Berkeley Professor of Architecture Nicholas de Monchaux estimates that there are 529 acres of unaccepted streets, just over half the land area of Golden Gate Park. In Local Code [PDF], one of six finalists in UCLA's WPA 2.0 design competition ("Whoever rules the sewers, rules the city"), de Monchaux details his vision for replenishing 1514 of these unaccepted streets by linking contemporary geospatial planning tools with existing public processes through the DPW to implement "a range of local infrastructural gestures, from soil remediation, to victory gardening, to playgrounds and pastures."
Local Code borrows from the work of "anarchitect" Gordon Matta-Clark, who in the early 1970s discovered that New York City auctioned off pieces of unusable land that resulted from surveying anomalies and public-works expansion, so called "gutterspaces," fifteen of which he purchased and developed for Fake Estates, an architectural intervention meant to dissect notions of materiality, property ownership, and prestige.
With Local Code, de Monchaux hopes to accelerate the pace of converting streets into green spaces, particularly in the underserved neighborhoods in the shadows of freeways, where unaccepted streets are abundant. "If you look at the unaccepted streets, it is like heat map of all the areas with health problems, pollution issues, and neglected spaces," he said.