Cross-passages, invert sumps and low points collect water along the tunnel. Staged sump pumping and treatment lift and clean it from deep within the drive to the surface plant.
Water does not only enter at the face. Cross-passage excavation, invert construction and natural low points all collect ingress along the tunnel, frequently below the level of the portal. Staged sump pumping lifts it to the surface, and because cross-passage and invert work disturbs the ground, that water carries its own slugs of fines and grout. Coordinating the in-tunnel sumps with the surface treatment keeps the whole drive dry and the discharge compliant.
Staged Lift and Treatment
We design the sump and pumping arrangement with the temporary-works team so water is collected at each low point and lifted in stages to the portal plant. The surface treatment is specified to absorb the extra solids slugs from cross-passage and invert excavation. The result is reliable dewatering from deep within the drive, with the treatment train handling the combined load to consent.
Sumps and relay pumps lift water from low points to the surface.
Cross-passages, inverts and low points each drained reliably.
Surface plant absorbs the solids slugs from excavation work.
Coordinated pumping keeps faces and inverts dry to programme.
Water Deep in the Drive
Collecting and lifting water from deep, scattered low points adds pumping and solids-load complexity.
Low points need staged lift to reach the surface plant.
Cross-passage and invert work sends slugs of fines to surface.
In-tunnel sumps and surface treatment must work as one system.
From Low Point to Surface Discharge
Sumps at cross-passages, inverts and low points gather ingress.
Surface buffering flattens the excavation slugs.
Monitored discharge or reuse across the works.
Plant We Build Into This Stage
Coarse and fine screens remove debris and protect pumps and downstream plant.
View EquipmentHydrocyclones strip abrasive excavation sand to protect pumps and media.
View EquipmentHigh-rate inclined-plate settlers cut suspended solids in a compact footprint.
View EquipmentAutomated acid or CO² dosing neutralises high-pH cement-affected water.
View EquipmentMultimedia and pressure filters polish settled water to tight TSS limits.
View EquipmentPre-assembled, road-transportable treatment trains that relocate as work advances.
View EquipmentWhy Choose Reynolds & Bauhm
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