Water Quality Treatment (Initial – Retired saved for info)

Water Quality Treatment (Initial – Retired saved for info) 2017-04-04T17:26:40+00:00

Hydrodynamic Separation

(Suspended Solids, Sediment, Gross Solids, Debris, Grease and Oil)

Jensen Deflective Separator (JDS)

A Full Capture, Screening, Swirl-Concentrating Stormwater Treatment Unit

The Jensen Deflective Separator (JDS) is a non-blocking, screening, swirl-concentrating, stormwater treatment system with no moving parts to maintain. JDS units are available in precast manholes as inline or offline units as well as smaller drop-inlet/catch-basin solutions. Capable of treating flows from 0.7 to 72 cubic feet per second, the JDS retains captured pollutants, even with bypass flows in excess of the treatment design rate.

Using the proven continuous deflective treatment process, the JDS captures 100% of trash and debris particles equal to or greater than the screen apertures of either 2400 or 4700-micron (μm).  The treatment process also develops vortex separation, which enables fines to settle through a larger range of flow rates than could be settled in a classic settling tank of the same size.  All JDS units are equipped with an oil baffle, and oil sorbents can be added for enhanced efficiency to permanently remove 80% to 90% of free oil and grease.  The JDS system has a small-footprint, deployed underground in either manholes and/or vaults, which enables greater land-use options than larger, land based water quality treatment systems.  The systems are maintained with straight-forward vacuum clean-out efforts from the surface, consistent with standard practices, using readily available vacuum trucks.  Combined, these features make the JDS a cost-effective solution for stormwater treatment in small or large watersheds.

Jensen Vertical Flow Clarifier (VFC)

Jensen Vertical Flow Clarifier Installation

The patented Vertical Flow Clarifier (VFC) from Jensen Stormwater Systems is a flexible and efficient stormwater treatment device for designers and engineers looking for a cost effective method to remove trash, fine sediments, petroleum hydrocarbons and neutrally buoyant debris from stormwater. The VFC is effective in a variety of applications as a single treatment unit or as part of a treatment train.

Stormwater runoff is piped into a VFC sized for anticipated storm events and pollutants of concern. The VFC allows for any inlet-outlet pipe geometry, both horizontally and vertically, to meet unique site and hydraulic constraints. The inlet pipe is connected to a center vertical stand pipe that surrounds a full depth well-screen basket. This screen basket is the first treatment process, removing trash and coarse debris. Flow continues through the full-depth screen to an annular space between the screen and stand pipe. Outlet ports near the bottom of the stand pipe initiate upward vertical flow where very fine sediments settle to the bottom. Detention in the clarifier allows floatable pollutants to rise to the surface. Near the surface, a partially submerged baffle retains floatable contaminants, including petroleum hydrocarbons, which  are retained by an absorbent boom material. Stormwater then flows under a continuous baffle and over a concentric v-notch weir which catches neutrally buoyant debris.

The concept of the VFC is based on performance perfected in water and wastewater treatment plants throughout the world. This design was modified by Jensen Precast for designers and engineers who must deal with highly variable stormwater hydraulics/flow rates, complex site constraints and highly variable pollutants.


(Suspended Solids, Sediment, Gross Solids, Debris, Grease and Oil)

What are your stormwater Pollutants of Concern?

Jensen Stormwater Systems offers efficient filtration solutions for removing very fine solid pollutants as well as the more complex pollutants of concern from stormwater runoff using a variety of inert and ionic exchange capacity filter media.  Designed within precast concrete structures, our diverse and flexible filtering and media options can be deployed in a variety of configurations, including manholes; vaults; gulleys, gutters, and trenches; and drop inlets, curb inlets, and catch basins.

Jensen provides filtration systems that treat stormwater for simple as well as more difficult to treat pollutants:

    • Total Suspended Solids (TSS) as well as the other fine and coarse sediments
    • Heavy metals
    • Nutrients
    • Hydrocarbons
    • Pesticides
    • Oxygen-demanding substances (biologic and chemical)
    • Oil, grease, and polyaromatic hydrocarbons (PAH)
    • Bacteria

Cartridge Filtration

Cartridge Filter 60-degree

Jensen Stormwater’s filtration systems incorporate tested and proven 3P Hydrosystem cartridge filters, which provide swirl-concentrating, sedimentation pre-treatment followed by advanced, up-flow filtration in one unit.  Designed for diverse applications, these systems are typically deployed as multi-cartridge systems in precast manhole or vaults structures.  For smaller developments, the filtration systems are deployed in trench vaults, precast drop and curb inlets, or catch basins.

