Project

Clarifier Launder and Weir Resurfacing

Spalled concrete launder and weir lip rebuilt, reprofiled to a true edge, and lined for an even overflow.

The challenge

What was failing

The concrete launder and weir trough around a clarifier carries the constant wash of water running over the lip and into the trough. Over time that surface spalled and roughened, and the weir lip lost its true line. Once the edge is no longer even, the water no longer spreads evenly across the weir, so the flow channels to the low spots and the wash concentrates there. That uneven flow keeps breaking the surface down, the spalling works back into the trough, and the launder can no longer carry an even overflow the way the clarifier was designed to run.

Smooth lining applied to a wetted concrete containment surface
Our approach

How AAS approaches it

We chip out all the failed and spalled concrete back to a solid base and clean the launder and the weir lip down to sound substrate. Then we rebuild the lost concrete in the launder and along the weir lip with a cold-applied repair mortar, bringing the section back to profile. We reprofile the lip to a true, even edge so the water can spread across it the way it should. Once the substrate is sound and shaped, we line the wetted launder against the water with a coating that leaves a smooth surface, so the trough carries an even overflow and stands up to the constant wash instead of spalling back open.

Assess and map

We survey the launder and weir to map the spalled and roughened areas and check where the lip has lost its true line.

Chip out and clean

We chip out the failed concrete back to a solid base and clean the launder and weir lip down to sound substrate.

Rebuild with repair mortar

We rebuild the lost concrete in the trough and along the lip with a cold-applied repair mortar, returning the section to profile.

Reprofile the weir lip

We reprofile the lip to a true, even edge so the water spreads evenly across the weir.

Line and return to service

We line the wetted launder with a smooth coating against the water and hand the trough back ready to carry an even overflow.

What you get back

The result

Spalled launder and weir lip rebuilt to profile without replacing the structure
Weir lip reprofiled to a true, even edge so the water spreads across it
Wetted launder lined with a smooth surface that carries an even overflow
Trough holds up to the constant wash, finished by factory-trained and factory-certified Belzona applicators
In the field

From the job

Repair and protection work of this kind, performed by AAS crews across Louisiana.

24-hour on-call service

Have equipment that needs to stay in service?

Tell us what is failing. We respond quickly, and we offer 24-hour on-call service.

Call (225) 751-1930