Construction Water Barriers
TrapBag® is a multipurpose construction water barrier you can use in a variety of situations on your job site. Learn how these flood protection solutions can make it easier for your construction crew to work faster and safer in flood-prone areas.
How Contractors Use TrapBag
TrapBag keeps water out of job sites and holds it where the permit says it has to stay, from site perimeters to stormwater ponds.
Flood Protection for Job Sites
A single storm can flood an open excavation and wipe out weeks of work. Crews set TrapBag around the site perimeter before high water arrives, so foundations, equipment, and materials stay dry and the schedule holds.
Stormwater & Sediment Control
Construction runoff carries sediment and pollutants that can’t leave the site. TrapBag can form temporary detention ponds that hold runoff until it settles or is treated, which keeps it out of storm sewers, streams, and water supplies.
Temporary Retaining Walls
TrapBag holds back soil and water along excavations, stockpiles, and cut slopes. Crews fill it with sand or gravel for the life of the job, then dig the fill out when the work is done. With pumped concrete, it becomes a permanent wall.
Where Contractors Use TrapBag
Contractors use TrapBag on jobs where rivers, storms, or runoff threaten the work.
Excavations and foundations
Perimeter barriers keep floodwater out of open pits until the structure is out of the ground.
Bridge and culvert jobs
For in-water work, a temporary cofferdam built from TrapBag cofferdam bags keeps pier, abutment, and culvert work dry.
Roads and utility work
TrapBag protects roadbeds, trenches, and utility corridors near rivers. See how civil engineers specify it on infrastructure projects.
Riverbank and waterfront work
Barriers hold back the river while crews stabilize eroding banks and build along the water.
Fuel and chemical storage areas
TrapBag berms contain spills so fuel and chemicals stay inside the work area.
Sites in floodplains
Barriers go up when a river forecast turns, then come down when the water drops.
How TrapBag Improves on Sandbag Barriers
TrapBag was originally designed as a flood barrier that could withstand hurricane-force storm surges. Contractors later adopted it to keep job sites dry and hold back soil and runoff. Compared to sandbags:
Less labor
Sandbagging a job site can tie up a large crew for days. Two people and a third person operating a skid steer or excavator can fill a TrapBag barrier with sand or washed gravel in a few hours, and that crew can get back to the job.
More durability
A sandbag wall is only as good as its stacking, and a poorly stacked wall is more likely to collapse. TrapBag’s cells are connected and work as one unit, so the barrier holds its shape under water pressure.
Less material
A 100-foot section of 4-ft TrapBag replaces roughly 8,000 sandbags and uses 40% less fill than a stacked sandbag wall of the same size.
Why Choose TrapBags as Flood Prevention Barriers?
Versatility
The same TrapBag system works as a perimeter flood barrier, a stormwater pond, a temporary retaining wall, or a spill berm. Contractors can buy one product and use it for several jobs.
Speed
TrapBag goes up in a fraction of the time a sandbag wall takes. A crew of three with a skid steer or excavator can build a full barrier in hours, using equipment already on site.
Reliability
The U.S. Army Corps of Engineers has tested TrapBag for its ability to protect structures from flood damage. TrapBag also has a 3:1 (mass to hydraulic load) safety factor, which gives contractors margin above the expected water level.
TrapBag Specifications for Construction Projects
Use these figures to scope quantities, draft specifications, and compare bids. Contact TrapBag for spec sheets and submittal documents.
| Specification | Detail |
|---|---|
| Section Length | 50 linear feet per unit; ships folded on pallets and connects end to end |
| Heights | 2 ft and 4 ft; a 2-ft row on a 4-ft row reaches 6 ft; a three-row pyramid reaches 8 ft |
| Sand or gravel fill | Site perimeters, stormwater ponds, and temporary retaining walls; three people with an excavator or skid steer |
| Concrete fill | Permanent walls; pumped into the cells |
| Sandbag equivalent | 100 ft of 4-ft TrapBag replaces about 8,000 sandbags and uses 40% less fill |
| Testing | Tested by the U.S. Army Corps of Engineers |
| Fill sourcing | No special fill; use sand or gravel available near the site |
| Installation | TrapBag Installation Manual (PDF) |
How TrapBags Compare
Earthen Berms
Earthen berms use soil pushed up on site, so they cost little beyond equipment time.
