Specialised water treatment solutions for tunnelling projects and metro systems. TBM slurry treatment, bentonite recovery, groundwater dewatering, and construction site runoff management with Global Standards Reference standards.
Groundwater treatment for tunnel dewatering operations. Remove suspended solids, adjust pH and manage contaminated water.
Recycle tunnelling wastewater for TBM slurry makeup, dust suppression and concrete batching.
Sediment and suspended solids removal for tunnel construction wastewater.
Complete water treatment for tunnel boring machines and construction dewatering.
Underground construction presents unique water treatment challenges that demand specialised solutions. Tunnel Boring Machines (TBMs) generate massive volumes of slurry containing excavated spoil and bentonite. Groundwater ingress requires continuous dewatering with treatment before discharge. Construction runoff carries sediment, oils, and chemicals that must be managed to meet environmental regulations. Reynolds & Bauhm systems are engineered to handle these demanding conditions while ensuring compliance with international standards including ISO, CE, and regional environmental regulations.
Comprehensive water treatment solutions designed specifically for underground construction environments with rapid deployment and mobile capabilities.
High-capacity separation systems for tunnel boring machine slurry with solids removal, bentonite recovery, and water recycling.
Explore Metro TbmTreatment of groundwater ingress during excavation with sediment removal, pH correction, and compliant discharge.
Explore Metro GroundwaterSediment and contaminant removal from surface water runoff during construction activities with temporary treatment systems.
Explore Metro DewateringTreatment of wastewater from vertical shafts and metro stations including cleaning, drainage, and operational water.
Explore Metro ShaftsEffective separation of oil and grease from wastewater generated by tunnelling equipment and machinery washdown.
Explore Oil Water SeparationPortable treatment systems that can be deployed quickly and relocated as projects progress with plug-and-play operation.
Explore Metro EquipmentFrom cutter-face support pressure to the polishing pond — the physics that govern tunnelling water
Slurry-shield TBMs circulate a bentonite suspension to support the excavation face, transport spoil to the separation plant, and protect downstream tools. Slurry density, viscosity and yield point are tuned to ground conditions; the separation plant removes the freshly cut spoil while preserving the bentonite for recirculation.
| Stream | Density / TSS | pH | Key Solids | Notes |
|---|---|---|---|---|
| Fresh make-up slurry | 1.03–1.10 t/m³ (30–100 kg/m³ bentonite) | 9.0–10.5 | Na-bentonite, polymer modifiers | Yield point 5–15 Pa, Marsh viscosity 35–55 s |
| Return slurry (TBM discharge) | 1.15–1.45 t/m³ | 8.5–10.0 | Bentonite + ground cuttings (sand/gravel/clay) | Particle size from sub-µm clays to 100 mm cobbles |
| Reject solids (post-separation) | 40–65% w/w DS | 8–9 | Granular spoil; minimal clay | For landfill or beneficial reuse |
| Groundwater ingress | 5–500 mg/L TSS | 6.5–8.0 (site-specific) | Silt, occasional Fe/Mn | Volumes up to 1,000 m³/h on hard-rock TBMs |
| Grout / shotcrete bleed water | 500–5,000 mg/L | 11.5–13.0 | Ca(OH)2, cement fines | pH neutralisation with CO2 or H2SO4 mandatory before discharge |
| Equipment washdown | 200–2,000 mg/L; 50–500 mg/L FOG | 6.5–9.0 | Mineral oils, hydraulic fluid, grease | Treat via oil-water separator + DAF before reuse/discharge |
Vibrating screens (3–5 mm) → desanders/hydrocyclones (74 µm cut) → desilters (37 µm) → decanter centrifuge (clay/fines, 2–5 µm). Each stage drops slurry density by 0.05–0.10 t/m³. Properly cascaded, >95% of bentonite is recovered for recirculation, cutting chemical requirements by 60–80%.
Bentonite slurries behave as Bingham plastics: τ = τy + μp·γ̇. The yield point τy (5–15 Pa) is what keeps cuttings suspended at zero shear — critical for face support during stoppages. Plastic viscosity μp sets the pump head; gel strength (10-second and 10-minute thixotropic recovery) prevents cutting settlement in stand-pipes.
Discharge consents typically require pH 6.0–9.0, TSS <30 mg/L, NH4-N <1 mg/L. Grout bleed water at pH 13 requires staged CO2 sparging (cheap, no chloride/sulphate added) or H2SO4/HCl (faster but adds counter-ion). 1 m³ of pH 13 grout water carries ~0.5 kg of equivalent OH− — size CO2 capacity for 1.1× that load.
Specialised equipment engineered for the demanding conditions of tunnelling and underground construction.
Coarse screening to remove debris and large solids from TBM slurry and construction runoff. Heavy-duty design for continuous operation.
Debris RemovalHigh-efficiency grit removal to protect downstream equipment from abrasive sand and soil particles in tunnelling water.
