A Look at HYDRO International and Its Products

Hydro International Up-Flo Filters underground

A Look at HYDRO International and Its Products

Who is HYDRO International? With over 40 years of industry experience and a global reputation for engineering excellence, HYDRO International is at the forefront of providing advanced products, services, and expertise to help municipalities, commercial enterprises, and industrial customers improve their water management systems. As a trusted name in the field, the company is committed to increasing operational performance while reducing environmental impact. HYDRO International partners with local technology and environmental companies, like Stormwater Compliance Solutions, to provide their customers with turn-key service.

HYDRO International’s Innovative Products for Effective Water Management

As mentioned above, HYDRO International specializes in water treatment products, and some of their more prominent products are listed below. 

Up-Flo Filter: Enhancing Stormwater Treatment

The HYDRO International Up-Flo Filter is an advanced stormwater filtration system designed to capture sediment, heavy metals, oil, and nutrients from stormwater runoff. Combining sedimentation, screening, and filtration, this upflow filter type delivers exceptional surface water pollution removal. Developed in collaboration with the US Environmental Protection Agency (EPA), it has been verified to remove 80 percent of total suspended solids (TSS), with demonstrated removal rates of up to 98 percent. This innovative solution improves water quality and reduces site footprint and maintenance costs.

How Does the Up-Flo Filter Work?

The Up-Flo Filter employs a two-stage treatment process to achieve high removal rates of total suspended solids (TSS) and other targeted pollutants. In the first stage, sedimentation and screening remove very fine particles, trash, and floatables from the stormwater runoff. This initial process ensures that larger contaminants are effectively captured before the water moves to the second stage.


In the second stage, the stormwater passes through a hydroflow filtration system that targets liquid and sediment-bound hydrocarbons, sediment-bound heavy metals, and sediment-bound nutrients. 

Applications of the Up-Flo Filter

What is an upflow filter? Just as the name implies, water must flow up through the filter and out, this allows the system to use gravity and driving head pressure to maximize the physical properties of water flow in the treatment process. The versatility of the Up-Flo Filter makes it suitable for a wide range of applications, and it is a very desirable stormwater filter system. Whether you’re managing stormwater runoff from an industrial site, protecting wetlands or other environmentally sensitive areas, or implementing low-impact development initiatives, this advanced stormwater filtration system can meet your specific needs.


Here are some common applications for the Up-Flo Filter:


  • Industrial sites: This HYDRO International filter is ideally suited to industrial sites that require a high level of treatment to capture solids, nutrients, and metals from runoff.
  • Redevelopment or new construction: When it comes to source control for redevelopment or new construction projects, this filter provides an effective solution for treating stormwater runoff and urban stormwater management.
  • Water quality volume detention systems: The Up-Flo Filter can be integrated into water quality volume detention systems to ensure effective stormwater treatment before it is discharged.
  • Industrial or multi-sector general permits: Sites operating under industrial or multi-sector general permits can benefit from the advanced stormwater treatment provided by this filter from HYDRO International.
  • Sustainable drainage projects: The Up-Flo Filter is an excellent choice for low-impact development (LID), sustainable drainage (SuDS), LEED, and water-sensitive urban design (WSUD) projects.

Benefits of the Up-Flo Filter

The Up-Flo Filter offers a range of benefits that make it a superior choice for stormwater treatment:

Exceptional Treatment for Any Catchment

The modular filtration components of the filter allow you to customize your design to meet the specific needs of any catchment area. This advanced system can deliver the desired treatment if you need to capture high levels of trash, silt, sediment, oils, metals, or nutrients.

Two-Stage Treatment in a Single Unit

This product achieves two-stage treatment in a single device. The system combines pretreatment, screening, and filtration, ensuring highly efficient stormwater treatment without requiring multiple units or processes.

Space-Saving Design

The Up-Flo Filter’s higher loading rates result in a smaller treatment footprint. This space-saving design saves construction time and money and makes installation easier.

