Vent Shaft System

The FloodBreak® Vent Shaft System is an innovative flood control solution for underground rooms, tunnels and subway stations that have vertical ventilation shafts to the surface.

The system fits securely beneath street-level grates and prevents floodwater from pouring through the vent shaft to the rooms and stations underground. Water can be channelled to existing drainage systems through a weep hole at the bottom of the unit.  This allows water to drain from the system at a controlled rate.   Once the flooding subsides, the vent shaft gates automatically reopen allowing air to flow freely to the space below.

How it works

When the street floods, water flows through the street-level grates and into the vent shaft system. The hydrostatic pressure created by the rising floodwater closes the gates – first the lower gate and then the upper gate – preventing the water from pouring through the vent shaft and into the underground rooms, tunnels or subway stations. When the flood recedes, the system automatically reopens allowing air to flow freely to the space below.

FloodBreak Vent Shaft Systems are custom sized to fit customer shaft openingsOnce installed, The FloodBreak passive flood control system provides permanent flood protection with no disruption to vehicular or pedestrian traffic at the street level. And like all FloodBreak products, they are designed for long service life with minimal maintenance.

The FloodBreak Vent Shaft system is an innovative flood control solution for the NY MTA.


FloodBreak Vent Shaft Systems are custom sized to fit your vent shaft openingThe FloodBreak vent shaft flood protection system sits below street level gratingFloodBreak Vent Shaft System sits below street level gratesNumerous NYC subway lines were prone to street flooding which then poured through vertical vents into subway stations and underground equipment rooms. Rather than extend the vent shafts above the sidewalks, the FloodBreak system allowed the NY MTA to install a flood protection system beneath the street level grating, custom designed to fit into their existing vent shafts.

The vent shaft system includes weep holes at the bottom of the units (seen in yellow at right) that allows water to drain slowly into their existing drainage system without overpowering it and flooding the stations below.

The FloodBreak Vent Shaft system fits securely beneath street level grating allowing unimpeded vehicle and pedestrian traffic.

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