The Active Fluid-Filled Weir is a flexible, water-filled barrier that serves as a dam or cofferdam to isolate work areas for operations such as stream diversion, dewatering, and the repair of docks, boat slips, and pond liners. They are more effective than sandbags and other water-control devices.
The Active Fluid-Filled Weir is a lightweight, portable dam capable of being filled using on-site water sources; it can be deployed wherever there is a need to control, manage, or manipulate water flow. The weir consists of two fundamental components: an inner section comprising two leak-proof polyethylene tubes designed to hold water, and an outer section—referred to as the "master tube"—fabricated from heavy-duty, coated polypropylene geotextile fabric, which serves to contain the two water-filled inner tubes. The combination of the outer tube and the inner tubes constitutes the complete Active Fluid-Filled Weir. The image below shows a cross-sectional view, clearly illustrating the internal and external tube configuration in a typical, fully inflated Active Fluid-Filled Weir.
When the Active Fluid-Filled Weir requires inflation, water is pumped into the two inner tubes. The durable fabric outer tube encases the two water-filled inner tubes, preventing them from rupturing. The interplay of opposing frictional forces and hydrostatic pressures between the inner and outer tubes—acting in alignment with the forces of water accumulation and gravity—generates the necessary pressure to stabilize the weir, enabling it to effectively counteract lateral water pressure. Thanks to the inherent elasticity of the materials used in its construction, the Active Fluid-Filled Weir can conform to most types of surface terrain, providing an exceptional seal that minimizes water seepage.
Active Fluid-Filled Weirs can be manufactured in a variety of sizes, ranging from 0.3 to 5 meters in height (when fully inflated). Standard units are manufactured in lengths of 1.3 or 2.5 meters to facilitate ease of transport. However, units of any length can be assembled and spliced ​​together; shorter, longer, or non-standard lengths can be custom-ordered. By using the accompanying fasteners, two or more Active Fluid-Filled Weirs can be linked to form a continuous dam structure of any required dimensions. The weirs are connected using specialized coupling fasteners (included as standard equipment with every unit). Weirs of different sizes can also be interconnected, allowing for the creation of structures of virtually infinite length. They can be deployed in a straight line, arranged in an arc, or even configured into a complete circular ring. Flexible fluid-filled weirs can also be connected at angles to one another when engineering requirements dictate. Typically, these flexible weirs are coiled into rolls at the factory and subsequently prepared for installation at the construction site. However, large-scale flexible weirs are generally no longer assembled on-site. A standard flexible weir consists of a "main tube" and a pair of internal tubes, wound around a wooden or metal spool. In most instances, this spool plays a crucial role during the installation, retraction, and transportation of the flexible weir.