As part of the Coral Reef Project, the USGS is working closely with other local groups to investigate poor water quality issues in Maunalua Bay on the southeast coast of Oʻahu.
Overview

Oʻahu encompasses 1,546 sq km (597 sq mi) and is the third largest in the Hawaiian Islands chain. Also known as The Gathering Place, Oʻahu draws more visitors than any of the other Hawaiian Islands. The island was formed from joining of the Waiʻanae and Koʻolau volcanoes. Coral reefs surround the island, although active live coral growth is limited to the leeward sides of the island or in sheltered areas on the windward coasts. Reef structures on the north shore help form the waves that draw surfers worldwide.
Motivation
The USGS is working closely with Mālama Maunalua and the Kewalo Marine Laboratory, as part of the Hawaiʻi Local Action Strategy Plan, to investigate poor water quality issues in Maunalua Bay on the southeast coast of Oʻahu. This coral-lined embayment has seen a dramatic decline in ecosystem health, including sedimentation, invasive algae species, and a reduction in reef fish. A major factor in the decline of ecosystem health is human-induced changes on land, mainly from engineering of natural drainage gulches that have become concrete-lined channels. These channels speed up the flow of storm runoff from the uplands, increasing the discharge of freshwater, sediment and other land-based pollutants to the bay. The USGS has been instrumental in measuring water-column properties in Maunalua Bay, including waves, currents, water levels, temperature, salinity, and turbidity, to provide insight into the transport and fate of these contaminants.
We have also assisted the National Park Service (NPS) with documentation of underwater conditions around the USS Arizona Memorial (see World War II Valor in the Pacific National Monument) in Pearl Harbor. Of special concern is the fact that the hull of the USS Arizona is deteriorating and has the potential of releasing more than half a million gallons of fuel oil into the environment. By using the same instrumentation packages that we use to monitor oceanographic conditions on coral reefs, such as currents, waves, temperature and salinity, we can help the NPS get a handle on the physical dynamics surrounding the submerged hull.
Other partners working with the USGS on Oʻahu include the National Oceanic and Atmospheric Administration (NOAA), University of Hawaiʻi, James Cook University, University of California, Santa Cruz, and The Nature Conservancy.
The Hawaiian island of Oʻahu is just one of the USGS Coral Reef Project’s study locations.
Reef Hydrodynamics and Sediment Processes
Role of Reefs in Coastal Protection
Reef Resource Assessments - Planning for the Future
Hydrogeology and Reef Health
Climate Change and Land-use Histories
O‘ahu data sets produced by the Coral Reef Project
Projected flooding extents and depths based on 10-, 50-, 100-, and 500-year wave-energy return periods, with and without coral reefs, for the States of Hawaii and Florida, the Territories of Guam, American Samoa, Puerto Rico, and the U.S. Virgin Islands,
Below are publications associated with this project.
The value of US coral reefs for flood risk reduction
Rigorously valuing the role of U.S. coral reefs in coastal hazard risk reduction
Tropical cyclone projections: Changing climate threats for Pacific Island defense installations
Sources and dispersal of land-based runoff from small Hawaiian drainages to a coral reef: Insights from geochemical signatures
A Geochemical and Geophysical Assessment of Coastal Groundwater Discharge at Select Sites in Maui and O’ahu, Hawai’i
Coral calcification and ocean acidification
The effectiveness of coral reefs for coastal hazard risk reduction and adaptation
Mercury dynamics in a coastal aquifer: Maunalua Bay, Oʻahu, Hawaiʻi
Seafloor video footage and still-frame grabs from U.S. Geological Survey cruises in Hawaiian nearshore waters
Coastal circulation and potential coral-larval dispersal in Maunalua Bay, O'ahu, Hawaii—Measurements of waves, currents, temperature, and salinity, June-September 2010
From ridge to reef—linking erosion and changing watersheds to impacts on the coral reef ecosystems of Hawai‘i and the Pacific Ocean
The use (and misuse) of sediment traps in coral reef environments: Theory, observations, and suggested protocols
- Overview
As part of the Coral Reef Project, the USGS is working closely with other local groups to investigate poor water quality issues in Maunalua Bay on the southeast coast of Oʻahu.
Overview
Sources/Usage: Some content may have restrictions. Visit Media to see details.Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) image data of Oʻahu acquired January 13, 2010 Oʻahu encompasses 1,546 sq km (597 sq mi) and is the third largest in the Hawaiian Islands chain. Also known as The Gathering Place, Oʻahu draws more visitors than any of the other Hawaiian Islands. The island was formed from joining of the Waiʻanae and Koʻolau volcanoes. Coral reefs surround the island, although active live coral growth is limited to the leeward sides of the island or in sheltered areas on the windward coasts. Reef structures on the north shore help form the waves that draw surfers worldwide.
