A 14-month pilot and plant scale sludge dewatering study was conducted at the Joint Water Pollution Control Plant (JWPCP). Discharge requirements on the effluent from this facility necessitated that at least 95% of the suspended solids be removed from the primary digested sludge for disposal by alternative means. The applicability of heat, polymers, chemicals and flyash was investigated as a means of conditioning digested sludge for dewatering. Sludge dewatering schemes using horizontal scroll centrifuges, imperforate basket centrifuges, vacuum filters and pressure filter were thoroughly studied. Operational results were obtained from twenty conditioning-dewatering test systems of which five successfully produced the desired suspended solids removal. Full scale cost estimates were prepared for each of the five systems. Estimates were prepared for the requirements and costs associated with the ultimate disposal of dewatered sludges generated from each successful dewatering scheme. It was concluded that a 2-stage centrifuge sludge dewatering scheme (polymer addition to the second stage) with truck hauling of dewatered sludge solids to a landfill was most suitable for the JWPCP. (Modified author abstract)