Wastewater Tanks

Tanks for Wastewater Treatment

Vessels required in wastewater treatment plants include equalization tanks, sludge digesters, effluent storage tanks, clarifiers, aeration tanks, SBR tanks, and package treatment tanks. Each of these tanks provide an ideal application for the Prestressed Concrete design, which permits economical construction and freedom from the usual corrosion problems encountered in wastewater treatment facilities. Installations depicted here are representative of superior structures built by Crom.

Aeration Tanks

  • Can be partially or fully buried.
  • Built to close tolerance on the diameter.
  • A circular beam may be built on top of the tank to accommodate rotating equipment.


CROM has built nearly 300 clarifier tanks – experience has taught us to pay close attention to the following: floor slope, sumps, pipe penetrations, equipment anchorages and bridge supports.

Interior and exterior launders are built as an integral part of the tank.

Aerobic and Anaerobic Digesters

  • Prestressing wires can be spaced to accommodate multiple wall penetrations.
  • Can be built with a free-span prestressed concrete dome.
  • Built to accommodate fixed or floating steel covers, aluminum domes or membrane covers.

Elongated Prestressed Concrete Tanks

  • CROM has built more than 35 tanks ranging in capacity from 820,000 to 14,100,000 gallons
  • Single and multiple trains available
  • Include a steel shell diaphragm, shotcrete walls, linear and circumferential prestressing

Modified Egg-Shaped Style Digesters

  • We provide a unique concrete hopper-forming system, which requires no thru-wall form ties.
  • Prestressed concrete wall placed on top of the hopper is available poly-lined or with shotcrete interior.
  • Optional free-span concrete dome or conical concrete roof both designed to support rooftop equipment.

Sequencing Batch Reactors (SBRs)

Crom works closely with the equipment suppliers to locate and embed mooring cable anchors and shotcrete bosses for airlines and mooring arms. Accommodations for the influent manifold, decanter manifold and waste sludge manifold are also provided. A platform or circular exterior walkway integral with the wall is a common add on.

Package Treatment Tanks

In the mid-1990s, CROM developed a design which included an exterior prestressed concrete tank with steel channels embedded in the tank floor to accommodate steel partitions by others. The combination of the superior CROM wall with steel partition walls proved to be the most long-term, economic product design for package treatment plants.

Reclaimed Water Storage

These tanks are often found at wastewater facilities, but because of their attractive appearance and the ease of adding architectural embellishments, CROM tanks can be located in highly visible areas, such as golf courses, where the reuse water is used for irrigation.

Flow Equalization Tanks

CROM flow equalization tanks are an ideal solution for addressing peak flow conditions. The attractive appearance of CROM tanks makes them suitable for construction anywhere in the collection system.

Contact Us