› Constant upstream water level is maintained
› 100% use of the available in-system storage volume
› Reduced construction costs because retention
basins can be downsized
› retro-fitting into existing basin overflows possible
› Stainless steel construction ensures reliable trouble
› Virtually maintenance free
The Overflow Bending Weir Type O is designed to maintain maximum water storage levels upstream of the weir thus allowing full usage of all the available upstream storage volume, while not adversely affecting the overflow weir capacity.
Once a combined sewer overflow tank (or sewer) or a stormwater overflow tank (or sewer) is full, any additional influent water must be able to reach the receiving stream. The traditional way of accomplishing this was by using fixed weirs. However, fixed weirs have inherent disadvantages including: increased water pollution, lower usable tank and sewer storage volumes and no backflow protection. To avoid these disadvantages, increasing use is made of bending weirs such as the uniquely designed Overflow Bending Weir Type O.
The Overflow Bending Weir Type O is designed to open just enough to allow the additional influent water to overflow the weir while maintaining the maximum allowable upstream storage water level. This ensures that the frequency of overflow events is diminished which results in reducing the discharge of highly polluted water to the receiving stream.
The Overflow Bending Weir Type O, is designed to react instantly and will automatically adjust itself in order to constantly maintain the designed overflow water level. The key component of the Overflow Bending Weir Type O is the eccentric control disc. This eccentric control disc is designed to supply a permanent balance of forces between the hydrodynamic pressure of the water (acting on the upstream face of the bending weir) and the counterbalancing weight. Should the additional inflow be greater than the design peak discharge, the Overflow Bending Weir Type O will remain fully open and act as an emergency overflow.
The Overflow Bending Weir Type O may be installed in either new or existing overflow structures in order to increase storage capacity. While the Overflow Bending Weir Type O is custom made, it is shipped ready to install. It is simply dropped in place and anchored to the existing concrete structure. The Hydraulic capacity of the Overflow Bending Weir Type O is at least equal to that of a standard overflow weir. This means that the upstream water level is not adversely affected by the presence of the Overflow Bending Weir Type O.