We’ve got all the right pieces.
But even the most flexible stormwater products won’t arrange themselves. To succeed in this rapidly changing environment, you need a partner to help you navigate the complexities of local regulations – someone who is responsive to your requests, saves your customers money and accelerates the design process. That’s why Contech is the trusted partner you can count on for stormwater management solutions.
Our local contacts are experts who are ready to help!
Stormwater management is becoming increasingly complex as regulations become more strict with each permit cycle. It’s no longer enough to simply move water away from a site—we are now often required to retain and treat it. Traditional methods and BMPs simply aren’t enough to address these evolving challenges effectively.
To succeed in this rapidly changing environment, you need a partner to help you navigate the complexities of local, state and federal regulations — one who is responsive to your requests and provides innovative solutions that save your clients money and accelerate the design process.
In addition to stormwater expertise, Contech offers a wide range of innovative, flexible product solutions engineered to solve your site’s unique challenges and reduce long-term maintenance costs. From traditional BMPs to LID solutions, our ongoing investment in robust laboratory and field evaluations ensures we have a variety of solutions to comply with local regulations so your projects get approved the first time. With our responsive team of stormwater experts, local regulatory expertise and flexible stormwater management solutions, Contech is the trusted partner you can count on for all your stormwater management needs.
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Stormwater Filtration Solutions
Contech routinely provides engineers with design drawings, sizing documentation, operation and maintenance guidance, and performance verification documentation for inclusion in stormwater management plans. Because local plan check requirements vary, please contact your local Contech Stormwater Consultant to develop a submittal package tailored to your project’s specific needs.
No, Contech does not currently offer a plastic crate detention system. Contech has chosen not to manufacture this type of system due to concerns about long-term access, inspection, and maintenance.
Underground detention systems collect sediment, trash, and debris over time, so the ability to inspect and clean the system is an important design consideration. Many plastic crate systems have limited internal access, which can make it difficult to verify system conditions, remove accumulated material, or perform maintenance throughout the life of the project.
Instead, Contech focuses on underground detention solutions that provide accessible storage, including corrugated metal pipe, steel-reinforced polyethylene pipe, ChamberMaxx plastic chamber systems and UrbanPond precast concrete detention systems. These systems can be designed with manholes, risers, cleanouts, and other access points to support long-term inspection and maintenance.
Contech stormwater treatment systems can be configured upstream or downstream of a variety of detention systems, including above-ground ponds and underground detention systems.
The detention systems may be concrete, metal or plastic, depending on site needs. Contech manufactures detention systems in each material type to accommodate a variety of site conditions. The final configuration should be reviewed by the project engineer to confirm proper sizing, hydraulic grade line, bypass requirements, access, maintenance approach, and local agency approval.
Municipal stormwater flow rates and pollutant concentrations are highly variable over the course of a storm, between storms, seasonally, and with changing activity in the contributing watershed. Because of this variability, no stormwater control measure (SCM) is going to perform exactly the same on a given site, nor can anyone guarantee a particular SCM will always achieve a specific level of pollutant removal will be achieved on a given site. However, Contech conducts extensive testing on our products to establish their capabilities over a range of representative influent conditions.
Contech systems certified through the Washington State Department of Ecology TAPE program have been evaluated using field data from at least 15 qualifying storm events. This helps capture the natural variability expected at real-world sites. TAPE certification indicates that the system has demonstrated the ability to meet the applicable performance goals under the program’s testing criteria, provided the system is properly designed, installed, operated, and maintained. Unusual influent conditions, atypical pollutant characteristics, extreme loading, or inadequate maintenance can affect performance and should be considered when setting expectations.
Systems certified by the New Jersey Department of Environmental Protection have been independently verified to provide specific sediment removal performance at approved flow rates under laboratory testing conditions. NJDEP testing uses silica particles with a controlled particle size distribution as a surrogate for typical stormwater solids. In actual field applications, the particle size distribution, density, organic content, and composition of stormwater solids can vary significantly over time. So, while NJDEP certification provides a valuable benchmark for comparing the relative sediment removal capabilities of stormwater control measures, it should not be interpreted as a guarantee of identical performance under all field conditions.
The best BMP for a shallow site depends on the available rim-to-invert depth, pipe sizes, hydraulic grade line, treatment requirements, and whether the BMP is at-grade or underground.