Motivation
Waikīkī from atop Diamond Head The USGS is working closely with Mālama Maunalua and the Kewalo Marine Laboratory, as part of the Hawaiʻi Local Action Strategy Plan, to investigate poor water quality issues in Maunalua Bay on the southeast coast of Oʻahu. This coral-lined embayment has seen a dramatic decline in ecosystem health, including sedimentation, invasive algae species, and a reduction in reef fish. A major factor in the decline of ecosystem health is human-induced changes on land, mainly from engineering of natural drainage gulches that have become concrete-lined channels. These channels speed up the flow of storm runoff from the uplands, increasing the discharge of freshwater, sediment and other land-based pollutants to the bay. The USGS has been instrumental in measuring water-column properties in Maunalua Bay, including waves, currents, water levels, temperature, salinity, and turbidity, to provide insight into the transport and fate of these contaminants.
We have also assisted the National Park Service (NPS) with documentation of underwater conditions around the USS Arizona Memorial (see World War II Valor in the Pacific National Monument) in Pearl Harbor. Of special concern is the fact that the hull of the USS Arizona is deteriorating and has the potential of releasing more than half a million gallons of fuel oil into the environment. By using the same instrumentation packages that we use to monitor oceanographic conditions on coral reefs, such as currents, waves, temperature and salinity, we can help the NPS get a handle on the physical dynamics surrounding the submerged hull.
Other partners working with the USGS on Oʻahu include the National Oceanic and Atmospheric Administration (NOAA), University of Hawaiʻi, James Cook University, University of California, Santa Cruz, and The Nature Conservancy.
- Science
The Hawaiian island of Oʻahu is just one of the USGS Coral Reef Project’s study locations.
Reef Hydrodynamics and Sediment Processes
As part of the USGS Coral Reef Project, the overall objective of this research effort is to better understand how circulation and sediment processes impact coral reefs and their adjacent coastlines.Role of Reefs in Coastal Protection
We are combining ocean, engineering, ecologic, social, and economic modeling to provide a high-resolution, rigorous, spatially-explicit valuation of the coastal flood protection benefits provided by coral reefs and the cost effectiveness of reef restoration for enhancing those benefits.Reef Resource Assessments - Planning for the Future
We are mapping and assessing all of the important geologic and oceanographic factors to identify those coral reefs most at risk and those reefs that are potentially the most resilient and the most likely to recover from natural and human-driven impacts.Hydrogeology and Reef Health
As part of the USGS Coral Reef Project, we are conducting geophysical and geochemical research to address questions about coastal groundwater-to-reef flow and coral reef health, with the goal of informing management decisions related to planning and implementing activities in priority watershed-coral reef systems.Climate Change and Land-use Histories
As part of the USGS Coral Reef Project, we are developing new and unique oceanographic and environmental archives from coral skeleton records to better understand the compounding effects of land-use and environmental change on coral reef health. - Data
O‘ahu data sets produced by the Coral Reef Project
Projected flooding extents and depths based on 10-, 50-, 100-, and 500-year wave-energy return periods, with and without coral reefs, for the States of Hawaii and Florida, the Territories of Guam, American Samoa, Puerto Rico, and the U.S. Virgin Islands,
This data release provides flooding extent polygons (flood masks) and depth values (flood points) based on wave-driven total water levels for 22 locations within the States of Hawaii and Florida, the Territories of Guam, American Samoa, Puerto Rico, and the U.S. Virgin Islands, and the Commonwealth of the Northern Mariana Islands. For each of the 22 locations there are eight associated flood mask - Publications
Below are publications associated with this project.
Filter Total Items: 20The value of US coral reefs for flood risk reduction
Habitats, such as coral reefs, can mitigate increasing flood damages through coastal protection services. We provide a fine-scale, national valuation of the flood risk reduction benefits of coral habitats to people, property, economies and infrastructure. Across 3,100 km of US coastline, the top-most 1 m of coral reefs prevents the 100-yr flood from growing by 23% (113 km2), avoiding flooding to 5AuthorsBorja G. Reguero, Curt Storlazzi, Ann E. Gibbs, James B. Shope, Aaron D. Cole, Kristen A. Cumming, Mike BeckRigorously valuing the role of U.S. coral reefs in coastal hazard risk reduction
The degradation of coastal habitats, particularly coral reefs, raises risks by increasing the exposure of coastal communities to flooding hazards. The protective services of these natural defenses are not assessed in the same rigorous economic terms as artificial defenses, such as seawalls, and therefore often are not considered in decision making. Here we combine engineering, ecologic, geospatialAuthorsCurt D. Storlazzi, Borja G. Reguero, Aaron D. Cole, Erik Lowe, James B. Shope, Ann E. Gibbs, Barry A. Nickel, Robert T. McCall, Ap R. van Dongeren, Michael W. BeckTropical cyclone projections: Changing climate threats for Pacific Island defense installations
