NDSStormChamber Systems
NDS StormChamber systems are open-bottom, arch-shaped HDPE infiltration chambers for subsurface stormwater detention, retention, and conveyance. They store runoff below grade — under parking lots, lawns, or landscape — while letting it soak into the soil, so you meet stormwater volume requirements without sacrificing usable surface above.
Store Stormwater Underground, Keep the Surface Usable
As sites add impervious area, codes increasingly require that stormwater be detained or infiltrated on-site rather than dumped to the storm sewer. StormChamber addresses this with modular HDPE arches installed in a gravel bed below grade. Because the chambers are open on the bottom, water both stores inside the void and soaks into the surrounding soil — a true infiltration BMP in permeable soils, and a controlled-release detention vault in tighter soils when paired with an outlet structure.
StormChamber comes in two heights — 18” and 34” — and the chambers stack in layers, so you can add storage depth without expanding the excavation footprint. That makes it a flexible answer for everything from a residential lot that cannot daylight its drains to a light-commercial parking field. It is the larger-scale companion to the point and linear drainage covered elsewhere in the NDS line, collecting flow from catch basins and channel drains before it leaves the site.
Related: NDS Flo-Well Dry Well
For smaller residential jobs, the NDS Flo-Well is a modular ~50-gallon dry well roughly 24” in diameter and ~24” tall (about 28-3/4” with cover). It is gravel-free and holds about 250% more detention than an equivalent gravel pit. With a minimum 8” cover it supports light vehicular loads (~175 psi), can be buried up to 8 feet deep, and stacks up to four units for added capacity — a quick, DIY-friendly way to infiltrate downspout and yard-drain water where a full StormChamber field is more than the project needs.
Specifications
Key specs for NDS StormChamber infiltration systems.
Key Features
StormChamber FAQs
Common questions about NDS StormChamber and Flo-Well systems
A StormChamber is an open-bottom, arch-shaped HDPE chamber installed below grade in a gravel bed. It stores stormwater in the void inside the arch and lets it infiltrate into the surrounding soil, providing subsurface detention, retention, or conveyance while keeping the surface above usable for parking, lawn, or landscape.
NDS StormChambers are available in two heights: 18 inches and 34 inches. The chambers are modular and stackable in layers, so you can add storage depth without enlarging the excavation footprint to hit your required storage volume.
Yes. In permeable soils the open bottom acts as a true infiltration BMP. In tighter, non-permeable soils the system functions as a controlled-release detention vault when paired with an outlet structure that meters the release rate to meet local stormwater requirements.
StormChamber is a larger-scale, modular chamber system for residential-to-commercial detention and infiltration. The NDS Flo-Well is a compact ~50-gallon modular dry well (about 24" diameter and 24" tall) for smaller residential jobs — gravel-free, buriable to 8 feet, stackable up to four units, and rated for light vehicular loads with a minimum 8" cover.
Each NDS Flo-Well holds about 50 gallons and provides roughly 250% more detention than an equivalent volume of gravel because it is gravel-free and hollow. Up to four Flo-Wells can be stacked to increase capacity for higher-flow downspout and yard-drain discharge.
StormChamber is the subsurface storage end of an NDS system. It collects flow from surface points such as catch basins and channel drains and stores or infiltrates it on-site instead of discharging to the storm sewer. Compare it with other detention products on our detention systems page to choose the right volume and configuration.
Related Products & Applications
StormChamber is NDS’s entry in the detention systems product category, and it pairs well with permeable pavers to cut impervious area. Subsurface storage is most often required on sites that add hardscape, such as:
- Parking lots and lots expansion
- Warehouse and distribution sites
- School and university campuses
- Residential lots that cannot daylight drains
Need On-Site Stormwater Storage?
Tell us your site area, soil type, and storage target and our specialists will size a StormChamber or Flo-Well system and provide pricing.