Key Sustainability Milestones

In 2006, thanks to a grassroots effort of citizens, the City of Mercer Island added the following to the Vision Statement in the City's Comprehensive Plan:
Mercer Island strives to be a sustainable community: Meeting the needs of the present while preserving the ability of future generations to meet their own needs. We consider the relationship between the decisions we make as a community and their long-term impacts before committing to them. We understand that our strength is dependent on an open decision-making process that takes into account the economic, environmental and social well-being of our community.”
 
On May 7, 2007, the City Council unanimously adopted Resolution 1389 which committed the City to calculate its first annual carbon footprint and to strive for GHG emissions of 80% below 2007 levels by 2050, in alignment with King County targets, for both the community as a whole and City operations. Note: In comparison, the Washington State requirement for State agencies at the time was 50% below 1990 levels, by 2050; see RCW 70.235.050; this has since been strengthened. Learn more about the City's GHG Data and emissions tracking.
 
In 2007, Mercer Island joined hundreds of cities worldwide in becoming a member of ICLEI, Local Governments for Sustainability. Among the benefits was access to GHG tracking software, which allowed the City for the first time to quantify its total municipal and community-wide emissions, and track the effectiveness of reduction programs. Selected indicators of emissions status from this software began to be included in the City's annual performance measures Report Card.

In 2008, the City began developing sporadic work plans to identify annual sustainability actions and programs; see example below.  Also launched at this time was a Resource Conservation Manager (RCM) program with Puget Sound Energy, which jointly funded a part-time staff position to seek out and reduce energy-wasting practices and equipment, across all City operations and facilities.

In 2011, Mercer Island joined King County and other local cities as a founding member a new, nationally-recognized, coordinated effort to jointly tackle climate issues and enhance the reach of each City's sustainability initiatives: the King County-Cities Climate Collaboration (K4C).

In April 2012, the City began purchasing renewable energy credits through PSE's Green Power Program, equivalent to 35% of the electricity used by municipal operations. The City also kicked off a challenge campaign to sign up an additional 125 homes and businesses for Green Power.

In 2012, the City convened a group of citizens, experts, and Council members, known as the Sustainability Policy Task force, to develop recommendations to keep the City moving forward. The final report included near-term, achievable actions, as well as longer-term aspirational goals; in 2013 the City hired its first part-time Sustainability Manager to help enact these recommendations.

In September 2013, the City won national recognition from the EPA as Green Power Community of the Year for its very successful Green Power sign-up campaign (enrolling an additional 250 homes and businesses), and its commitment to local solar energy generation, such as the demonstration array at the Community Center. The City reports its green power achievements to the EPA every year.

In April 2014, on Earth Day, the City launched its plastic bag ban, prohibiting single-use, disposable plastic bags for most situations, with regulations modeled on other WA communities. Learn more.

By the end of 2014, the City's first Solarize rooftop solar installation campaign had added 50 new arrays on homes and businesses around the Island, tripling generating capacity.

In October 2015, the City and Mayor Bassett were profiled in CityVision, the journal of the Association of Washington Cities, for climate and sustainability work.

In June 2016, the City added code that all new construction in Town Center must meet LEED Gold or Built Green 4-Star standard, as well as other measures, such as pedestrian-friendly design.​ (See MI Code, Section 19.11.050)

In 2016, the City along with King County and other partners in the King County-Cities Climate Collaboration, was recognized with a national Climate Leadership Award from the EPA. 

In 2017, the City increased its renewable energy credit purchase to 100% of municipal usage, and also announced its intent to meet (by 2020) all of its electricity needs for government operations by directly funding a new wind farm in Western Washington, through a 20-year purchase agreement with Puget Sound Energy, along with other major partners.

In January 2018, The City of Mercer Island received SolSmart Gold designation from the Department of Energy for meeting stringent and objective criteria targeting removal of obstacles to solar development and indicating that it is “open for solar business.”  Gold status in particular recognizes the City's solar installation achievements, which total 116 (and over 900 kilowatts of generation) at the time of writing.

At its January 2018 Planning Session, the City Council determined that the City should further deepen its ongoing commitment to sustainability within all municipal operations and across the entire community by making it one of the 2018-2019 Council Goals.

In February 2018, the Council voted to use the STAR Community Rating System as a means to evaluate progress towards Island-wide sustainability, including not just traditional natural systems and climate/energy issues, but also broader topics such as equity, empowerment, and public health and safety. The STAR system consists of a set of 49 standardized objectives, with a menu-based voluntary certification track. STAR has since been absorbed by the US Green Building Council's LEED for Cities program.

In July 2018, a 3-month pilot bikeshare project with LimeBike was launched using 25 electric-assist rental bikes available 24/7, Island-wide, intended to improve Island mobility.

In October 2018, the City wrapped up a 6-month exploratory rideshare program with providers Lyft and Uber which provided highly-discounted rides between the main Park & Ride and any other Island location. Hundreds of residents and commuters tried rideshare for their first/last-mile connections to regional bus transit, and also received cheaper rates for shared vs solo rides.

By December 31, 2018, the community had added another 61 rooftop solar installations in just 12 months, thanks to a second round of the popular Solarize program, which provided tech support and a group discount. In the last four years, the City has grown from 33 installations to 184, now capable of producing 1.5 Megawatts of solar power. The City even has a demonstration array of its own, installed in 2013 at the Community Center.

In early 2019, the City continued its program of improving bicycle route signage around Town Center, the I-90 Trail and along the Mercer Ways (the "Mercer Island Loop").

By 2019, the City had increased its public EV chargers to a total of 4 dual 240-volt units at City Hall and the Community Center

In November 2019, the City Council unanimously endorsed an updated version of the City's pledge (Read Resolution 1570) to continue local and regional work on greenhouse gas (GHG) reduction measures as part of its membership in the King County-Cities Climate Collaboration (K4C).  Foremost among the shared goals is continuation of work towards reducing GHG emissions 50% by 2030 (compared to 2007 levels). Learn more about the City's GHG Data and emissions tracking.

In December 2019, the City Council adopted language in its annual Comprehensive Plan update that inserted policies around greenhouse gas reduction and climate impact mitigation by the City.

In late 2020, the City announced that all of its government operations were now powered by clean, renewable energy from a new wind farm in Western Washington, lowering its carbon footprint by 38%. A twenty-year contract to purchase carbon-free wind power directly from Puget Sound Energy replaced the City’s prior electricity mix, over half of which was still based on coal and natural gas. Learn more about Green Direct wind.

In early 2021, the City Council approved funding to expand the City's half-time Sustainability Manager role into a full-time position.

In November 2021, Mercer Island signed on to the national US Climate Mayors initiative, joining almost 500 other cities that are working collectively on reducing GHG emissions. 

By the end of 2021, Electric Vehicle (EV) and Plug-In Hybrid Vehicle (PHEV) registrations in Mercer Island had increased from just 27 to almost 1300 in only 10 years. View other sustainability tracking metrics.

In January 2022, the City officially launched the development of its first-ever Climate Action Plan.

On Earth Day 2022 (April 22), the City launched the Mercer Island Climate Challenge, an online carbon footprinting platform that makes it easy and fun to reduce and track your environmental impact by picking the actions that fit your goals and lifestyle.

In July 2022, the City began an electric heat pump promotion and installation program in partnership with four other Eastside cities (Bellevue, Issaquah, Kirkland, and Redmond) and multiple affordable housing organizations. Learn more about the Energy Smart Eastside campaign.

On April 4, 2023, the City Council unanimously adopted the City's first Climate Action Plan identifying a range of measures to achieve GHG reductions and improved resiliency. Learn more and how to get involved.