Recycling and Landfill Diversion

The data in the chart above presents the annual quantity of waste (in tons) that is processed through recycling, waste-to-energy or landfilling for the most recent four (5) calendar years (2007 – 2011).

Brief analysis: The data shows how Oahu’s waste has been diverted from landfill through recycling and waste-to-energy. The general trend shows annual increases in recycling and waste-to-energy, and decreases in landfill disposal. In comparing the most recent years, 2008 to 2011, note that overall waste generation decreased significantly, most likely due to the down-turn in the economy. Total waste generation dropped from 1.8 million tons in 2008 to 1.5 and 1.6 million tons in subsequent years. Although recycling tonnages appear to remain somewhat flat until 2011, the recycling rates, or percentage of the total waste stream, has increased proportionally. The total landfill diversion rate continued to increase from 57 percent (2007) to 66 percent (2011), with continued reductions of waste disposed in landfill.

Total waste includes all waste of all types disposed/recycled on Oahu, including construction and demolition waste. There are two landfills on Oahu: the City’s Waimanalo Gulch Sanitary Landfill (WGSL), which is designated for MSW, and the private PVT Landfill, which is permitted for construction and demolition waste only. When analyzing municipal solid waste (MSW) only and landfill diversion specific to the WGSL, the landfill diversion rate achieved through recycling and waste-to-energy is almost 73% and the general material recycling rate is 38% For a fuller comparison of diversion rates for WGSL over the most recent five (5) years, see the chart below.

Note that the general material recycling rate (shown in the darker blue) increased from 33 percent (2007) to more than 38 percent (2011).

For a breakdown of Oahu's waste by type and tonnage, see the 2006 Waste Characterization Study. For a further discussion of projections for 2013, see future plans.

Recycling data: The tables below provide detail of what was recycled by material type. The City has gathered annual recycling data since 1988 (except for 1989 and 1990). Note the upward trend of general material recycling from approximately 75,000 tons in 1988 to well over 400,000 tons today. Recycling of construction and demolition materials, such as concrete, rock and asphalt, has added between 100,000 to 200,000 tons to the recycling rates. These C&D recycling rates tend to fluctuate based on the volume and type of construction projects undertaken from year to year.

Yearly Recycling Rates (tons)