Oil Water Separators

Coalescing Plate and Media Pack Separators

Oil Water Separators offer improved performance over traditional interceptors and sedimentation tanks. Jensen Precast coalescing plate separators and media packs specifically target the removal of oil, grease, or total petroleum hydrocarbons (TPH) for stormwater or wastewater applications. Accelerated sedimentation is also promoted inside the separator. Jensen Precast oil water separators are engineered with performance, maintenance, and durability in mind. Our coalescing products are housed in Jensen Precast manufactured concrete for the most structurally sound, corrosion-resistant, and watertight installations. As a result, our oil water separators offer increased flexibility to meet any coalescing plate and media pack separator project needs.


How It Works

  1. Stormwater or wastewater containing oil, grease, or other total petroleum hydrocarbons (TPH) enters the underground precast concrete coalescing separator through the inlet pipe.
  2. As fluid enters the first chamber, preliminary sedimentation and oil removal occur.
  3. Fluid passes through coalescing media packs or plate separators that remove oil, grease, and TPH from the source fluid. Accelerated sedimentation is also promoted inside the separator.
  4. Accumulated pollutants are prevented from escaping during subsequent or high-intensity storm events by sorbent mats, specialized plumbing configurations, and baffles.
  5. Treated effluent is allowed to exit the coalescing separator.
  6. Periodic maintenance is required to remove the accumulated pollutants, clean the coalescing units, and replace sorbent mats.

Oil Water Separators function based on Stokes Law. Coalescing devices shorten the distance an oil particle must rise or sediment must fall thereby speeding up the removal process. Coalescing devices come in different configurations. We offer two designs: Media-Pack Separators and Plate Separators.

Our media pack separators are made with an oleophilic (oil attracting) material and create laminar flow ideal for separation of oil and sediment.

Our plate separators operate based on the lamella principle and incorporate design guidelines developed by the US Army Corps of Engineers.


Water Quality

  • Standalone treatment unit
  • Pre-treatment unit
  • Component of a treatment train

Project Types

  • Car Washes
  • Wash Racks
  • Vehicle Maintenance Facilities
  • Commercial & Industrial Sites
  • Industrial General Permit Compliance
  • Fuel Stations
  • Parking Lots
  • Federal & Local Government Facilities



  • Receive typical and site specific plan and profile drawings for all Jensen Stormwater System Units with engineer’s value estimates.
  • Leverage our readily available tools to support storage and runoff calculations, size our systems, and satisfy stormwater management goals.


  • Create competitive bids with quantified, specific information and pricing.
  • Get installation weights and guidance to support estimation of your installation effort.
  • No hidden installation requirements or costs.


  • Complete your projects on time with well constructable plans inherent into all Jensen Precast products for installations that are quick and easy.
  • Secure, safe delivery and timely setting of your stormwater management systems with our expert drivers and delivery personnel.
  • Gain peace of mind with our easy to maintain systems that require minimal upkeep and safe access post install.