New York City (the City) is designing a 290 mgd water treatment plant (WTP) that reduces operation complexity and plant footprint. The design includes an off-site combined solids processing strategy at the Hunts Point wastewater treatment plant (Hunts Point). This strategy involves solids conveyance from the Croton WTP through a seven mile force main to Hunts Point. Hunts Point dewaters indigenous and visitor digested sludge and is capable of dewatering additional solids loads. In a significant improvement over the conventional strategy, the proposed design introduces the water treatment solids at the point of wastewater treatment solids processing, thereby minimally increasing the contribution of water treatment solids to the activated sludge unit. To evaluate the potential effects of combined solids processing on dewatering operations at Hunts Point, a comprehensive experimental study has been formulated with the following objectives: determine advantages and disadvantages of blending solids versus separate solids handling; determine the impact of blending solids on solids-liquids separation and dewaterability; determine optimal centrifuge operating conditions for maximal solids-liquids separation and dewaterability; determine optimal polymer dose for maximal solids-liquids separation and dewaterability; determine compliance of cake solids with US Environmental Protection Agency CFR 503 standards for land application; and, determine the impact of the centrate emanating from combined solids processing on nitrification kinetics. Preliminary bench-scale centrifugation studies have indicated a higher degree of solids-liquids separation (lower supernatant solids concentration) but lower dewaterability for samples containing a higher proportion of water treatment solids. Includes tables.