Wastewater Clarifier & Concrete Structure Relining

The challenge

A concrete clarifier and the structures around it sit under constant immersion and steady microbial and chemical attack. Over time the surfaces spalled and degraded, and the embedded rebar became exposed and began to corrode. Once rebar corrodes it expands and breaks away more concrete, so the damage spreads and the structure loses watertightness. Left untreated, the clarifier can no longer hold or contain flow as intended.

Our approach

We remove all unsound and degraded concrete back to a solid base and clean the exposed rebar. We treat the steel to repassivate it, then rebuild the lost section with a cold-applied repair mortar that returns the original profile. After the substrate is sound and shaped, we line the surfaces against immersion so the structure stays watertight and protected from ongoing chemical and microbial attack.

1. Assess and isolateWe survey the clarifier and surrounding structures to map spalling, delamination, and the extent of exposed and corroding rebar.
2. Remove and cleanWe break out unsound concrete back to a solid substrate and clean the exposed rebar to a sound condition.
3. Repassivate and rebuildWe treat the steel to repassivate it, then rebuild the lost concrete profile with a cold-applied repair mortar.
4. Line against immersionWe apply a lining over the rebuilt surfaces to make them watertight and resistant to chemical and microbial attack.
5. Return to serviceWe confirm the rebuilt and lined surfaces are sound and ready for the structure to go back into immersion service.