Low-maintenance Solution

This filter is designed for long-term maintenance with minimal disruption. The risk of treatment disruption or breakage is significantly reduced with no moving parts. Additionally, the longer media life of the Up-Flo Filter allows for extended periods between servicing. The easily removable and replaceable media bags simplify maintenance, while the media cartridge modules stay in place.

Downstream Defender: Reliable Stormwater Treatment

Another groundbreaking product offered by HYDRO International is the Downstream Defender, an advanced hydrodynamic separator for stormwater. This compact and low-maintenance stormwater treatment best management practice (BMP) captures and retains surface water runoff sediments, oils, trash, and floatables. The Downstream Defender enables engineers to deliver effective pollutant removal at a single point in the drainage system, making it an ideal choice for industrial stormwater pollution control and areas where high solids and trash capture are a must.

Benefits of the Downstream Defender

Just like the Up-Flo Filter, the Downstream Defender has many benefits, too. Below is a partial list and how the Defender works.

Space and Cost Savings

One of the significant advantages of hydrodynamic separation is the ability to treat high peak flows while occupying a smaller footprint compared to other structural BMP systems. This compact design translates to easier installation, reduced expenses, and less labor-intensive work. Furthermore, this stormwater treatment system is proven to prevent washout of captured pollutants. Carefully engineered internal components effectively isolate pollution storage areas, ensuring that captured materials are retained even during high flows.


The Downstream Defender offers adaptability to suit site-specific requirements. It can accommodate changes in outlet pipe direction, providing engineers with flexibility in design options.

Low Headloss

With low headloss, the stormwater vortex separator enables site flexibility, making it suitable for shallower areas. This feature allows engineers to optimize system design for various site conditions.


How Does the Downstream Defender Work?

The Downstream Defender stormwater treatment system employs several mechanisms to enhance vortex separation, ensuring efficient pollutant removal and preventing washout of stored materials. Let’s take a closer look at its operation:


  • Introduction of contaminated stormwater: The stormwater enters the Downstream Defender tangentially from the vessel’s side, generating a rotating flow that spirals around the outside of the dip plate.
  • Capture of oils, trash, and floatable debris: As the flow continues to spiral, oils, trash, and floatable debris rise to the water surface and are trapped in the oil and floatables storage volume.
  • Sediment capture: The low energy vortex motion directs sediment inward along the benching skirt and into the protected sediment storage zone as the flow slows down around the dip plate cylinder.
  • Flow redirection: The benching skirt and center cone redirect the rotating flow up and inward between the center shaft and dip plate cylinder, away from the stored sediment.
  • Effluent discharge: The outlet pipe discharges treated effluent from within the dip plate cylinder, ensuring the longest possible residence time for effective treatment.


HYDRO International not only provides innovative products but also offers a range of comprehensive services to design, install, operate, and maintain effective water management systems. Their expertise extends to municipal, commercial, and industrial sectors, ensuring customers receive tailored solutions to meet their needs. By leveraging their vast experience and engineering excellence, HYDRO International helps clients manage flooding, improve water treatment, and reduce water pollution. Reach out to HYDRO International directly or call one of their supporting maintenance companies to get more information. 

Contact our Team at [email protected] today to speak with a specialist about your service needs.  Visit our website at SCSstorm.com.

Daniel Flynn has been with Stormwater Compliance Solutions for over 10 years working on a wide range of engineering and construction projects in the stormwater field. He is responsible for business development, engineering analysis and design, project scheduling and management. He has extensive experience in hydrology and hydraulic of small watersheds and this experience has allowed him to expand the company’s stormwater management services to a wide array of clients. He has a bachelor of science in Forest Engineering from the State University of New York, College of Environmental, Science and Forestry. He is a licensed Professional Engineer in the State of New Jersey and a Certified Erosion Sediment and Stormwater Inspector (CESSWI).