Hawaii, an isolated island state, faces unique pressures in managing the volume of waste generated by its resident and visitor populations. The state’s reliance on imported goods means nearly all consumer products ultimately become discards that must be managed within a finite space. Sustainable waste management is a complex endeavor for protecting the delicate island ecosystems, especially since the waste stream is significantly higher per capita than the mainland United States.
Current Waste Disposal Infrastructure
The approach to handling Municipal Solid Waste (MSW) in Hawaii is highly dependent on the county and its geography. On O‘ahu, home to the majority of the state’s population, the primary method for processing MSW is the Honolulu Program of Waste Energy Recovery, known as H-POWER. This Waste-to-Energy (WTE) facility incinerates approximately 691,000 tons of solid waste annually, generating electricity for the island’s power grid.
While H-POWER reduces the volume of waste by roughly 90%, the process produces residual ash and non-combustible waste that must be disposed of in a landfill. O‘ahu’s main repository is the Waimanalo Gulch Sanitary Landfill (WGSL), which faces a strict deadline for closure. The State Land Use Commission mandated that the City and County of Honolulu must close the WGSL by March 2, 2028, creating an urgent need for a replacement location or an alternative processing solution.
In contrast, the neighbor islands primarily rely on landfilling for MSW disposal. Maui County manages waste at the Central Maui Landfill (CML), which is currently undergoing expansion to secure capacity. Kaua‘i County utilizes the Kekaha Landfill, which is pursuing vertical expansion to extend its operational life. Hawai‘i County, or the Big Island, consolidates its waste at the Pu‘uanahulu landfill, which has capacity estimated to last for decades due to its size and lower population density. This differing infrastructure highlights the decentralized nature of waste management, where each county manages its own disposal.
Recycling and Material Diversion Efforts
To reduce reliance on final disposal, Hawaii operates several programs designed to pull materials out of the waste stream. One successful program is the statewide bottle deposit program, known as HI-5. This program places a redeemable 5-cent deposit on most beverage containers 68 ounces or less, including glass, plastic, and aluminum.
The HI-5 system has achieved a high redemption rate, capturing a large percentage of deposit-eligible containers. Curbside recycling is also offered across the islands, typically collecting materials like cardboard, paper, non-deposit plastic containers (types #1 and #2), and metal cans. These materials are aggregated and prepared for shipment off-island, a necessity due to the lack of sufficient local processing infrastructure.
Diversion strategy also focuses on organic waste, which takes up substantial landfill space. Hawai‘i County, for example, diverts approximately 40,000 tons of green waste annually for processing into mulch. Recovered materials, including aluminum, glass, plastic, and paper, are exported to the mainland U.S. and Asia. This reliance on global markets means that the economics and environmental oversight of Hawaii’s recycling are subject to international policies and shipping costs.
The Unique Geography of Island Waste Management
The nature of being an archipelago creates fundamental challenges for waste management that mainland regions do not face. Geographical isolation means almost all consumer goods must be imported, creating a constant, high-volume waste stream that is expensive to manage. This dependency is compounded by the high cost of exporting recovered materials back across the Pacific Ocean to reach processing facilities and end-markets.
The high cost of shipping severely limits the economic viability of recycling, especially for lower-value materials like mixed paper and certain plastics. Logistics are sometimes mitigated by using the unused “backhaul” capacity of shipping containers that would otherwise return to the mainland empty. This allows for the export of recyclables at a lower marginal cost, though the overall price remains a barrier to developing local markets.
The physical constraint of limited land means that landfill capacity is a perpetual political and environmental concern. While Hawai‘i County has significant space, the densely populated island of O‘ahu is struggling to secure a site to replace the imminent closure of its major MSW landfill. This finite space necessitates a high degree of efficiency in waste reduction.
The tourism sector further complicates the waste stream by generating a disproportionately high volume of refuse. On the Big Island, the tourism industry accounts for over 10% of the island’s total waste generation. Furthermore, Hawaii’s location makes it an unintended recipient of marine debris, with an estimated 15 to 20 tons of ocean trash washing up on its shores annually. This influx of plastic from the North Pacific gyre requires specialized, ongoing cleanup efforts separate from the daily management of MSW.
Future Goals for Waste Reduction and Sustainability
The state and its counties are actively pursuing goals to reduce waste and enhance long-term sustainability. Many counties have adopted “Zero Waste” targets, aiming to divert nearly all discarded materials from landfills through reduction, reuse, and recycling strategies. These goals are supported by legislation that focuses on source reduction.
A major focus has been on mandating reductions in single-use plastics and packaging. For example, the City and County of Honolulu enacted a comprehensive ban on single-use plastic foodware, including straws, utensils, and polystyrene foam containers. Similar measures have been implemented across other counties, creating a strong statewide push to eliminate materials difficult to recycle locally and prone to becoming marine debris.
There is a growing effort to invest in local processing infrastructure to reduce the reliance on exporting materials. This includes exploring advanced technologies like anaerobic digestion and expanding composting facilities to handle organic waste, a major component of the waste stream. Furthermore, the state is considering Extended Producer Responsibility (EPR) programs, which would legally require manufacturers to manage the end-of-life cycle of their products, incentivizing them to design for durability and recyclability.