Regional Climate Partnerships

The City actively collaborates with partners throughout the region to help advance our shared goals. Below are some of the climate-focused partnerships we participate in:

King County Cities Climate Collaboration (K4C)

The City of Mercer Island is a founding member of the King County-Cities Climate Collaboration (K4C), an innovative partnership between King County and over 20 additional partners – including cities and the Port of Seattle - to coordinate and enhance the effectiveness of local climate and sustainability action. 

Mercer Island joined the K4C in 2011 and signed the original K4C Joint Commitments in 2014, and the 2019 refreshed Joint Commitments that same year. K4C partners work together to reduce harmful greenhouse gas emissions by sustainably increasing mobility, investing in renewable energy, promoting clean energy use in buildings and vehicles, and expanding farm and forest protection. 

Eastside Climate Partnership 

The City of Mercer Island is also a founding member of the Eastside Climate Partnership (ECP) formed in 2023 and is made up of the Cities of Bellevue, Issaquah, Kirkland, Mercer Island, Redmond, and Sammamish. The City signed the Interlocal Agreement in 2022. The ECP works collaboratively to create programs that reduce regional sources of climate pollution and advance collective sustainability. Areas of joint programming that Mercer Island participates in include: 

• A regional, coordinated heat pump program through the Energy Smart Eastside program. This program educates residents on the benefits of heat pumps and provides incentives for residential households, affordable housing, and adult family homes. The program plans to expand to additional electric appliance incentives in the future. 
• Preparation of greenhouse gas emissions inventories using standardized methodology for our communities and municipal operations. These inventories support our communities in understanding where progress has been made and provides guidance for where to focus climate action efforts in the future.  
• The Eastside Climate Challenge, which provides an opportunity for community members to track their own actions and engage their neighbors in support of progress towards regional climate goals.