Green spaces for conservation within urban areas are limited. Many municipalities have storm-water facilities that may be used for conservation purposes. The Village of Bradley, Illinois, USA, requires new storm-water facilities be planted with native vegetation. We assessed the quality of several of these facilities using diversity metrics. Sites planted with diverse seed mixes had diversity at a level similar to larger, high-quality restorations in the region. Using a landscape approach to maximizing biodiversity can increase municipal-wide diversity beyond that found at individual sites.