In 2007, when Arif Khan wanted a garden, friends helped him tear up the asphalt-covered backyard of his home in Portland, Oregon, U.S. Soon afterwards, they won a small grant to depave the front of a local cafe, and in the 15 years since, have completed 75 projects across Portland. Depave’s newest chapter is in Chicago, where more than 60% is covered in impervious surfaces. Architecture professor Mary Pat McGuire and a group of volunteers recently drew up plans to green a public schoolyard in West Englewood that will include pollinator gardens, an outdoor classroom, log structures, bioswales and shady trees. Space to Grow, another Chicago organization, has overhauled 34 schoolyards over the last decade, replacing asphalt with permeable sports fields, rain gardens and other porous surfaces. That has reduced ground temperatures by up to 54 degrees F and alleviated neighborhood flooding by capturing more than 3.5 million gallons of stormwater.