Potential changing climate threats in the tropical and subtropical North Pacific Ocean were assessed, using coupled ocean-atmosphere and atmosphere-only general circulation models, to explore their response to projected increasing greenhouse gas emissions. Tropical cyclone occurrence, described by their frequency and intensity, near islands housing major U.S. defense installations was the primaryAuthorsMatthew J. Widlansky, Hariharasubramanian Annamalai, Stephen B. Gingerich, Curt D. Storlazzi, John J. Marra, Kevin I. Hodges, Barry Choy, Akio KitohSources and dispersal of land-based runoff from small Hawaiian drainages to a coral reef: Insights from geochemical signatures
Land-based sediment and contaminant runoff is a major threat to coral reefs, and runoff reduction efforts would benefit from knowledge of specific runoff sources. Geochemical signatures of small drainage basins were determined in the fine fraction of soil and sediment, then used in the nearshore region of a coral reef-fringed urban embayment on southeast Oahu, Hawaii, to describe sources and dispeAuthorsRenee K. Takesue, Curt D. StorlazziA Geochemical and Geophysical Assessment of Coastal Groundwater Discharge at Select Sites in Maui and O’ahu, Hawai’i
This chapter summarizes fieldwork conducted to derive new estimates of coastal groundwater discharge and associated nutrient loadings at select coastal sites in Hawai’i, USA. Locations for this work were typically identified based on pronounced, recent ecosystem degradation that may at least partially be attributable to sustained coastal groundwater discharge. Our suite of tools used to evaluate gAuthorsPeter W. Swarzenski, Curt D. Storlazzi, M.L. Dalier, C.R. Glenn, C.G. SmithCoral calcification and ocean acidification
Over 60 years ago, the discovery that light increased calcification in the coral plant-animal symbiosis triggered interest in explaining the phenomenon and understanding the mechanisms involved. Major findings along the way include the observation that carbon fixed by photosynthesis in the zooxanthellae is translocated to animal cells throughout the colony and that corals can therefore live as autAuthorsPaul L. Jokiel, Christopher P. Jury, Ilsa B. KuffnerThe effectiveness of coral reefs for coastal hazard risk reduction and adaptation
The world’s coastal zones are experiencing rapid development and an increase in storms and flooding. These hazards put coastal communities at heightened risk, which may increase with habitat loss. Here we analyse globally the role and cost effectiveness of coral reefs in risk reduction. Meta-analyses reveal that coral reefs provide substantial protection against natural hazards by reducing wave enAuthorsFilippo Ferrario, Michael W. Beck, Curt D. Storlazzi, Fiorenza Micheli, Christine C. Shepard, Laura AiroldiMercury dynamics in a coastal aquifer: Maunalua Bay, Oʻahu, Hawaiʻi
We evaluated the influence of groundwater–seawater interaction on mercury dynamics in Maunalua Bay, a coral reef ecosystem located on the south shore of Oʻahu, Hawaiʻi, by combining geochemical data with submarine groundwater discharge (SGD) rates. During a rising tide, unfiltered total mercury (U-HgT) concentrations in seawater increased from ∼6 to 20 pM at Black Point (west Bay) and from ∼2.5 toAuthorsPriya M. Ganguli, Peter W. Swarzenski, Henrieta Dulaiova, Craig R. Glenn, A. Russell FlegalSeafloor video footage and still-frame grabs from U.S. Geological Survey cruises in Hawaiian nearshore waters
Underwater video footage was collected in nearshore waters (AuthorsAnn E. Gibbs, Susan A. Cochran, Peter W. TierneyCoastal circulation and potential coral-larval dispersal in Maunalua Bay, O'ahu, Hawaii—Measurements of waves, currents, temperature, and salinity, June-September 2010
This report presents a summary of fieldwork conducted in Maunalua Bay, O'ahu, Hawaii to address coral-larval dispersal and recruitment from June through September, 2010. The objectives of this study were to understand the temporal and spatial variations in currents, waves, tides, temperature, and salinity in Maunalua Bay during the summer coral-spawning season of Montipora capitata. Short-term vesAuthorsM. Katherine Presto, Curt D. Storlazzi, Joshua B. Logan, Thomas E. Reiss, Kurt J. RosenbergerFrom ridge to reef—linking erosion and changing watersheds to impacts on the coral reef ecosystems of Hawai‘i and the Pacific Ocean
Coral reef ecosystems are threatened by unprecedented watershed changes in the United States and worldwide. These ecosystems sustain fishing and tourism industries essential to the economic survival of many communities. Sediment, nutrients, and pollutants from watersheds are increasingly transported to coastal waters, where these contaminants damage corals. Although pollution from watersheds is onAuthorsJonathan D. Stock, Susan A. Cochran, Michael E. Field, James D. Jacobi, Gordon TribbleThe use (and misuse) of sediment traps in coral reef environments: Theory, observations, and suggested protocols
Sediment traps are commonly used as standard tools for monitoring “sedimentation” in coral reef environments. In much of the literature where sediment traps were used to measure the effects of “sedimentation” on corals, it is clear from deployment descriptions and interpretations of the resulting data that information derived from sediment traps has frequently been misinterpreted or misapplied. DeAuthorsC. D. Storlazzi, M.E. Field, Michael H. Bothner - Partners