A Workflow and Inventory Analysis of Green Infrastructure in Redwood City, CA

The Public Works Department of Redwood City (Public Works) designs, builds, and maintains public infrastructure for its nearly 86,000 community members residing on the western shores of the San Francisco Bay. In compliance with federal, state, and local regulations governing the treatment of stormwater runoff, Public Works plays an instrumental role in ensuring that harsh pollutants are diverted from watersheds, protecting sensitive ecosystems. Traditionally, stormwater runoff has been routed through the City’s “gray” infrastructure — a well-established network of cement and steel designed to extract pollutants before the runoff reaches the San Francisco Bay.1 In recent decades, however, new stormwater management practices have emerged as more sustainable and potentially cost-effective alternatives to traditional “gray” infrastructure.2 These practices are reflected in new systems involving green infrastructure (GI), which mimics natural filtration processes and helps treat water by removing pollutants before reentering local waterways. Some examples of GI include “green” roofs, bioretention areas, porous pavements, and rain gardens.3 Increasingly, Redwood City has relied more heavily on GI as part of its stormwater management system, and in the coming years, City staff anticipate a significant expansion of GI inventory. Staff in Public Works, however, have reported a series of logistical problems relating to the implementation, monitoring, and maintenance of GI within their jurisdiction. First, City staff informed us that, relative to “gray” infrastructure facilities, monitoring of their GI facilities has been complicated because Public Works lacks a single, reconciled inventory list of all the GI facilities within Redwood City. Specifically, it is our understanding that multiple City staff rely on at least three different inventory lists to inspect, track, and maintain GI, which creates coordination challenges across City departments and divisions. Second, City staff generally alluded to the lack of an efficient management and tracking system for GI. In particular, because GI maintenance responsibilities vary with GI ownership (e.g. public, private, private in public right-of-way), staff noted the challenges of ambiguous maintenance responsibilities, which can fall to multiple City departments and divisions. Finally, Public Works staff expressed the desire to understand how other cities approach the aforementioned issues related to tracking and maintaining GI.