This document is the Nyloplast Weir Structure Sell Sheet. General description, benefits, product information and photographs are included.

The Weir Structure is a Nyloplast PVC or HP Storm Manhole with a panel or plate device secured inside the structure. The weir structures are manufactured to the precise plan design specifications and sent to the job site ready to install. They are designed to divert inflowing water to a preferred outlet, or to regulate the outflow of water from the drainage system.

The weir structure works by regulating stormwater flows into the Nyloplast PVC or HP Storm Manhole structure. The water flow is diverted to a desired outlet from the catch basin, typically to a water quality device, in order to effectively capture pollutants during the “first flush” of a storm event. The Weir Structure may also serve to restrict or regulate the flow of water exiting the drainage system. The restriction is determined by height of the weir and/or the size of the orifice hole in the weir plate and is produced to exact engineered design specifications.

Weir structure benefits include simple and effective method to control water flow into a stormwater management system or water quality device.

Enhanced ability of a water quality device to capture pollutants from storm event. Allows for flexibility to re-direct water flow during a high-flow event. Nyloplast can customize Weir Structures (at the direction of the design engineer) to provide a variety of weir designs for site-specific needs, including “key way slot” and “v-notch” weir designs, and high flow or low flow orifice hole designs to further regulate the flow of stormwater.

General product information clarifies that Weir Structures are available for 24”, 30” and 48” (600, 750 and 1200 mm) diameter drain basins. For use with 4”-36” (100-900 mm) watertight pipe connections. Minimum sumps are required in Weir Structures. Key measure is finish grade to top of weir device in drain basin. Orifice hole diameter/placement based on direction from project engineer.