Take an existing 44-acre public housing development in San Francisco’s Visitacion Valley neighborhood. Add a redevelopment program of mixed-income housing, open space and community services. Finally, embed a deep commitment to create a healthier, more sustainable community and you have the Sunnydale Redevelopment in San Francisco’s Visitacion Valley neighborhood. SvR is currently working as Sustainable Infrastructure/Low Impact Development Consultants for this exceptional project that will raise the bar for integrating ecological infrastructure into the urban environment in the San Francisco Bay Area.

Technical Performance

With low infiltration rates, areas of steep slopes and bedrock close to the surface, the Sunnydale Redevelopment site seemed to offer less than ideal geomorphological conditions to implement low impact development. Therefore, our first task was to work with the design team to inform the street geometry and subdivision plating to make sure that we capitalized on the bioretention and infiltration opportunities on site. After studying three stormwater options, the project team is pursuing a strategy that uses the public right of way and building setbacks to manage all of the stormwater on site. In so doing, we can eliminate the need for a large, constructed storage vault while meeting the requirements of the San Francisco Green Building Ordinance.

This strategy mimicked the pre-development, natural flows of the site. Water from the development sites are slowed and given the opportunity to infiltrate on the flatter north-south streets. Then, echoing the flows of a historic stream that ran through the site, a proposed widened right of way along Sunnydale Avenue creates a stormwater amenity: a “stream” that defines and shapes a shared use path in front of several residences.

Design Performance

Throughout the streetscape design, ADA, low impact development and mobility concerns were balanced in a way that will make the streetscapes welcoming for residents. While traditional traffic calming devises such as curb extensions and street trees are used on the bus arterials, several of the minor north-south streets are envisioned as “home zones” where kids can play, while their parents supervise them from the front stoop.

Sunnydale before and after	Sunnydale illustrative birdseye rendering