For shallow sites, compact systems such as Vortechs, Filterra, the Modular Wetland Linear, Jellyfish Filter, StormFilter, or certain inlet-based treatment systems may be considered depending on the pollutant removal goal and local agency acceptance. In general, shallow sites require early coordination because the controlling factor is often not just the BMP height, but the combination of inlet pipe elevation, outlet pipe elevation, bypass routing, maintenance access, and hydraulic head loss. Your local Contech Stormwater Consultant can help evaluate available depth and recommend feasible BMP options for the project.
Most Contech products can be installed using standard civil construction equipment such as excavators, loaders, compaction equipment, and, where required, cranes or other lifting equipment. The exact equipment depends on the product type, structure size, site access, and contractor means and methods. Contech provides project-specific drawings and installation guidance, can participate in pre-installation meetings, and can have personnel on-site to help contractors understand proper layout, lifting, placement, bedding, backfill, and access requirements during installation.
Stormwater treatment systems are designed to manage runoff and remove pollutants before water enters storm drains, groundwater, rivers, lakes, or other receiving waters. The right system depends on the project’s drainage area, pollutant targets, regulatory requirements, available footprint, hydraulic conditions, maintenance expectations, and site constraints.
Common types of stormwater treatment and management systems include:
Hydrodynamic separators
Hydrodynamic separators use swirl, screening, settling, or flow-control processes to remove sediment, trash, debris, and floatables from stormwater runoff. They are often used as pretreatment upstream of detention, infiltration, filtration, or other BMPs.
Filtration systems
Filtration systems pass stormwater through engineered media, cartridges, or filter structures to remove sediment, nutrients, metals, hydrocarbons, and other pollutants. These systems are often used where a compact footprint or higher level of pollutant removal is needed.
Biofiltration and bioretention systems
Biofiltration and bioretention systems use soil, media, plants, and microbial activity to slow, filter, and treat runoff. Depending on the design, treated water may infiltrate into the ground or discharge through an underdrain. These systems are commonly used for Low Impact Development, Green Infrastructure, and Environmental Site Design projects.
Detention systems
Detention systems temporarily store stormwater runoff and release it at a controlled rate to help reduce peak flows and protect downstream drainage infrastructure. While detention systems are primarily used for water quantity control, they are often paired with pretreatment or treatment BMPs to help remove sediment, trash, debris, and other pollutants before runoff enters the storage system.
Infiltration systems
Infiltration systems temporarily store runoff and allow it to soak into the surrounding soil. They can help reduce runoff volume, recharge groundwater, and lower downstream flow rates, but they require suitable soils, groundwater separation, and pretreatment to protect long-term performance.
Treatment trains
In many cases, stormwater treatment is most effective when multiple BMPs are used together. For example, a hydrodynamic separator may provide pretreatment before a detention, infiltration, filtration, or bioretention system. This approach can improve pollutant removal, simplify maintenance, preserve storage capacity, and help protect downstream systems.
Contech can help engineers evaluate stormwater treatment and management options based on site conditions, regulatory requirements, pollutant removal goals, available space, hydraulic design, maintenance access, and long-term performance needs.
Phosphorus and metals are typically removed from stormwater through a combination of physical, chemical, and biological treatment processes. The right approach depends on the pollutant targets, site conditions, runoff characteristics, regulatory requirements, available footprint, and maintenance expectations.
For phosphorus, treatment often focuses on removing both particulate-bound phosphorus and dissolved phosphorus. Particulate phosphorus can be reduced by capturing sediment and suspended solids through settling, screening, filtration, or hydrodynamic separation. Dissolved phosphorus usually requires additional treatment through engineered media, adsorption, chemical binding, or biological uptake.
For metals, treatment often includes removing fine sediment particles that metals attach to, as well as using filtration or media-based systems that can capture dissolved metals. Biofiltration and bioretention systems can also help reduce metals through filtration, adsorption to soil or media, plant uptake, and microbial activity.
In many cases, a treatment train is the most effective approach. For example, a hydrodynamic separator may be used as pretreatment to capture trash, debris, and larger sediment before runoff flows to a filtration, biofiltration, or bioretention system. This helps improve pollutant removal, protect downstream BMPs, and simplify long-term maintenance.
Contech can help engineers evaluate stormwater treatment options for phosphorus and metals based on site-specific requirements, approved treatment technologies, hydraulic conditions, maintenance access, and long-term performance goals.
