Life as a Design Element of Hardened Urban Shorelines

Abstract Armored urban shorelines have historically impoverished life on the waterfront. Materials and forms were chosen to discourage the settlement of marine communities and human access. This has weakened shoreline habitats and adjacent terrestrial and aquatic ecosystems and diminished urban human experiences by reducing links to nature. Augmentation of existing structures and new waterfront designs for specific ecological goals such as salmon habitat improvement are reversing these trends. With the integration of advances in ecology, social science, engineering, architecture, and regulation, urban shorelines can be designed and built to enrich human experience and natural resources through connections rather than through separation and can then be considered “living shorelines.” Such a holistic approach should extend from the subtidal to the terrestrial vegetated and built environment. As with traditional soft sediment living shorelines, life can be included from the outset and be applied as an integral design element providing many functions as well as ecosystem services and social well-being benefits. We present challenges and recommend solutions for broad incorporation of this new vision for urban shorelines. We need data on biological recruitment processes, a better understanding of human social engagement with the urban shore, and continued development of materials for strength, customizability, ecosystem compatibility, and reduced carbon footprint. Measuring and tracing impacts or contributions will be difficult. Improved assessments of investment risk and reward for urban areas are needed to fund these efforts, and regulatory adaptability is needed to allow the transformation of urban shores into living shores.