A suburban sediment budget: Coarse-grained sediment flux through hillslopes, stormwater systems and streams

Abstract

Sediment in urban stormwater systems creates a significant maintenance burden, while a lack of coarse‐grained bed sediment in streams limits their ecological value and geomorphic resilience. Gravel substrates, for example, provide benthic habitat yet are often scoured from the channel bed only to end up in a detention basin or treatment wetland. This dual problem of both ‘too much’ and ‘too little’ coarse‐grained sediment reflects a watershed sediment budget that is profoundly altered. We developed a conceptual urban coarse‐grained (>0.5 mm) sediment budget across three domains: hillslopes (urban land surfaces), the built stormwater network and stream channels. We then quantified key sources..