Great Neck Water Pollution Control District WWTP - Final Clarifier Tank

Water and Wastewater Facilities

D&B has some 50 years experience in the wastewater engineering industry, encompassing virtually all facets of wastewater design. Our structural engineers have designed:

  • Primary and secondary clarifiers.
  • Sludge storage tanks.
  • Thickening tanks.
  • Digester tanks.
  • Grit removal
  • Pump station wet wells.
  • Valve chambers.
  • Primary and final settling tanks.
  • Aeration tanks.

Material Selection for Structures Below Grade

Tanks, clarifiers, valves, channels, chambers and wells are often constructed as below grade structures, subject to high hydrostatic forces, soil pressures and a multitude of corrosive liquids and conditions. Material selection is critical and D&B engineers carefully choose between typical steel reinforcement and epoxy-coated reinforcement for concrete structures, stainless steel or hot-dipped galvanized steel depending on atmospheric conditions and various concrete mix designs, and actual installation methods are meticulously considered when designing a concrete structure.

Foundation Design

Foundation design for new structures or the expansion of existing structures is a key element of the structural design process for wastewater engineering. Structures such as tanks, chambers and wells must be designed for various loading conditions. Worst-case loading scenarios must be carefully considered and analyzed prior to selecting foundation type and design.

D&B’s structural engineering team has experience with shallow and deep foundations, ranging from spread footings and strip footings for lightly loaded structures, to timber or steel piles, helical piles and concrete caissons for more massive structures or structures placed in poor soil conditions.

A clear understanding of a structure’s utilization, the existing soil conditions and all potential load combinations is critical for the safe and efficient design of wastewater structures. D&B’s structural engineering team has provided structurally sound, cost-effective foundation designs for the wastewater industry throughout the Metropolitan New York City area.


Federal, state and local governments often have to choose between providing new infrastructure elements or rehabilitating existing structures. D&B’s structural engineering team has vast experience in the restoration of existing structures to meet structural codes and in the repair of deteriorating structures with the goal of returning to originally intended full operational capacity. Our structural engineering team assesses existing conditions to determine proper repair, restoration or retrofitting techniques necessary to add years of service life to concrete, steel and/or masonry wastewater structures. D&B’s structural engineers also have experience in modifying structures to meet current FEMA flood elevations based on Base Flood Elevation requirements developed as a result of Superstorm Sandy’s severe impacts on the metropolitan area.

Water and Wastewater Facilities Contact:

Shaun T. McGrath, P.E., CCM
(516) 364-9890, ext. 3420

Joseph H. Marturano
(516) 364-9890, ext. 3308

Water and Wastewater Facilities Project Profiles:

Great Neck Water Pollution Control District, Wastewater Treatment Plant Expansion