Overview

Study Goal and Objectives

The overall goal of the Māmala Bay Study (1993-1996) was to develop a water quality management plan for Māmala Bay off the South Shore of Oʻahu in Hawaiʻi. To achieve this goal, the study had to provide a sound scientific basis for selecting appropriate actions to protect and enhance the environmental quality of Māmala Bay. This required meeting at least the following specific objectives:

1. To collect, collate, and organize all relevant basic data and scientific information on factors affecting the environmental quality of Māmala Bay;
2. To identify locations and characterize quantities and qualities of all important point and non-point sources of pollution to Māmala Bay and to determine their relative contributions as functions of seasonal changes in surface runoff and wastewater discharges through outfalls;
3. To obtain a quantitative description of hydrodynamics of the interaction between wastewater plumes discharged from ocean outfalls and the ambient ocean environment, including a description of density structure in the initial mixing zones at the Sand Island and Honouliuli outfalls;
4. To obtain a quantitative description of the three-dimensional ocean current system of Māmala Bay, including seasonal variability of drift and wind-driven currents, tidal effects on currents, and oceanographic mechanisms affecting transport, dilution, and dispersion of polluting substances in Māmala Bay;
5. To characterize microbiological components of the polluting wastewaters, using techniques to quantify concentrations of indicator organisms and pathogens, and to assess the viability and persistence of human pathogenic bacteria and viruses in the ocean environment;
6. To simulate the transport and fate of polluting substances and microorganisms (bacterial and viral pathogens) of sewage origin in the ocean environment and to estimate the potential for exposure by contact with contaminated water in areas of recreational use;
7. To estimate the concentration of disease-producing microbiological organisms in discharges from point and non-point sources, and to assess their persistence in the ocean environment and potential transport to receptors;
8. To assess risks to public health by exposure to contaminated ocean waters;
9. To determinate impacts of wastewater discharges on indigenous aquatic flora and fauna, including potential changes in the benthic habitat; and
10. To develop alternatives for improvement of water quality in Māmala Bay and guidelines for monitoring the efficacy of implemented management strategies.

Study Setting

For the purposes of the Study, Māmala Bay included all ocean areas from Diamond Head to Barbers Point, Oʻahu. The study area extended offshore of the Bay coastline and included all ocean waters and point sources of pollution that could directly impact the quality of the near-shore aquatic environment. In addition, the study area extended a sufficient distance inshore of the coastline to include significant non-point sources that could affect the quality of near-shore waters. These included sources within the Māmala Bay watershed such as the Ala Wai Canal. The limits of the study area and locations of different sampling sites are shown in the map above.

Reports

These Māmala Bay Study reports were prepared in order to document in detail the scientific investigations conducted during the course of the study (1993-1996), and to present the conclusions and recommendations of the Commission, which are documented in a series of technical reports, MB-1 through MB-10. Chapter MB-1, prepared by the Māmala Bay Study Commission, describes the background for the study, the charge to the Commission, the specific objectives of the study and its organization, and brief descriptions of the various projects and responsible contractors. Chapters MB-2 through MB-10, MB-11A, MB-SP2, and MB-SP4 present the results of investigations contracted by the Commission, authored by the responsible principal investigators, each with their independent conclusions and recommendations. Chapter MB-11, Water Quality Management for Māmala Bay, was prepared by the commissioners themselves, drawing on results of contracted studies and the counsel of principal investigators. Conclusions and recommendations are those of the Commission alone.

Data Sets

The purpose of this study is to observe the physical, chemical, biological, and geophysical nature of Māmala Bay, Oʻahu, Hawaiʻi and surrounding areas in an effort to detect influences from point and non-point source pollution. The table below contains multiple interdisciplinary datasets—refer to NOAA National Oceanographic Data Center (NODC) Accession ID numbers under the Data column for further details.

Acknowledgments

The Māmala Bay Study Commission is pleased to acknowledge the contributions of the many individuals and agencies that have facilitated this first comprehensive investigation in the concept of Integrated Coastal Management. We especially wish to express our appreciation to our able assistants, Ms. Camilla Saviz, Shino Tanikawa, Jeanne Gulnick, and Dr. William Straube, for their invaluable expeditious and conscientious attention to the many technical and administrative details of the study. It could not have been completed in a timely manner without their dedication.

Our local office in Honolulu functioned throughout the study period due to the prompt and courteous attention of our local assistants in Honolulu, Ms. Julie Cone, Andrea Ferst, Veronica Carreira, and Dawn Burton who responded to the many public inquiries and requests for information about the study. We wish to express our most sincere appreciation to the Hawaiʻi Community Foundation, especially to Ms. Janet Oshiro and Ms. Janis Reischmann, for the efficient management of the fiscal and administrative activities of the study.

During the course of the study the Commission received the expert advice and counsel of specialists in various relevant fields. Drs. William Eichbaum and Robert Knecht contributed from their experience with Integrated Coastal Management; Drs. Ian Kind, Donald Pritchard, Donald Harleman, Frederick Pfaender, Anne Summers, Gordon McFeters, and John Largier provided guidance on different expert review panels for oceanography, modeling, and microbiological techniques.

Various agencies provided valuable information and assistance to the Commission during the course of the study. The Commission wishes to acknowledge in particular the cooperation and assistance of the Department of Oceanography of the University of Hawaiʻi at Mānoa (UH), Dr. Roger Fujioka, Ms. Kimberly Roll, and the Water Resources Research Center at UH for hosting and coordinating MB-7 project teams, the Sea Grant College Program at UH, the United States Navy and Coast Guard for their cooperation in field programs, the National Oceanographic and Atmospheric Agency (NOAA), and the State of Hawaiʻi Department of Health for making available useful data and information on Māmala Bay. The Commission gratefully acknowledges assistance provided to field programs conducted during the course of the study by persons and groups, including Edward K. Noda and Associates, the staff at American Workboats, and the captains and crews of M/V Holokai, the M/V American Contender, and the R/V Kila. The cooperation of the City and County of Honolulu, in particular Mr. Ross Tanimoto, in providing access to records of wastewater treatment plant performance and field survey information is also much appreciated. The enthusiastic assistance and support provided by many individuals and organizations was instrumental in successful completion of the Māmala Bay Study.