Skip to main content

DNRP's 2015 Greenhouse Gas Emissions Sources

DNRP's 2015 Greenhouse Gas Emissions Sources

While DNRP creates greenhouse gas emissions, it also helps remove and reduce emissions through strategies including:

Recycling 21,000 MTCO2e

Recycling at transfer stations

21,000 MTCO2e removal from recycling more than 18,000 tons of cardboard, metals and other resources.

What’s the benefit?
Recycling reduces GHGs created by mining, farming or manufacturing new products. At the Solid Waste Division's recycling and transfer stations, DNRP is increasing recycling rates through customer education, developing new systems to support recycling, and through staff redirecting recyclable materials incorrectly disposed of by customers.

How do we calculate it?
DNRP's approach uses the widely accepted U.S. Environmental Protection Agency's (EPA) Waste Reduction Model. The recycling strategies used at DNRP's transfer stations are above and beyond industry best practices and are rapidly increasing recycling at the transfer stations. For example, the total quantity of materials recycled between 2014 and 2015 increased by 33 percent.

Loop Biosolids 37,000 MTCO2e

Loop Biosolids

37,000 MTCO2e removal associated with productive reuse of 26,000 metric tons of Loop Biosolids

What’s the benefit?
Loop Biosolids are an endlessly renewable resource that are byproducts of wastewater treatment. Loop Biosolids are soil amendments that replace synthetic fertilizers, add carbon to soils, and increase photosynthesis in plants and trees to store carbon.

How do we calculate it?
There is no existing GHG offset protocol for the carbon removal and GHG reduction benefits associated with wastewater biosolids. DNRP's approach is based on direct measurements from forest and agriculture sites where Loop Biosolids have been applied and on peer review scientific research published by University of Washington and Washington State University scientists.

Tree planting 114,000 MTCO2e

Tree planting

114,000 MTCO2e removal associated with planting 41,000 trees

What’s the benefit?
DNRP has numerous tree planting efforts, including volunteer tree planting program, plantings on King County Parks lands, and as part of salmon recovery and streamside restoration projects. Trees sequester carbon in their plant material as the grow and take in CO2 from the atmosphere. The department has been planting tens of thousands of trees per year for the last several decades.

How do we calculate it?
DNRP's approach is conservative and consistent with other local best practices, including the accounting approach used by Forterra's Evergreen Carbon Capture Program. It is based on estimates of carbon stored in each tree 100 years after it is planted, while taking into account a conservative estimate that only about one quarter of trees planted will survive to that age.

Energy production 10,000 MTCO2e

Renewable energy production at the South Plant Wastewater Treatment Plant.

10,000 MTCO2e removal based on the production of 180,000 MMBTU of pipeline quality renewable biogas

What’s the benefit?
South Plant processes biogas and uses a portion of this energy to fuel boilers and make electricity used on site. The rest of the pipeline-quality biogas is sold and injected into the local natural gas pipeline. The generation, use, and sale of biogas reduces the amount of energy the department needs to purchase and also replaces fossil fuel natural gas used by residents and businesses with this renewable energy source.

How do we calculate it?
This GHG removal assumes that South Plant’s biogas displaces fossil fuel gas usage and uses an emission factor for fossil fuel natural gas to estimate the GHG benefit.

Total 2015 GHG Emissions Removals: -182,000 MTCO2e

Additional DNRP GHG Reductions

Beyond these GHG removals and reductions, DNRP provides other important services that help reduce regional GHG emissions. These actions are not currently included in DNRP's Beyond Carbon Neutral for several reasons, such as complexity in accounting and shared ownership of the actions and benefits.

  • Its Regional Trail System that supports an alternate transportation network throughout the county;
  • Green building programs that encourage using recycled, sustainably created or resource-conserving building materials;
  • Supporting locally grown food and farmland preservation.
  • Forest protection and growth. Carbon dioxide is taken from the atmosphere through trees and shrubs, including the forestlands and open spaces that are protected through conservation easements and prevent urban sprawl.
expand_less