Our cartridge filtration systems provide both physical and chemical treatment for removing Total Suspended Solids (TSS), metals (Al, Cd, Cr, Cu, Fe, Ni, Pb, Zn), nutrients (phosphorous & nitrogen), and hydrocarbons (grease, oil, etc.). The advanced filtration cartridges use fire-hardened, expanded ceramic spheres engineered to have a very large specific surface area. The media substrate is specially coated with oxides to produce a large cation-exchange capacity (CEC) to target the removal of heavy metals and nutrients.  The result is a filtering media well-suited for severe stormwater treatment applications.

Filter media is fine-tuned to address specific pollutants of concern by blending in Granular Activated Carbon (GAC), perlite, zeolite or peat fiber for enhanced bio-filtering.  The media is also equal to, or superior to, granulated activated carbon for addressing the removal of pesticides.

Trench Filtration Systems

Precast Trench Filter System

Jensen Stormwater Systems provides an option to treat sheet stormwater flow, such as parking lot runoff, in a grated linear trench.  Trench filter configurations are ideal for installations having shallow drainage piping and sites with poor drainage or very little available slope or driving head.

The trench filter system starts with a precast trench with a heavy duty grate, which resist heavy traffic and aircraft loadings.  Stormwater enters through the top grate into a pretreatment box to remove debris, gross solids and coarse sediment.  The pretreatment box fills, and water passes through a centered plastic screening grate, spilling onto a filter pad. Stormwater gravity-flows through the engineered media in the filter pad, which lies below the pretreatment box and atop an ᴧ-shaped plate with perforations along the edge.  Filtered, treated water exits the perforations and drains down the channel invert.

Bacteria and Pollutant Filtration Systems

Helix Bacterial Filter in Precast Vault

Jensen Stormwater offers filtration solutions for reducing bacteria in stormwater while also removing debris, sediment, and hydrocarbons.  Our precast manholes and vaults are engineered to deploy the StormSafe™ and Helix ™ filtering systems, each of which utilizes a proven anti-microbial media from Fabco Industries. The bacteria and pathogen killing capacity of these filters is derived from a chemically bound, non-leaching, antimicrobial agent that lasts the lifetime of the media. This antimicrobial filtration is non-toxic, having zero toxicity impact to the receiving water’s biota.

A wide range of design options provides an ability to remove bacteria and pollutants of concern from water quality treatment flows ranging from a few gallons per minute up to 9 Cubic Feet per Second (CFS). High treatment flows are typically addressed with the Helix filter in a horizontal-flow, vault configuration. Weir configurations ensure that the design water quality flow is completely driven through the microbe-killing foam media. The weir also serves as an overflow bypass system for flows greater than the water quality design flow.  Moderate to low volume treatment systems are engineered into manholes, curb inlets, and drop inlets beneath the trash grate using either cartridge or Helix filters.


(Suspended Solids, Sediment, Debris, Grease and Oil)

  • StormVault® (SV)
  • Jensen Precast High Velocity Interceptor (JPHV)
  • Sand/Oil Separators

Total Petroleum Hydrocarbon Removal

(Advanced Oil/Water and Sand/Oil Separation)

  • Jensen Coalescing Media Separator (JCMS)
  • Jensen Coalescing Plate Separator (JCPS)
  • Oil/Water Separator (API design)
Questions? Contact Us

For any of the following:

  • Design Assistance
  • Details and Drawings
  • Information about Products, Applications, and Services
Stormwater Resources

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Jensen Water Resources

Jensen Water Resources is comprised of three specialized teams: Jensen Pump Stations, Jensen Stormwater Systems, and Jensen Advanced Onsite Wastewater Systems.

The Jensen Pump Stations team provides high-quality pump stations for municipal, commercial, industrial, and residential applications. The Jensen Stormwater Solutions team provides products and systems for a diversity of stormwater best management practice applications.
Jensen Advanced Onsite Wastewater Systems creates advanced treatment systems for removing pollutants from wastewater.