Domestic Sewage Flow Criteria for Evaluation of Application of Project Scheme to Actual Combined Sewer Drainage Areas

摘要

The ASCE Combined Sewer Separation Project scheme is concerned with pressurized sanitary sewer systems. Sizing of pressure sewers must be based on attainment of minimum necessary scouring velocities at an acceptable level of frequency, such as for at least one hour each day of the year. Deposition of solids part of the time must be accepted to preclude ultra-conservative design. At the other extreme, peak sewage rates will give rise to maximum hydraulic gradients, and these in turn affect pressure requirements within the system, for booster pumping and/or pressure control. Drainage areas to be examined for hypothetical application of the Project scheme are located in the northeastern portion of the U.S. and in northern California; and this discussion is concerned only with data for those locations. (Author)