Proceedings of the World Environmental and Water Resources Congress 2011: Bearing Knowledge for Sustainability, held in Palm Springs, California, May 22-26, 2011. Sponsored by the Environmental and Water Resources Institute of ASCE. This collection contains more than 500 papers reflecting current research and practice in the world of environmental and water resources engineering, with a special focus on sustainability. For members of the environmental and engineering communities, sustainability has emerged as an important factor in most aspects of their work. Solutions to some of today's most vexing technical, economic, social, environmental, and political issues can be found that integrate sustainability practices. Papers from eight symposia focusing on sustainability are included in this collection: Arid Lands Symposium; Climate Change Symposium; Sustainability Symposium; 6th World Water Forum Symposium: North American Regional Event; 7th Urban Watershed Management Symposium; 8th Groundwater, Hydrology, Quality, and Management Symposium; 13th Water Distribution Systems; and GV Loganathan Memorial Operations Management Symposium. Topics also include communications; education and research; emerging and innovative technologies; environmental; history and heritage; hydraulics and waterways; international; irrigation and drainage; planning and management; water systems security; water, wastewater, and storm water; and watersheds.