The Community Design Collaborative started Infil Philadelphia to promote workable, innovative design solutions to revitalizing older urban neighborhoods. Infil Philadelphia: Soak It Up! focuses on green stormwater infrastructure and will showcase selected projects from Sept. 17 to Oct. 19 at Philadelphia’s Center for Architecture. It also is hosting a national green infrastructure design competition, with a focus on retrofits. Registration is open from Oct. 4 through Nov. 30, and submissions are due Jan. 15.