Plastic pollution is a global problem, but Hawaiʻi is especially exposed because the islands sit within major North Pacific currents that can carry marine debris from thousands of miles away. Local litter, stormwater, lost fishing gear, and debris transported across the Pacific can all contribute to what washes onto Hawaiian shorelines.
What Is Marine Debris?
NOAA defines marine debris as persistent manufactured or processed solid material that is discarded, disposed of, or abandoned in the marine environment or Great Lakes. It can range from large fishing nets and plastic containers to fragments that are only a few millimeters across.
Marine debris can enter the ocean in several ways:
- Land-based sources: litter, stormwater runoff, poor waste management, illegal dumping, and debris carried through rivers or drains.
- Ocean-based sources: lost or abandoned fishing gear, trash from vessels, aquaculture materials, and other items lost at sea.
- Disaster debris: material carried into the ocean by storms, floods, tsunamis, and other extreme events.
Why Hawaiʻi Is a Marine-Debris Hotspot
The Hawaiian Archipelago lies within the North Pacific Subtropical Gyre, a large system of circulating currents. NOAA describes Hawaiʻi as a hotspot for marine-debris accumulation because these currents can transport lost fishing gear and other debris from distant parts of the Pacific toward the islands.
This is especially evident in the Northwestern Hawaiian Islands, where remote reefs and shorelines receive debris despite having few or no local residents. Nets and other fishing gear can become entangled on reefs, threatening protected wildlife.
What About the Great Pacific Garbage Patch?
The Great Pacific Garbage Patch is commonly described as being between Hawaiʻi and California, but the name can be misleading. It is not a solid floating island of trash. NOAA describes it as a broad, shifting area where currents concentrate marine debris, much of it consisting of small plastic pieces dispersed throughout the water column.
Garbage patches also move with winds and currents, so there is no single fixed boundary that can be mapped like an island.
Plastic Pollution: Updated Facts
Older statistics such as “5.25 trillion pieces” remain useful as historical snapshots from particular studies, but they should not be presented as a current census of all ocean plastic. The amount, size distribution, and location of marine plastic are constantly changing.
How Marine Plastic Affects Wildlife and Coral Reefs
Marine debris can affect wildlife through entanglement, ingestion, habitat damage, and physical obstruction. Lost fishing nets are particularly damaging around coral reefs because they can snag, abrade, or smother living coral.
Sea turtles, seabirds, marine mammals, and fish may also ingest plastic fragments or become entangled in lines and nets. The severity of the effect depends on the type and size of debris, the species involved, and the circumstances of exposure.
Microplastics in Hawaiʻi's Marine Environment
As larger plastic items weather under sunlight, waves, and abrasion, they can fragment into smaller pieces. Microplastics can also originate from manufactured particles, synthetic fibers, and other sources.
Because microplastics are small, they can be consumed by marine organisms and can move through aquatic food webs. Scientists continue to study how particle size, polymer type, additives, and chemicals associated with plastic affect wildlife and human exposure.
For the drinking-water side of this topic, see our Microplastics in Drinking Water Guide.
Kamilo Beach and Tern Island: EPA's 2020 Impaired-Waters Decision
One of the most significant regulatory developments involving plastic pollution in Hawaiʻi occurred in 2020. Under Clean Water Act Section 303(d), EPA reviewed Hawaiʻi's impaired-waters list and determined that two waterbodies—Kamilo Beach on Hawaiʻi Island and Tern Island in the Northwestern Hawaiian Islands—should be added as impaired by trash.
EPA's final December 2020 action affirmed the addition of those two waterbodies to Hawaiʻi's 2018 impaired-waters list. Importantly, EPA described the impairment as trash pollution; the agency did not create a separate nationwide Clean Water Act category specifically for plastic pollution.
Where Does the Debris on Hawaiian Beaches Come From?
| Source | Examples | How It Reaches Hawaiʻi |
|---|---|---|
| Local land-based | Litter, storm drains, improperly managed waste | Wind, rain, streams, coastal runoff |
| Pacific-wide ocean transport | Plastic fragments, containers, consumer items | Currents and convergence zones |
| Fishing and maritime activity | Nets, line, floats, ropes, gear | Lost or abandoned at sea and transported by currents |
| Storms and disasters | Building materials, household objects, vessels | Flooding, waves, tsunamis, severe weather |
This mix is why it is misleading to attribute Hawaiʻi's marine-debris problem mainly to tourism or to local residents. Hawaiʻi receives debris generated locally, but it also intercepts material transported across the North Pacific.
What Is Being Done About Marine Debris in Hawaiʻi?
NOAA's Marine Debris Program, federal and state agencies, researchers, nonprofit groups, local communities, and volunteers conduct shoreline cleanups, fishing-gear removals, monitoring, education, and prevention projects throughout the Pacific Islands.
In the Northwestern Hawaiian Islands, large-scale removal projects focus heavily on derelict fishing nets and gear because these can damage coral reefs and entangle protected wildlife.
Cleanup is necessary, but prevention is equally important. Once plastic fragments into very small pieces, removing it from the ocean becomes much more difficult.
How Can We Reduce Plastic Pollution?
Individual actions cannot solve ocean plastic pollution on their own, but reducing unnecessary waste and preventing litter from entering waterways still matter. Practical steps include:
- Use reusable bottles, cups, bags, and food containers when practical.
- Avoid unnecessary single-use packaging.
- Dispose of fishing line and gear through appropriate collection programs.
- Secure trash so wind and rain cannot carry it into drains or waterways.
- Recycle only materials accepted by your local program.
- Choose durable products that can be repaired or reused.
- Participate in shoreline or stream cleanups.
- Support waste-reduction and marine-debris prevention programs.
Frequently Asked Questions
Why does so much marine debris wash up in Hawaiʻi?
Hawaiʻi sits within major North Pacific current systems that transport debris over long distances. Local litter and stormwater also contribute, but remote Hawaiian shorelines can receive substantial debris from elsewhere in the Pacific.
Is the Great Pacific Garbage Patch a floating island?
No. NOAA describes it as a large, shifting area where marine debris is concentrated by currents. Much of the material consists of small plastic pieces dispersed through the water rather than a solid surface layer.
Is most marine debris plastic?
Plastic makes up a major share of marine litter in many environments, but the composition varies by location. In parts of Hawaiʻi, derelict fishing gear can make up an especially important portion of large debris.
Did EPA declare Hawaiian waters impaired by plastic?
EPA added the waters at Kamilo Beach and Tern Island to Hawaiʻi's 2018 Clean Water Act impaired-waters list because of trash pollution. Plastic was an important part of the evidence, but the formal impairment category was trash.
Can microplastics enter the food web?
Yes. Small plastic particles can be ingested by marine organisms. Researchers continue to study how this affects individual species, ecosystems, and potential human exposure.
Final Thoughts
Hawaiʻi illustrates why marine debris is both a local and international problem. Waste generated on land can reach the ocean through runoff and poor disposal, while lost fishing gear and other debris can travel across the Pacific before washing ashore on distant islands.
The most effective response combines prevention, improved waste management, reduced unnecessary plastic use, fishing gear recovery, cleanup, monitoring, and international cooperation. Cleanup can remove large debris from beaches and reefs, but preventing waste from reaching the ocean is ultimately more effective than recovering it after it has dispersed.