8.8 MG (274’ ID x 20’ SWD)
City of Manchester
CDM Smith, Inc., Manchester, NH
Manchester is the largest city in New Hampshire and home to over one-third of the state’s population. Touted as New Hampshire’s “Business Capital,” an ample water supply is essential for Manchester’s growing population and economic development. Manchester Water Works had been experiencing water quality problems with its membrane-covered high-service reservoir. CDM Smith, Inc., Manchester, NH, was hired to design an AWWA D110 Type III prestressed concrete tank to be constructed inside the existing reservoir. Preload was selected as the preferred tank builder for the project.
Built in 1998, this 8.8 MG Preload tank features a reinforced concrete column-supported flat-slab roof, an inside diameter of 274’, and a side water depth of 20’. Preload constructs flat-slab roofs with reinforced concrete, supported by circular columns, each with a footing sized for the allowable soil-bearing capacity. Like all roofs on Preload tanks, this flat-slab roof is designed in accordance with rigorous AWWA standards and ACI code requirements.