers issue permits for wetlands development
  • U.S. Department of Agriculture is responsible to minimize runoff from farms
  • National Oceanic and Atmospheric Administration helps protect coastal waters

2. Federal government's grant program to help cities build wastewater treatment plants

  • From 1972 to 2000, the federal government provided $69 billion for treatment plants, and state and local government spent an additional $25 billion.
  • In 1996, the EPA released reports projecting the need for an additional $139.5 billion in projects over the next 20 years.


Last Reviewed: Thursday, September 19, 2013