IWA has adopted the Hydraulic Design and Management of Wastewater Transport Systems and made these guidelines available as an IWA publication. The CAPWAT Guidelines were developed in a Dutch Joint Industry Project on CAPacity losses in WasteWATer mains, a research project for the dutch wastewater industry that started in 2003. Together with engineering companies, suppliers and pipeline owners, and in close cooperation with Delft University, Deltares researched the behaviour of capacity reducing gas pockets in wastewater pressure mains. 


You can order a copy (soft-cover or ebook) from the IWA website: http://www.iwapublishing.com/books/9781780407821/hydraulic-design-and-management-wastewater-transport-systems