A berm needs gentle side slopes to stay stable, which takes up working room on a tight site. Bare soil also erodes under moving water, and the muddy runoff becomes a sediment problem of its own.
TrapBag has a vertical face and holds its fill inside geotextile fabric, so it takes up less of the site and stays put when water moves against it.
Water-Filled Barriers
Water-filled barriers use water from a hydrant or the site as fill, so there’s no material to haul in, and crews can drain and reuse them.
Job sites are full of rebar, stakes, and equipment that can puncture a water-filled barrier, and one hole can drain a section.
Unlike a water-filled dam, TrapBag cells are self-contained and filled with sand or gravel, so damage to one cell leaves the rest of the wall standing.
Concrete Jersey Barriers
Many contractors already have Jersey barriers on site for traffic control, which makes them a tempting flood wall.
Jersey barriers are made to stop vehicles, not water. Water leaks through the joints between sections unless crews line them, and each section weighs thousands of pounds, so moving them takes a forklift or crane.
TrapBag sections connect end to end into a continuous wall and ship folded on pallets.
Projects
See All Our Past Projects »
Fire Island, New York — Erosion Control
May 28, 2024 Read More » about Fire Island, New York — Erosion Control
Dune Core Stabilization for Hurricane & Storm Surge Protection in Rockaway Beach, New York
May 25, 2014 Read More » about Dune Core Stabilization for Hurricane & Storm Surge Protection in Rockaway Beach, New York
Erosion Control in Sarasota, Florida
May 24, 2018 Read More » about Erosion Control in Sarasota, Florida
Continued Protection After Hurricane Nicole – Volusia County, FL
November 10, 2023 Read More » about Continued Protection After Hurricane Nicole – Volusia County, FL
Chemical Spill Containment – San Juan, Argentina
September 27, 2016 Read More » about Chemical Spill Containment – San Juan, ArgentinaFrequently Asked Questions
A water barrier for construction is a temporary wall that keeps floodwater, river flow, or runoff out of a job site, or holds stormwater inside it. Common types include sandbags, earthen berms, water-filled tubes, and fillable cellular barriers like TrapBag. Contractors choose based on how high the water will rise, how long the barrier has to stay up, and what fill and equipment are already on site.
Contractors control flooding by keeping outside water off the site and managing the water that falls on it. Perimeter barriers and diversion channels hold back rivers and overland flow. Grading, swales, and detention ponds collect stormwater, and pumps remove water that reaches an excavation. Barrier height should match the flood elevation expected while the work is open, with extra height for margin.
In the U.S., most construction sites that disturb one acre or more need coverage under an EPA or state construction stormwater permit, which requires a stormwater pollution prevention plan (SWPPP). The plan spells out how the site will keep sediment and pollutants out of runoff, often with silt fence, inlet protection, and sediment or detention ponds. TrapBag can form those ponds and the berms around them.
TrapBag needs no special fill. Crews use sand or washed gravel for temporary barriers, often from a supplier near the site, and pump concrete into the cells for permanent walls.
A crew of three with a skid steer or excavator can build a full TrapBag barrier in hours. Each 50-ft unit pulls out of its pallet like an accordion, and crews place and fill it in sequence. To remove a sand or gravel barrier, crews dig out the fill and pull out the empty fabric.
TrapBag cofferdam bags have a bottom discharge chute that releases the fill, so crews can empty them, pull them out, and use them again on the next project.
The U.S. Army Corps of Engineers has tested TrapBag as a flood barrier.
What Information Does TrapBag Need for a Quote?
Send the length of the barrier, target height, water source (river, stormwater, or tide), fill material available near the site, project duration, and delivery location. TrapBag will send back a recommended layout, unit count, and pricing.