Students for Design Activism

A Proposal for Greenroofs Along the Central Light Rail

Students for Design Activism is working on a proposal to construct small-scale vegetated roofs on the passenger shelters located at the Light Rail Transit stations currently under construction in the Twin Cities.

We believe that the implementation of these greenroofs would be immensely beneficial for the Twin Cities. Not only would the greenroofs provide environmental benefits to the city by capturing stormwater, improving air quality and reducing the urban heat island effect, but they would also help to beautify the LRT stations and enhance the branding of the Central Corridor as a the “Green” line. The visible nature of these improvements would also help competitively place the Twin Cities on the forefront of embracing sustainable urban development.


Greenroofs have been proven to be one of the most beneficial and most easily implemented forms of sustainable infrastructure. They are also commonly recognized in the public sphere as a sustainable practice. By bringing greenroofs down to a pedestrian level and scale, we will have an opportunity to attract and educate the public on the benefits of sustainable infrastructure.

The benefits of greenroofs are many and diverse. From an ecological standpoint, they provide an opportunity to collect stormwater that would normally enter into the city’s stormwater collection system. They also reduce the surface area that absorbs heat, resulting in a decrease in the urban heat island effect. Studies have shown that greenroofs can also mitigate air pollution and help produce a return on investment for their construction when the particle (mono-nitrogen oxide) uptake capacity of plants is valued according to the value of emission reduction credits for cap and trade programs. Greenroofs have been shown to demonstrate many indirect social benefits as well, including job creation, aesthetics and well-being, social cohesion and food security (read more here).

The shelter greenroofs would be a branding effort. Their unique nature will help create a sense of “place” at the light rail stations, which in turn will attract riders to the LRT system.
SDA is researching the feasibility and potential benefits of these greenroofs. In order to propel the project forward, it is necessary to quantify as many aspects of the project as is reasonably possible and conduct a preliminary cost/benefit analysis.

We have already shared these ideas and received feedback and strong support from several organizations, professionals and city employees involved with the Light Rail Transit project, including the Central Corridor Design Center, Saint Paul Riverfront Corporation, City of Saint Paul Gardening Program and the University of Minnesota’s Landscape Architecture Department.

SDA is willing to play whatever role is possible and appropriate in this project, from design planning to project management, and on any scale–be it one experimental rooftop or implementation along the entire Light Rail Transit lines.