Greening Seattle's Freeway Park: Reducing Pollution's Impact

Freeway Park in Seattle, Washington, is the world's first park built on top of a freeway. The park was constructed in 1976 and was added to the National Register of Historic Places in 2019. As Seattle's freeway is surrounded by densely populated neighbourhoods, Freeway Park may help reduce the pollution exposure of tens of thousands of local residents. A UCLA study found that freeway pollution can cause serious health issues, including higher rates of asthma, heart disease, and strokes. Furthermore, due to historical land use patterns, most residents living closest to Seattle's heavily trafficked roadways are people of colour and those with low incomes, resulting in poorer air quality compared to the rest of the city.

Air pollution

Freeway Park in Seattle was built in 1976 as the first park in the world to be constructed on top of a freeway. The park is bounded by Union in the north and Spring Street in the south, with First Hill to the east and Seattle's financial centre to the west.

The park is located in the downtown area and is designed to be a social space for people from all backgrounds who make up the downtown population. The area around the park is heavely trafficked, and due to historical land use patterns, the majority of residents who live closest to these roadways are people of colour and people with low incomes. As a result, these residents experience poorer air quality compared to the rest of Seattle.

Freeway Park can help reduce air pollution by providing a green space in an otherwise densely populated urban area. The park can act as a barrier between residents and the pollution from the freeway and nearby roadways. Additionally, the park can help absorb some of the pollution that escapes from the freeway.

Furthermore, the city of Seattle has implemented various measures to improve air quality, such as street sweeping to remove pollutants from the roads and the use of Green Stormwater Infrastructure to manage polluted stormwater. The city is also working to reduce pollution in the Puget Sound and the Duwamish River, which have been affected by stormwater runoff and historical industrial pollution.

Overall, Freeway Park in Seattle can help reduce air pollution by providing a green space in a densely populated area, acting as a barrier between residents and pollution, and absorbing some of the escaping pollution. The city of Seattle is also taking additional measures to improve air quality and reduce pollution in the surrounding area.

Water pollution

Freeway Park in Seattle is the first park in the world to be built on top of a freeway. The park was built in 1976 with the aim of providing a space for people from all backgrounds to come together and enjoy the social elements of a city park.

While I could not find specific information on how Freeway Park helps to reduce water pollution, here is some information on Seattle's efforts to improve water quality.

Seattle has excellent drinking water quality, but its major bodies of water—the Puget Sound and the Duwamish River—are polluted by stormwater runoff and historical industrial pollution. Through regional partnerships, the city is working to reduce pollution in these waterways, which is critical for protecting the cultural traditions and economic livelihoods of Seattle residents, especially indigenous communities.

Mitigating Water Pollution

Seattle has implemented several strategies to mitigate water pollution:

• The city has been successful in removing pollutants from roadways through street sweeping. Since 2016, Seattle has removed 475 tons of pollutants from the roads, preventing them from entering local waterways.
• Seattle manages polluted stormwater using Green Stormwater Infrastructure (GSI), an approach that mimics the natural water cycle to slow, clean, and reuse or absorb water.
• The city has constructed bioretention projects in Ballard, Delridge, and Broadview to reduce polluted runoff, collectively managing runoff from over 90 acres.
• Seattle aims to clean up 177 acres of the Duwamish River by 2030 in partnership with King County, the Port of Seattle, and The Boeing Company. As of 2018, the partnership has cleaned 29 acres.
• The city is also working to reduce stormwater pollution by using nature-based methods and expanding GSI partnerships.

Low-Pollution Neighborhoods

Seattle is working towards creating low-pollution neighborhoods to improve air and water quality and community health. The Seattle Department of Transportation (SDOT) and the Office of Sustainability and Environment (OSE) are engaging in community conversations to understand the priorities and visions of different communities for low-pollution neighborhoods.

Emission-Free Areas

Seattle has committed to creating a "major area" that is free from emissions by 2030 as part of the C40 cities Fossil-Fuel-Free Streets Declaration. While there have been challenges and delays, the city is exploring strategies to create areas with low levels of vehicle emissions.

In summary, while I could not find specific information on how Freeway Park directly reduces water pollution, Seattle has implemented various strategies and initiatives to improve water quality and reduce pollution in its waterways. The city is also working towards creating low-pollution neighborhoods and emission-free areas to enhance the health and well-being of its residents.

