How to Install a Weir Box
While Weir Boxes eliminate many of the typical installation considerations of Weir Plates, some considerations have to be taken into account when installing a Weir Box.
Installing the Weir BOX
The Weir Box must be mounted so that the weir plate is level from front-to-back and from side-to-side.
The mounting surface of the weir box should be sufficiently consolidated that it will not shift or move out of position due to settlement, frost heave, etc.
The weir crest must be horizontally level.
- If present, the bevel of the weir crest must be set downstream.
In earthen channel applications, the channel downstream of the Weir Box should be reinforced / armored so that scour does not occur. Scouring can lead to the Weir Box shifting out of position.
- Water Measurement with Flumes and Weirs (ISBN 90-70754-55-X) provides details of channel reinforcement, however as a rule of thumb protection should extend at least 4 Hmax downstream (and not less than 5-feet [1.5 m].
