Phoenix Precast can manufacture a control weir in any shape or length, with or without a base footing. Control weirs are precast concrete structures that are placed across an open channel. The control weir triggers an increased water level, or head, which is measured upstream of the structure. The flow rate over a weir is controlled by having a “V” shaped opening or specially-shaped notch at the top. Phoenix Precast can attach metal plates to the concrete structure to form a sharp-crested weir, if the design requires.