Highland Tank logo

Quality Steel Tanks and Oil Water Separators Since 1946

Applied Process is proud to represent Steel tanks from Highland Tank.

Long considered the standard of the industry, Steel Water Storage Tanks and Oil Water Separators from Highland Tank offer superior strength, durability and craftmanship. Constructed with factory-welded carbon steel, each Highland storage tank is made to order, in both standard and custom sizes, to your application requirements.


Potable Water Aboveground Horizontal white


Potable Water Tanks



Highland highDRO® POTABLE WATER Storage Tanks

* Above and below ground options in 5’4”, 6’, 8’, 10’, 10’6” and 12’ diameter sizes.

* Vertical and horizontal

* Storage capacities from 185 to 70,000 gallons.

* Customizable with a variety of options including manways, stairs & ladders,

cages and catwalks.

* Built to ASME, ASTM, UL, AWWA and OSHA standards as applicable.

* NSF 61 compliant interior liners.

* Standard 24”, 30” and 36” manways

Learn how Highland Tank’s state-of-the-art Oil/Water Separators work.

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Fire Protection Water Storage Tanks



Highland HighDRO® welded steel Fire Protection Tanks are atmospheric tanks specifically designed for fire protection water storage and automatic sprinkler systems. They are constructed, tested and inspected in accordance with NFPA -22 standards.

highDro® Aboveground Vertical Fire Protection Tanks:

  • Wide range of primer and topcoat options including ANSI/AWWA D102.
  • Optional external ladders and platforms and OSHA ladders and safety cages when required.
  • Flat Dished or Coned bottoms.
  • Volumes from 2,000 to 60, 000 gallons


highDro® Aboveground Fire Protection Tanks:

  • Wide range of primer and topcoat options including ANSI/AWWA D102
  • Volumes from 1,500 to 60, 000 gallons
  • UL Saddle supports


highDro® Underground Fire Protection Tanks:

  • HighGuard Corrosion protection complying with UL-1746.
  • Volumes from 2,000 to 60, 000 gallons
  • Three pre-engineered design options – Bottom Drain, Pump Well and Vertical Suction


Wastewater Storage tank

Wastewater Storage Tanks
Single Wall and Double Wall

Highland highDRO® Wastewater Storage Tanks

  • For domestic, commercial industrial or agricultural liquid wastes.
  • Above and below ground tank options.
  • Watertight and leak-free.
  • Liners designed to chemical, corrosion, pH and temperature considerations.
  • Compliant with AWWA, NFPA, UL and API standards as required.
  • Wide variety of manways, fittings and accessories.
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Highland Underground Oil Water Separator

OWS Aboveground Horizontal white

Highland Aboveground Oil Water Separator

Highland Aboveground & Underground OIL WATER SEPARATOR Tanks

Oil Water Separators are designed to separate and remove oil, grease and oil-coated solids from oil water mixtures. Highland OWS tanks all feature patented non-clogging Corella® coalescers to accelerate and heighten the separation process.


Standard Underground cylindrical OWS designs:

  • Widely used in industrial, military and airport applications.
  • Volumes from 350 to 60,000 gallons.
  • Flow rates from 35 to 6,000 gpm
  • Single-wall and double wall options


Standard Aboveground Cylindrical OWS designs:

  • Used when belowground installation isn’t possible or when high flow rates are required.
  • Volumes from 350 to 60,000 gallons.
  • Flow rates from 35 to 6,000 gpm
  • For gravity or pumped influent.


Standard Aboveground Rectangular OWS designs:

  • Widely used in industrial applications for EPA discharge regulation compliance.
  • Volumes from 100 to 30,000 gallons.
  • Flow rates from 5 to 3,000 gpm
  • Single-wall construction