Urban stormwater management in 2050

During the past 40 years, urban stormwater management has evolved from focus on drainage and flood control to inclusion of stormwater quality associated with nonpoint pollution. This paper projects what the urban stormwater field could look like in the year 2050. The projections are based on our best judgments as to the internal and external drivers that are expected to change the field during the next 40 years. Relevant projections by other stormwater groups are reviewed. Anticipated changes include the growing interest in stormwater reuse, on-site control of stormwater using a variety of low impact development alternatives, generation and accretion of recalcitrant residuals, toxics and chemicals as well as changing temporal and spatial phenomena of the urban hydrologic cycle due to changes in climate and patterns of urban settlement. Key expected drivers of changing attitudes are the greatly increasing relative cost of providing water and energy; greater concern about developing more sustainable green materials and infrastructure systems; and technological advances that will allow proactive management of urban stormwater systems using real time control and including source controls.