ASCE/EWRI 45-05 provides guidelines for the design of urban stormwater systems, covering topics such as site analysis, system configuration, hydrology, hydraulic design, nonstructural considerations, structural design, and materials. ""ASCE/EWRI 46-05"" presents guidelines for the installation of urban stormwater systems and discusses subjects such as contract documents, preconstruction site inspection, construction, and inspection. ""ASCE/EWRI 47-05"" provides guidelines for the operation and maintenance of urban stormwater systems, topics include: operation and maintenance plans, water quality, periodic inspection, and maintenance. The Standards in this volume were developed by the Urban Drainage Standards Committee, which is responsible to the Environmental and Water Resources Institute (EWRI) of ASCE. These standards are intended to compliment design procedures of the ASCE Manuals and Reports on Engineering Practice No. 77, Design and Construction of Urban Stormwater Management Systems.