Belowground Stormwater Management Services

Belowground stormwater management systems play an important role in controlling runoff, capturing pollutants, and protecting commercial properties and surrounding waterways. Often installed beneath parking lots, roadways, landscaped areas, and other developed spaces, these systems manage stormwater without occupying valuable surface space.

Although much of this infrastructure remains out of sight, it still requires regular inspection, maintenance, and occasional repairs to function as designed. Sediment accumulation, clogged filtration media, restricted flow, and deteriorating components can affect system performance long before problems become visible at the surface.

At iSTORMWATER, we provide comprehensive belowground stormwater inspection, maintenance, cleaning, and repair services for commercial properties, HOAs, property management companies, industrial facilities, and other properties throughout Maryland, Washington, DC, Northern Virginia, and Delaware.

From proprietary filtration devices and hydrodynamic separators to underground detention systems and pipe rehabilitation, our certified, experienced crews help property owners maintain their stormwater infrastructure, address deficiencies, and support ongoing regulatory compliance.

Need service for an underground stormwater facility? Contact iSTORMWATER to schedule an inspection or request a maintenance estimate.

Belowground Stormwater Systems We Service

Underground stormwater facilities vary in design, function, and maintenance requirements. Some are engineered to capture sediment and other pollutants, while others temporarily store runoff, promote infiltration, or convey water through the drainage system.

iSTORMWATER services a wide range of belowground stormwater systems, including:

Contech StormFilters

Contech StormFilter systems use replaceable media-filled cartridges to capture pollutants from stormwater runoff. Commonly installed within underground vaults and other engineered structures, these systems require periodic inspection and maintenance as sediment accumulates and filtration media reaches its service capacity.

iSTORMWATER provides StormFilter inspections, sediment removal, vault cleaning, cartridge maintenance, and replacement services to help maintain treatment performance and proper system operation.

Learn More About Contech StormFilters

Jellyfish Filters

Contech Jellyfish Filters use membrane filtration technology to capture fine sediment and other particulate pollutants from stormwater runoff. These systems incorporate specialized filter cartridges and pretreatment components that require appropriate inspection and maintenance procedures.

Our team provides Jellyfish Filter inspections, cleaning, sediment removal, cartridge maintenance, and condition assessments to help commercial property owners protect their stormwater treatment investment.

Learn More About Jellyfish Filters

Hydrodynamic Separators

Hydrodynamic separators (HDS), including oil-grit separators, are underground treatment devices designed to separate sediment, debris, floatables, and certain other pollutants from stormwater runoff.

These systems are frequently used as standalone treatment devices or as pretreatment for downstream stormwater facilities.

iSTORMWATER services a variety of hydrodynamic separation systems, including:

• Aqua-Swirl®
• Contech Stormceptor®
• Hydro International Downstream Defender®
• Contech Vortechs®
• Other manufactured hydrodynamic separation and oil-grit separator systems

Our services include inspections, sediment and floatables removal, vacuum truck cleaning, component assessments, and corrective maintenance based on system-specific requirements.

Learn More About Hydrodynamic Separators

BaySaver Technologies

BaySaver stormwater treatment systems use different separation and filtration technologies to capture pollutants before runoff reaches downstream drainage infrastructure and receiving waters.

iSTORMWATER provides inspection and maintenance services for BaySaver products, including BaySeparator, Barracuda, and BayFilter systems.

From sediment and debris removal to filtration maintenance and component inspections, our team helps property owners address maintenance needs and preserve system functionality.

Learn More About BaySaver Technologies 

Underground Sand Filters

Underground sand filters treat stormwater by directing runoff through engineered sand media that removes suspended solids and certain associated pollutants. Typically housed within concrete vaults or similar subsurface structures, these facilities provide stormwater treatment where available surface space is limited.

Over time, accumulated sediment and debris can restrict flow through the filter media, affecting drainage and treatment performance.

iSTORMWATER provides underground sand filter inspections, sediment removal, pretreatment chamber cleaning, drainage assessments, and maintenance or rehabilitation recommendations based on facility conditions.

Learn More About Underground Sand Filters 

Underground Detention & Infiltration

Underground detention and infiltration facilities manage stormwater volume while maximizing usable space aboveground.

