Dear Colleagues,

A disproportionate fraction of growth has been centered around cities with projections that urban populations will increase to 5 billion by 2030, increasing urban land cover by 1.2 million km2 (Seto et al, PNAS, 2012). Urban landscapes present unique environmental opportunities and challenges, including those related to water resources and water quality. Historically, urbanization has lead to increased runoff, decreased infiltration, and decreased water quality, adversely impacting streams (i.e., the urban stream syndrome), rivers, and embayments. Developing countries are often faced with inadequate water and wastewater infrastructure, presenting an additional layer of challenges for water resource and water quality management.

Non-point source pollution is recognized as a fundamental challenge of urban water management. Traditional engineering approaches are increasingly being replaced by distributed, low impact approaches to restore runoff hydrographs, improve water quality, and minimize combined sewer overflows. Although promising, the effectiveness of such approaches with regard to specific contaminants, and on the watershed scale, remains uncertain. It is unclear, for example, whether distributed systems can effectively address nutrient runoff to sensitive receiving water. An evaluation of strengths and weaknesses of LID (and other) remedial systems against specific problems on local and watershed scales is needed.

Dr. Andy James
Guest Editor

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• stormwater
• green infrastructure
• low impact development
• combined sewer overflow
• water reuse
• non-point pollution