Stream Restoration in Urban Environments: Concept, Design Principles, and Case Studies of Stream Daylighting

Abstract

This chapter explores the viability of urban stream daylighting as a stream restoration and green infrastructure technology. The history and impacts of “traditional” methods of managing urban streams by placing them in underground pipes are presented and then challenged by proposing daylighting as an alternative urban stormwater management technique. We explore methods of site selection, stream analysis, and natural stream channel design along with construction considerations in urban environments. We review four case studies in the USA demonstrating the most common daylighted stream channel types, which address some of the specific issues and outcomes of current urban stream daylighting efforts. Compared with case study research in 2006–2007, the majority of daylighting projects are now being utilized to manage stormwater volume in an effort to prevent flooding in downtown business and residential districts. Improvements to water quality and habitat corridors are also important, but are secondary to urban flood control. Our conclusions indicate that urban stream daylighting projects are on the rise across the country, in both urban and rural city centers, but that costs and technical complexity are also on the rise due to heavy urban site constraints and limited available land for establishing more naturalized stream channels.