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King County is taking action to protect people and property from the increasing risks associated with climate change and decreasing the carbon emissions that fuel it.

We are making investments in climate solutions like transit, open space protection, and clean fuels that have significant benefits for mobility, health, recreation, and quality of life.

Executive Constantine's regional approach to confronting climate change unites cities, businesses, nonprofits, and universities. He also has multiple King County departments coordinating efforts on climate change, including Natural Resources and Parks, Public Health, Transportation, and Emergency Management.


Through the King County-Cities Climate Collaboration (K4C), Executive Constantine has brought together city leaders who represent three-quarters of the County’s population to agree to ambitious goals to reduce carbon emissions.

We’ve mapped out shared commitments to actions needed to achieve these goals in the areas of transportation, growth management, energy efficiency, renewable energy, green building, waste reduction, recycling, and agriculture.

K4C partners support projects and programs in areas such as green building, using and producing renewable energy, sustainability outreach and education, and alternative transportation.

All King County cities are encouraged to join into this effort.


In our region today, cars and trucks are the primary sources of carbon emissions. That's why Executive Constantine has made improving regional mobility an integral part of his climate change strategy.

Metro Transit is an industry leader in expanding the use of green technology in public transportation and proudly operates one of the greenest bus fleets in the nation. About 70% of our fleet is either hybrid or electric, and we are on track to have an all hybrid and electric fleet by 2018. Metro received gold-level recognition in 2013 from the American Public Transportation Association for significant reductions in energy, water use, and waste.

Metro will soon be testing fast-charge battery-electric buses. These zero-emission buses can travel about 23 miles on a 10-minute charge and will save the fleet energy and money. A battery-charging station has already been set up at the Eastgate Park-and-Ride, with more planned soon.


Executive Constantine announced in February 2015 a two-year pilot project that will make King County the largest government in the U.S. to use the same energy tracking system that Microsoft uses to reduce energy in its smart buildings.

The software will be installed at five County buildings and provide maintenance staff with real-time analytics that help them operate the facilities more efficiently, identify HVAC problems faster, and better prioritize maintenance work. The goal is for employees to spend less time identifying the cause of heating or air-conditioning issues and more time fixing them.

The pilot project builds upon the progress King County has made during the Executive’s administration to make operations more efficient. Over the past five years, King County has reduced its annual energy costs by nearly $3 million.

Seattle-based MacDonald-Miller will install the system for the pilot at no charge to King County. The energy tracking software was developed by ICONICS, Inc. using Microsoft's cloud-based platform.


King County and the City of Seattle are teaming up to improve conditions throughout the watershed surround the Green and Duwamish rivers, stretching 93 miles from the Cascades to Elliott Bay.

The Green/Duwamish Watershed Strategy addresses the need to reduce pollution that occurs upstream, such as stormwater runoff that brings motor oil, pesticides, and other contaminants into the watershed and, ultimately, into the Lower Duwamish, Elliott Bay, and Puget Sound.

Executive Constantine's goal is to coordinate the work already being done by local, state, and federal agencies to manage habitat restoration, salmon recovery, flood control, public health, economic development, and more. This includes clean-up of the 5-mile stretch of the Lower Duwamish that is registered as a Superfund site.

Learn more about the 2014 clean-up plan announced by the Environmental Protection Agency. This plan complements the Executive's effort to coordinate work being done across the 500-square-mile watershed.

King County Executive
Dow Constantine
Dow constantine portrait

Read the Executive's biography