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The Kraken Filter - Stormwater Treatment

The Kraken Filter - Stormwater Treatment

The Kraken® Filter is a state-of-the-art stormwater treatment system utilizing advanced membrane filtration, ensuring a high level of removals for total suspended solids (TSS), phosphorus, nutrients, metals, trash, and hydrocarbons.

Select Kraken Filter Approvals

The Kraken Filter has been evaluated by some of the most stringent stormwater technology evaluation organizations in North America, including:

  • TAPE_FcWashington State Department of Ecology (TAPE) GULD – Basic, Phosphorus 
  • New Jersey Department of Environmental Protection (NJDEP) Certification
  • New Jersey Corporation for Advanced Technology (NJCAT) Verification
  • Virginia Department of Environmental Quality (VA DEQ)
  • Canadian ISO 14034 Environmental Management – Environmental Technology Verified (ETV)

Kraken Filter Configurations

  • Vault
  • Curb Inlet
  • Grate Combo Inlet
  • Catch Basin
  • Kraken High Capacity (for areas requiring NJDEP approval)

Kraken Filter Maintenance

  • Lowest lifecycle cost of any media filter with fast and simple maintenance procedures.
  • Easily cleaned with a standard vacuum truck, and reusable filter can be cleaned with a standard garden hose.
  • Contech has a network of Certified Maintenance Providers to provide maintenance on the Kraken Filter and other stormwater BMP’s.

Kraken Filter Features and Benefits


High surface area membrane filtration

Superior pollutant removal in a small footprint

Built-in pretreatment chamber

Easier maintenance and extended filter life

Self-draining filters

Extended filter life

Optional internal bypass

Eliminates the need for a separate bypass structure

Lightweight, rinsable, reusable filters

Fast, easy maintenance

Kraken® Filter - A Stormwater Filtration Solution


The Kraken® Filter is a state-of-the-art system utilizing advanced membrane filtration, ensuring a high-level of removal for not only TSS, but also metals, trash, nutrients, and hydrocarbons.

At the heart of the Kraken are the filter inserts. A 30.75” tall filter has over 170 sq ft of surface area, allowing it to treat 8 gpm at a loading rate of only 0.05 gpm/sf.

Available in vault and manhole configurations, the Kraken filter inserts are lightweight, and reusable, providing maximum performance and minimum maintenance.

How the Kraken® Filter  Works


  • To reduce loading on the membrane filter, runoff is initially passed through the pretreatment chamber to capture trash, hydrocarbons, and sediments.Once runoff is pretreated, it is directed to the filter chamber for primary treatment.
  • During the fill-up process, an integrated interior riser tube prevents flow through the membrane filter until the water level nears the top of the filter. This ensures loading is evenly distributed over the vertical height, maximizing efficiency.
  • Membrane filtration begins when the water level reaches the top of the membrane filters. Treated water then passes down the riser tube, collects in the underdrain manifold and flows to the discharge chamber.
  • An optional internal bypass is available with most system configurations. When flows exceed the treatment capacity of the system, the water level rises and goes into bypass. High flows are conveyed from the pretreatment chamber directly to the discharge chamber to prevent scouring of fine sediments captured within the filtration chamber.

Kraken Filter Performance Testing Results

Pollutant of Concern Units Median Effluent Concentration Median Removal Efficiency

Total Suspended Solids (TSS)

mg/L 4.2


Total Phosphorus (TP)

mg/L 0.026


Total Nitrogen (TN)

mg/L 1.28


Moter Oil

mg/L 0.77


Diesel Range Organics

mg/L .32


Total Copper (TCu)

µm/L 15.3


Total Zinc (TZn) µm/L 49.9 62%


Source: WA DOE TAPE Testing:



Technical information for this product is centrally located in the technical guides section.

View Technical Information

The Contech Advantage

Agency/Regulatory Guidance

Our team is ready to provide you with expert advice and assistance on local regulatory requirements, resulting in faster approvals.

Solution Development

Our engineers can review your requirements, weigh all options, and recommend the optimal solution to integrate with your site designs.

Technical Expertise

Our engineers can assist by providing product specific engineering calculations such as hydraulics, buoyancy, foundation reactions, and unit sizing.

Cost Estimates

We can quickly provide engineer’s cost
estimates to assist with your solution
selection process.

Site Specific Drawings

Our engineers can provide site-specific drawings for proposals, project meetings, and submittals, helping you be more efficient with your time.

On-site Assistance

Contractors know time is money, so we provide preconstruction meetings, delivery coordination, and on-site installation support to ensure a timely, smooth installation.

High Volume Applications

Designing, manufacturing and installing high-volume stormwater detention and treatment systems requires expert engineering, planning, and logistical support to manage costs and keep the project on schedule and under budget. When you need a proven, large scale stormwater management system, “Go Big” with Contech.

Filtration for Removing Pollutants Prior to Discharge

Media filtration systems - like our StormFilter, Jellyfish Filter, and Kraken Filter are able to remove the most challenging pollutants from stormwater, including total phosphorus, soluble metals, oil, and very fine particles. Available in a variety of configurations (vault, manhole, catch basin, high flow and volume), these systems can be engineered to treat a wide range of flows within your drainage system and capture pollutants prior to discharge off-site.

Filtration Systems for Water Quality

The Stormwater Management StormFilter, Jellyfish Filter, and the Kraken Filter provide the highest level of treatment and meet the most stringent regulatory requirements. These low maintenance systems combine pretreatment and filtration, and are able to target site-specific pollutants to meet your water quality goals. Our field-proven products have earned hundreds of standalone BMP approvals from regulatory agencies nationwide.

Filtration for LID Designs

The Stormwater Management StormFilter, Jellyfish Filter, and the Kraken Filter can be easily configured as decentralized, small scale inlets, including catch basin, curb inlet and manhole systems to meet LID treatment requirements. The systems provide high removal efficiency for primary pollutants of concern.