Equipment ProtectionCompact clarification for suspended solids removal with 70% smaller footprint than conventional clarifiers. Ideal for confined construction sites.
70% Smaller FootprintDissolved air flotation for oil and grease removal, fine particle separation, and treatment of equipment washdown water.
Oil SeparationLow-energy dewatering of excavated spoil and sludge from tunnelling operations. Produces stackable cake for easy disposal.
Volume ReductionMobile treatment systems in standard containers for rapid deployment, easy relocation, and minimal site preparation.
Rapid DeploymentEqualization tanks for TBM slurry and groundwater storage with sediment control. Essential for managing variable flow rates.
Flow ManagementFlocculation and settling vessels for chemical conditioning and treatment of tunnelling wastewater with rapid solids separation.
Chemical TreatmentWe work with contractors, engineers, and project developers on underground construction water treatment challenges across diverse project types and geographies.
Supporting large-scale rail infrastructure with TBM slurry treatment, groundwater management, and construction runoff control systems.
Providing water treatment solutions for metro construction and operational wastewater management in urban environments.
Delivering high-capacity dewatering and slurry treatment for deep tunnel construction through complex geological conditions.
Supporting underground mining with dewatering and process water treatment systems for remote and challenging locations.
Engaging with urban subway expansion projects requiring comprehensive water treatment and environmental compliance.
Supplying treatment systems for cable tunnels, sewer tunnels, and other underground utility infrastructure projects.
Water treatment solutions for major infrastructure tunnel projects including road, rail, and subway systems. Reynolds & Bauhm systems handle high volumes of groundwater and construction runoff with full regulatory compliance.
Underground mining operations requiring dewatering and process water treatment in challenging conditions. Reynolds & Bauhm provides robust systems for remote locations with high solids loading.
Treatment systems for cable tunnels, sewer tunnels, and other utility infrastructure projects. Compact designs for confined spaces with mobile deployment options.
Water management during construction of dams, penstocks, and underground powerhouses. High-capacity systems for major civil works with environmental protection.
Tunnel construction water treatment requires robust process tanks.
Balance tanks for variable slurry flows and groundwater inflow.
View Equalization TankspH correction vessels for grout bleed water and alkaline runoff.
View Neutralisation TanksPackaged, containerised, skid-mounted and research-station families engineered for sites with no road, no grid, no operator and no local supply chain.
All five product families plus the engineering choices that span the catalogue — transport envelopes, off-grid power, satellite SCADA, swap-on-failure spares.
Read the HubComplete plants delivered as a single pre-commissioned package — villages, mining camps, expedition bases.
Read More10′, 20′ and 40′ ISO container plants hardened for hurricane, arctic, desert and salt-air environments.
Read MoreModular skids sized to helicopter sling-loads, 4×4 trailers and ATV sleds for sites with no road access.
Read MoreIn-depth guides to the principal water and equipment challenges on underground construction projects and the methods used to manage them
Slurry separation plant design: screening, hydrocyclone desanding, centrifuge dewatering and closed-loop bentonite recovery for slurry TBM drives.
View GuideTreating variable groundwater ingress: turbidity removal, iron and manganese precipitation, pH correction and oil interception before discharge.
View GuideAttenuation, coagulated lamella clarification and pH/oil correction for weather-driven site stormwater.
View GuideSafe, self-limiting CO2 and acid neutralisation of strongly alkaline shotcrete, grout and concrete-contact water.
View GuideCoalescing separation and DAF for oily, detergent-laden washdown water, with recycling for wheel-wash and washdown reuse.
View GuidePolishing, online monitoring and closed-loop reuse to hold every stream within consent and cut mains water demand.
View GuideContact Our Engineers for specialised underground water treatment solutions with Global Standards Reference support.
Site compound and treatment plant layouts for TBM slurry and groundwater treatment.
View ServiceField-verified as-builts for temporary and permanent tunnel services documentation.
View ServicePlan and elevation drawings for tunnel dewatering, grout, and ventilation pipework.
View ServiceComplete drawing services for civil engineering and tunnel construction projects.
View ServiceDedicated treatment systems tailored to the unique water challenges of rail, metro, alpine, mining, subway, and utility infrastructure projects.
TBM slurry treatment, groundwater management, and construction runoff control for large-scale rail infrastructure.
View Rail ProjectsWater treatment for metro construction and operational wastewater management in dense urban environments.
View Metro SystemsHigh-capacity dewatering and slurry treatment for deep tunnel construction through complex geological conditions.
View Alpine TunnelsUnderground mining dewatering and process water treatment for remote and challenging locations.
View Mining OperationsComprehensive water treatment and environmental compliance for urban subway expansion projects.
View Subway ExtensionsTreatment systems for cable tunnels, sewer tunnels, and other underground utility infrastructure.
View Utility InfrastructureOur expertise spans multiple industries with sector-specific water treatment solutions.