Check/Drop Stuctures
Precon’s Check/Drop Structure is a multi piece (typically using 9-13 pieces) precast concrete structure that assembles together in the shape of an ‘H’ and is installed in an irrigation canal perpendicular to the flow of water. The shape of the structure creates a double water cutoff, ensuring that water cannot get around or under the structure, helping prevent bank erosion.
The Check/Drop Structure is engineered and designed to USBR standards and is a reliable solution for water flow control in a water conveyance system, where there is also a change in elevation. The Check/Drop Structure allows the designer to control water levels and water velocity, which works well in conjunction with Precon’s Inlet/Turnout as a way to obtain necessary water levels for water delivery.
The structure is designed for canal's with flows as large as 3.0 cubic metres per second. We take into account the width of the canal at the top and bottom, the flow of water, and the type of gate when designing the structure. The structure can accommodate Overshot, Stop Log Systems and several other popular gate systems. The Check/Drop Structure can also be used to measure the flow of the water.
Uses
- Flow control in the storage, delivery and drainage of water systems where there is a change in elevation
- Weir structure
- Check structure
- Basic drop structure
Sizes - All dimensions in mm
Q – Maximum Water Flow (in cubic metres per second)
X – Drop (5 = 500 & 10 = 1000)
S – Canal Slope
A – Wingwall Length
B – Sill Length
C – Structure Width (outside)
D – Upstream Wingwall Height
E – Downstream Wingwall Height
F – Upstream Sill Height
G – Downstream Sill Height
- All Check/Drop Structures can accommodate either stoplog guides or overshot gates
- Please note that the floor slab is NOT precast it is cast in place
| Q | X | S | A | B | C | D | E | F | G |
|---|---|---|---|---|---|---|---|---|---|
| 1.0 | 5 | 2.0:1 | 3000 | 2000 | 3500 | 2750 | 2250 | 1600 | 1100 |
| 1.0 | 5 | 2.5:1 | 3500 | 2000 | 3500 | 2750 | 2250 | 1600 | 1100 |
| 1.0 | 5 | 3.0:1 | 4000 | 2000 | 3500 | 2750 | 2250 | 1600 | 1100 |
| 1.0 | 10 | 2.0:1 | 3000 | 2000 | 3500 | 3250 | 2250 | 2100 | 1100 |
| 1.0 | 10 | 2.5:1 | 3500 | 2000 | 3500 | 3250 | 2250 | 2100 | 1100 |
| 1.0 | 10 | 3.0:1 | 4500 | 2000 | 3500 | 3250 | 2250 | 2100 | 1100 |
| 1.5 | 5 | 2.0:1 | 3000 | 2500 | 4000 | 3000 | 2500 | 1750 | 1250 |
| 1.5 | 5 | 2.5:1 | 3500 | 2500 | 4000 | 3000 | 2500 | 1750 | 1250 |
| 1.5 | 5 | 3.0:1 | 4000 | 2500 | 4000 | 3000 | 2500 | 1750 | 1250 |
| 1.5 | 10 | 2.0:1 | 3000 | 2500 | 4000 | 3500 | 2500 | 2250 | 1250 |
| 1.5 | 10 | 2.5:1 | 3500 | 2500 | 4000 | 3500 | 2500 | 2250 | 1250 |
| 1.5 | 10 | 3.0:1 | 4500 | 2500 | 4000 | 3500 | 2500 | 2250 | 1250 |
| 2.0 | 5 | 2.0:1 | 3500 | 2500 | 4000 | 3500 | 3000 | 2000 | 1500 |
| 2.0 | 5 | 2.5:1 | 4500 | 2500 | 4000 | 3500 | 3000 | 2000 | 1500 |
| 2.0 | 5 | 3.0:1 | 5500 | 2500 | 4000 | 3500 | 3000 | 2000 | 1500 |
| 2.0 | 10 | 2.0:1 | 3500 | 2500 | 4000 | 4000 | 3000 | 2500 | 1500 |
| 2.0 | 10 | 2.5:1 | 4500 | 2500 | 4000 | 4000 | 3000 | 2500 | 1500 |
| 2.0 | 10 | 3.0:1 | 5500 | 2500 | 4000 | 4000 | 3000 | 2500 | 1500 |
| 2.5 | 5 | 2.0:1 | 4000 | 3000 | 4500 | 3750 | 3250 | 2050 | 1550 |
| 2.5 | 5 | 2.5:1 | 5000 | 3000 | 4500 | 3750 | 3250 | 2050 | 1550 |
| 2.5 | 5 | 3.0:1 | 6000 | 3000 | 4500 | 3750 | 3250 | 2050 | 1550 |
| 3.0 | 5 | 2.0:1 | 4000 | 3500 | 4500 | 4000 | 3500 | 2200 | 1700 |
| 3.0 | 5 | 2.5:1 | 5000 | 3500 | 4500 | 4000 | 3500 | 2200 | 1700 |
| 3.0 | 5 | 3.0:1 | 6000 | 3500 | 4500 | 4000 | 3500 | 2200 | 1700 |
