Reliable municipal wastewater treatment — inlet works, primary, biological and tertiary stages engineered for consent compliance and capacity upgrades.
CFD, P&ID, SCADA and commissioning for critical water treatment plants.
Plant layouts, piping isometrics and construction-ready engineering drawings.
Flow, mixing and thermal CFD across treatment and process equipment.
Full mechanical, physico-chemical, biological and sludge equipment range.
See how we intensified an existing municipal plant with MBBR to add capacity and meet a tighter discharge consent — without constructing a new tank.
Read the Case StudyServing Communities Worldwide
Municipal wastewater treatment is essential for protecting public health and the environment. Our reliable, proven solutions help municipalities meet discharge requirements, reduce environmental impact, and optimise operational costs. From small communities to large cities, Reynolds & Bauhm provides scalable treatment systems that deliver consistent performance.
Solutions engineered for communities ranging from small villages to major metropolitan areas with millions of residents.
Explore Municipal PopulationSystems engineered to handle diurnal and seasonal flow variations typical of municipal sewage.
Explore Flow VariationsTreatment systems that protect receiving waters and support sustainable water management.
Explore Municipal EnvironmentalMeeting stringent discharge standards for BOD, TSS, nitrogen, phosphorus, and pathogens.
Explore Municipal ComplianceFrom population equivalent to design flow — the numbers behind every WWTP sizing
Municipal wastewater is dominated by domestic sewage diluted by infiltration/inflow (I/I). Per-capita loadings have been remarkably stable in European literature for four decades, and remain the reliable starting point for design when site sampling is not yet available.
| Parameter | Per Capita Load (g/cap·d) | Raw Sewage (mg/L) | EU UWWTD Discharge Limit |
|---|---|---|---|
| BOD5 | 50 – 70 | 200 – 400 | 25 mg/L (or 70–90% removal) |
| COD | 110 – 130 | 400 – 800 | 125 mg/L (or 75% removal) |
| TSS | 60 – 90 | 250 – 500 | 35 mg/L (or 90% removal) |
| Total Nitrogen | 10 – 14 | 40 – 80 | 10–15 mg/L (sensitive areas) |
| Ammoniacal-N (NH4-N) | 7 – 10 | 30 – 60 | typically <5 mg/L |
| Total Phosphorus | 1.5 – 2.5 | 6 – 14 | 1–2 mg/L (sensitive areas) |
| Hydraulic load (DWF) | 150 – 250 L/cap·d | — | — |
Plants are not sized for average dry-weather flow but for the diurnal peak and storm peak:
Why sensitive-water plants need the right reactor configuration, not just larger tanks
Two-step autotrophic oxidation: NH4+ + 1.5 O2 → NO2− + 2 H+ + H2O (Nitrosomonas) then NO2− + 0.5 O2 → NO3− (Nitrobacter). Net: 4.57 kg O2/kg N and 7.14 kg alkalinity (as CaCO3)/kg N consumed. Nitrifier μmax ≈ 0.7 d−1; requires SRT ≥ 8 d at 20 °C, ≥ 15 d at 10 °C, DO ≥ 2 mg/L.
Heterotrophic reduction in anoxic zone: NO3− + organic C → N2 + CO2 + H2O. Recovers 2.86 kg O2/kg N and 3.57 kg alkalinity/kg N — halving aeration energy if recirculation ratios are sized correctly. C:N ≥ 5 needed; on low-COD wastewaters supplement with methanol (2.47 kg MeOH/kg N) or acetate.
Precipitation with iron salts: FeCl3 + PO43− → FePO4↓ + 3 Cl−. Stoichiometric Fe:P = 1.8 (mol) or 3.2 (mass); practical doses 1.5–2.5× stoichiometric account for competing OH− consumption. Aluminium analogue: Al:P = 1.0 mol, 0.87 mass. Effluent TP < 1 mg/L is routine; < 0.1 mg/L requires post-filtration.
Polyphosphate-accumulating organisms (PAOs) released P in the anaerobic zone consume VFAs and store them as PHB, then over-take up P in the aerobic zone. Net P removal up to 3–5% of MLVSS — eliminates ferric demand and produces a P-rich waste activated sludge suitable for struvite (MgNH4PO4·6H2O) recovery.
Municipal Treatment Scenarios
Large-scale municipal WWTPs serving urban populations with comprehensive treatment processes.
Explore Municipal CentralisedCompact, efficient solutions for villages and small towns with limited resources.
Explore Small CommunitiesModular treatment units for remote areas, subdivisions, and cluster developments.
Explore Municipal DecentralisedRetrofit and expansion solutions to increase capacity or improve effluent quality.
Explore Municipal UpgradesCombined sewer overflow (CSO) treatment and wet weather flow handling.
Explore Municipal StormwaterAdvanced treatment for reclaimed water applications including irrigation and industrial use.
Explore Municipal ReuseComprehensive Municipal Approach
Screening and grit removal to protect downstream equipment from debris and abrasive materials.
Sedimentation and clarification to remove settleable solids and reduce organic load.
Products for Municipal Applications
Bar screens, spiral screens, and drum screens for reliable inlet protection and solids removal.
Efficient grit removal to protect downstream equipment and reduce abrasive wear.
Compact primary and secondary clarification with 90% space benefits vs conventional tanks.
MBBR, SBR, and MBR systems for effective BOD removal and nutrient reduction.
Effective solids separation for tertiary treatment and phosphorus removal.
Multi-disc presses and screw presses for efficient sludge volume reduction.
Automated polymer preparation for optimised solids separation and dewatering.
Polishing filtration for tertiary treatment and water reuse applications.
Advanced automation and monitoring for reliable plant operation and compliance.
Equalization tanks, stormwater storage, and emergency overflow containment with leak detection systems.
Contact tanks for disinfection, flocculation tanks, and aeration basins for advanced biological treatment.
Explore Other Industries We Serve
Pre-treatment systems for industrial facilities discharging to municipal sewers.
View Pre-Treatment SolutionsPre-treatment solutions for RO protection and membrane filtration systems.
Desalination Plant SolutionsWastewater treatment for food manufacturing with high organic loads.
Food Processing SolutionsWater treatment for construction dewatering and tunnelling projects.
Metro & Tunnelling SolutionsWhy Choose Reynolds & Bauhm
Municipal wastewater treatment requires a range of process tanks and vessels.
Chlorine contact tanks for disinfection retention time and pathogen inactivation.
View Contact TanksBiological aeration tanks for activated sludge and biofilm processes.
View Aeration TanksAeration is the single largest electrical load at most municipal plants — design choice has major Operating expenditure impact.
Fine-bubble membrane diffusers for activated sludge and nitrification.
Read MoreCost-effective treatment for small communities and decentralised plants.
Read MoreKLa, OTR and alpha/beta/theta corrections behind sizing.
Read MoreAerate raw water before treatment to cut chemical demand and DBP formation.
Read MoreContact our experts to design a solution for your community.
Our expertise spans multiple industries with sector-specific water treatment solutions.
Explore closely-related topics, equipment and guides
Send your influent analysis and our engineers assess your process and recommend a tailored treatment solution — free, confidential and no obligation.
Select the regulatory standard for your country — it sets which parameters we need for a compliance-aware process assessment.
Required parameters for the chosen standard are flagged on the sample form. You can still submit a partial set and we will advise what else to test.
Your sample is stored against your company so we can track the project. Provide a company name or email as a minimum.