In this book, Ahmadu Bello University (ABU) sanitary sewerage system was appraised. Using a developed evaluation criteria and scoring format, the system performance was evaluated and found to be 50%, hence necessitating that an improvement design be carried out. The improvement design consisting of an optimized sewer extension network was put forward. The dynamic programming - optimization techniques as employed by SEWER 3.0 software, has been utilized to identify and determine the best pipe-slopes and sizes combinations for the proposed sewer extension network. The output of the SEWER 3.0 analysis reveals that an additional pipe length of 3,298 m is required for the proposed network at an optimized total cost of $161,097 USD). In order to make proper evaluation of the existing WSP, the ponds were visited, and influent and effluent qualities of the ponds were determined and compared with standard effluent quality requirements. The results obtained for the suspended solids and faecal coliform quality parameters show that WSP treatment performance is generally low on the average. This led to a higher than normal total sludge to be generated.