Stormwater pollution

In the context of Seattle's Freeway Park, the park can play a crucial role in mitigating stormwater pollution by providing a natural barrier that helps to slow down and filter stormwater runoff before it enters nearby water bodies. Here are some ways in which Freeway Park can help reduce stormwater pollution:

• Absorption and Filtration: The park's vegetation, including trees, shrubs, and plants, can absorb and slow down stormwater runoff. The roots of plants and the soil itself act as natural filters, trapping pollutants and preventing them from reaching water bodies. This helps to reduce the amount of pollution entering nearby lakes, rivers, and Puget Sound.
• Stormwater Management Features: The park may incorporate specific stormwater management features such as bioswales, rain gardens, or permeable paving. These features are designed to capture and treat stormwater runoff before it enters the surrounding water bodies. They can remove pollutants, reduce the volume of runoff, and promote infiltration into the ground, reducing the impact on local waterways.
• Reduced Impervious Surfaces: The presence of the park can help reduce the overall amount of impervious surfaces in the area. By replacing concrete or asphalt with greenery, the park contributes to reducing the volume and velocity of stormwater runoff. This allows more water to infiltrate into the ground, replenishing groundwater and reducing the amount of polluted water entering nearby water bodies.
• Educational Opportunities: Freeway Park can serve as an educational tool to raise awareness about stormwater pollution and the importance of environmental protection. Interpretive signage, community events, and educational programs can engage visitors and local residents, encouraging them to adopt sustainable practices that reduce stormwater pollution, such as proper waste disposal and the use of eco-friendly products.
• Habitat Restoration: The park can provide habitat for a variety of plant and animal species, contributing to biodiversity. By creating a healthy ecosystem, the park can support species that are adapted to absorb and process pollutants, further reducing the impact of stormwater pollution on the surrounding environment.
• Community Engagement: The development of Freeway Park can involve the local community in its design and maintenance. By engaging community members, the park can foster a sense of stewardship and encourage residents to take an active role in reducing stormwater pollution. This can include participating in cleanups, reporting illegal dumping, and advocating for sustainable practices in their neighbourhoods.

Overall, Freeway Park has the potential to serve as a natural buffer, mitigating the impacts of stormwater pollution on the surrounding environment. By absorbing and filtering stormwater runoff, reducing impervious surfaces, and raising awareness about environmental issues, the park can play a crucial role in creating a healthier and more sustainable urban environment in Seattle.

Greenhouse gas emissions

Freeway Park in Seattle was built in 1976 and was the first park in the world to be constructed on top of a freeway. The park is bounded by Union in the north, Spring Street in the south, 6th Avenue in the east, and 9th Avenue in the west.

While I could not find specific information on how Freeway Park helps reduce greenhouse gas emissions, Seattle has been taking several measures to reduce its emissions. The city has committed to creating a "major area" that is free from emissions by 2030. Seattle is also working towards implementing three low-pollution neighbourhoods by 2028.

• Vehicle Regulation Cordons: Similar to cities like London, Barcelona, and Seoul, Seattle could implement higher charges for vehicles that emit higher levels of pollution to enter the city core. By 2030, a zero-emissions area (ZEA) will not allow any fossil-fuel vehicles to enter.
• Congestion Pricing: Mayor Durkan has proposed implementing congestion pricing in Downtown Seattle, which involves charging motorists a fee to drive in areas with high traffic congestion. This strategy can help reduce the number of vehicles on the road and encourage the use of public transportation or alternative modes of transportation.
• Improving Public Transportation: Seattle is investing in public transportation infrastructure and increasing the number of zero-emission buses. This will provide residents with cleaner and more sustainable transportation options, reducing the number of private vehicles on the road.
• Green Stormwater Infrastructure (GSI): Seattle is utilising GSI to manage stormwater pollution. GSI mimics the natural water cycle, slowing down and cleaning the water before allowing it to soak back through the soil or reusing it. As of 2018, Seattle manages 260 million gallons of polluted stormwater annually with GSI.
• Street Sweeping: Street sweeping is an effective method to remove pollutants from the air and waterways. Seattle Public Utilities (SPU) and the Seattle Department of Transportation (SDOT) regularly sweep over 90% of the city's arterial streets, collecting around 2,600 tons of trash, leaves, and debris annually.

Noise pollution

Freeway Park in Seattle is the first park in the world to be built on top of a freeway. The park was constructed in 1976, and in 2019 it was listed on the National Register of Historic Places.

The park is located between 6th and 9th Avenues, with Union to its north and Spring Street to its south. To the east is First Hill, and to the west, the park overlooks Seattle's financial center.

The idea for a downtown park over the freeway is as old as the Seattle segment of Interstate 5 itself. The park was built with Forward Thrust bond money, as well as county, state, and federal funding.

Freeway Park provides a space for people from all backgrounds to come together and enjoy the social elements of a city park. However, it is unclear how much the park helps to reduce noise pollution from the freeway. While the park may provide a barrier that reduces noise for people in the park itself, it is unlikely to have a significant impact on noise levels for people living and working in the surrounding area.

To effectively reduce noise pollution from freeways, it may be necessary to consider other solutions such as freeway lids or removing freeway sections entirely. Freeway lids can dampen the dispersal of freeway pollutants, and the trees and greenery added on top can absorb some of the pollution that escapes. Removing freeway sections altogether tackles the problem at its source and can also create room for people to live in the improved neighborhoods using the land recovered from freeway infrastructure.

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