Detention systems temporarily store runoff and release it through a controlled outlet, while infiltration systems are designed to allow captured stormwater to enter surrounding soils where site conditions and system design permit.

Common underground configurations include:

• Corrugated metal pipe (CMP) detention systems
• Concrete stormwater vaults
• Modular chamber systems
• Underground infiltration galleries
• Stone-filled infiltration beds

iSTORMWATER provides inspection, sediment and debris removal, cleaning, structural assessments, and maintenance for underground detention and infiltration facilities. Our team helps identify obstructions, accumulated material, damaged components, and other conditions that may affect system performance.

Learn More About Underground Detention & Infiltration 

Pipelining & Sliplining

Underground stormwater infrastructure also depends on pipes and conveyance systems to move runoff safely through a property. As these components age, they may develop corrosion, separated joints, cracks, deformation, or other structural deficiencies.

iSTORMWATER provides stormwater pipe inspection, repair, and rehabilitation services, including CCTV inspections and applicable pipelining and sliplining solutions.

Depending on pipe conditions, rehabilitation may provide an alternative to full excavation and replacement, helping restore structural integrity and drainage functionality while minimizing disruption to the surrounding property.

Learn More About Pipelining & Sliplining 

Inspection, Maintenance & Repair for Belowground Facilities

Every belowground stormwater facility has unique inspection and maintenance requirements based on its design, components, and operating conditions.

iSTORMWATER provides professional services for underground filtration systems, hydrodynamic separators, detention facilities, infiltration systems, and associated drainage infrastructure.

Our work includes system inspections, vault cleaning, sediment and debris removal, filtration component maintenance, and corrective repairs. We also provide documentation and maintenance recommendations to help property owners manage their belowground stormwater infrastructure.

Learn more about our Stormwater Inspection Services, Preventative Maintenance, and Stormwater Repair Services.

Common Problems Affecting Belowground Stormwater Facilities

Because belowground systems are concealed beneath developed areas, maintenance issues can develop without obvious surface-level warning signs.

Common concerns include:

• Sediment and debris accumulation: Reduces available storage or treatment capacity and may obstruct internal components.
• Clogged filtration systems: Loaded media, accumulated solids, and obstructed flow paths can affect treatment performance.
• Restricted inlets and outlets: Blockages can interfere with drainage, flow control, and normal system operation.
• Structural deterioration: Corrosion, cracks, separated joints, or damaged internal components may require repair.
• Reduced infiltration capacity: Sediment accumulation or clogging can interfere with an infiltration system’s ability to accept stormwater.
• Delayed or inadequate maintenance: Allowing deficiencies to remain unaddressed can lead to more extensive corrective work.

Routine inspections provide an opportunity to identify these conditions and prioritize maintenance before they contribute to larger operational or structural problems.

Why Belowground Facilities Require Ongoing Attention

Unlike aboveground stormwater facilities, many underground systems provide limited visual indications when maintenance issues begin to develop.

Sediment accumulation, blocked internal components, damaged filtration media, and structural deterioration may go unnoticed without an inspection. By the time drainage problems become apparent at the surface, corrective work may be more extensive.

Understanding your system’s configuration, access requirements, and manufacturer-specific maintenance needs is an important part of protecting your investment.

iSTORMWATER helps commercial property owners and managers identify developing issues, prioritize maintenance, and plan for long-term facility care.

Belowground Stormwater Services in Maryland, DC, Northern Virginia & Delaware

iSTORMWATER provides professional belowground stormwater management services for commercial properties, residential communities, industrial facilities, institutional campuses, and other managed sites throughout Maryland, Washington, DC, Northern Virginia, and Delaware.

Whether your property has a single underground filtration device or a network of interconnected stormwater facilities, our team can help identify maintenance needs, address deficiencies, and develop an approach to maintaining your infrastructure.

Schedule Belowground Stormwater Service

Don’t wait until a drainage problem or failed inspection brings attention to your underground stormwater system.

From routine inspections and sediment removal to specialized filtration maintenance and structural repairs, iSTORMWATER provides the services needed to help keep your belowground facilities operating as designed.

Contact iSTORMWATER today at (410) 231-3455 or request service online to discuss your belowground stormwater inspection, maintenance, or repair needs.