Weir (Thomson Weir / V notch sharp crested weir)

Parameter to be measured:

Discharge of open channels

Construction:

1. Planning: Before you can build a weir, you need permissions from different institutions. In my case (Bavaria, Germany) I needed permissions of following people:

• Owner
• Fishing rights
• District office
• Nature conversation agency
• Water right agency

It takes quite a while, around three month, but the adminstration was helpful and I heard that it can take much longer. So start the administration stuff as soon as possible.

1. Accumulation and Drainage of the water: Before you can start the construction of the weir, you have to accumulate the water in front of the construction site and then you have draine the water around or over the weir. If you have electricity you can use pumps (dirt water pumps). Use at least two pumps. One big pump for most of the water and the other for the adjustment, so that the pumps never run dry. In the case you don't have electricity, you can build a small temporary dam and then use a pipe to drain the river water over the weir. I would suggest that you use a 12 V pump to get the water away which is leaking through the dam.

Links

Projects that used the above equipment:

Other related web sites: