Free interactive tool to estimate capital cost, operating cost, space requirements, and power consumption for your STP project in Kolkata and West Bengal.
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The capital cost of a Sewage Treatment Plant includes several major components. Understanding each helps you evaluate quotations and avoid hidden charges.
| Component | Share of Total Cost | Description |
|---|---|---|
| Civil Works | 25-35% | RCC tanks, foundations, channels, sump, pump house. Heavily influenced by soil conditions and water table level. |
| Mechanical Equipment | 30-40% | Blowers, pumps, diffusers, media (for MBBR), decanters, sludge handling equipment. The core of the treatment process. |
| Electrical Systems | 10-15% | MCC panel, VFDs, cabling, earthing, lighting. Includes automation panel for SBR systems. |
| Instrumentation | 5-8% | pH meters, flow meters, DO sensors, level sensors, SCADA system (if specified). |
| Piping & Valves | 5-10% | UPVC/HDPE/MS piping, SS valves, air piping, interconnections. |
| Installation & Commissioning | 8-12% | Erection, alignment, testing, biological seeding, performance trial, operator training. |
The choice of treatment technology significantly impacts both capital and operating costs. Here's how the four major technologies compare for Kolkata installations:
| Technology | Capital Cost/KLD | Operating Cost/KLD/Day | Space/KLD (sq.m) | Best For |
|---|---|---|---|---|
| Extended Aeration | ₹40,000 - ₹65,000 | ₹4 - ₹8 | 1.5 - 2.0 | Budget projects, large available space |
| MBBR | ₹50,000 - ₹80,000 | ₹5 - ₹9 | 0.8 - 1.2 | Best balance of cost, space, and performance |
| SBR | ₹60,000 - ₹90,000 | ₹5 - ₹8 | 1.0 - 1.5 | Variable flow, phased projects |
| MBR | ₹80,000 - ₹1,20,000 | ₹8 - ₹15 | 0.5 - 0.8 | Premium water reuse, space-constrained sites |
Operating costs are often underestimated during project planning. For a typical 50 KLD MBBR-based STP in Kolkata, monthly costs include:
| Item | Monthly Cost (50 KLD) | Notes |
|---|---|---|
| Electricity | ₹8,000 - ₹15,000 | Based on connected load of 8-12 kW, 18-20 hrs/day operation |
| Chemicals | ₹5,000 - ₹12,000 | Coagulant, flocculant, nutrients, disinfectant (chlorine/UV) |
| Manpower | ₹10,000 - ₹18,000 | One trained operator (shared or dedicated based on plant size) |
| Consumables | ₹2,000 - ₹5,000 | Lab testing kits, minor spares, lubricants |
| Sludge Disposal | ₹2,000 - ₹5,000 | Periodic sludge dewatering and disposal (varies by volume) |
| Total | ₹27,000 - ₹55,000 | Varies by inlet quality, technology, and operational efficiency |
Several local factors influence the final cost of your STP project:
Our calculator provides estimates. For a precise quotation with detailed BOQ, process design, and project timeline, contact our engineering team.
Request Free Site Assessment ✉ info@zexcorp.comSTP costs in Kolkata range from ₹5 lakh for small packaged units (5-10 KLD) to ₹50 lakh or more for larger custom-designed systems (100+ KLD). Key factors include capacity, treatment technology (MBBR, SBR, MBR), site conditions, and discharge quality requirements. Use our free calculator above for a personalized estimate.
The cost per KLD varies by technology and capacity. MBBR systems typically cost ₹50,000-₹80,000 per KLD, SBR systems ₹60,000-₹90,000 per KLD, and MBR systems ₹80,000-₹1,20,000 per KLD. Larger systems have lower per-KLD costs due to economies of scale. Extended aeration is the most economical at ₹40,000-₹65,000 per KLD.
Monthly STP operating costs in Kolkata include electricity (₹3-8 per KLD per day), chemicals (₹1-4 per KLD per day), manpower (₹8,000-₹25,000/month for an operator), and consumables. For a typical 50 KLD MBBR-based STP, expect monthly operating costs of ₹25,000-₹50,000.
Extended Aeration is generally the most affordable, followed by MBBR. However, MBBR offers the best balance of cost, space efficiency, and performance. For buildings with limited space, packaged MBBR systems are recommended as they have 40-50% smaller footprint than extended aeration of the same capacity.
Under WBPCB regulations and the National Building Code, buildings generating sewage beyond prescribed limits must install STPs. In Kolkata, buildings with more than 20,000 sq ft built-up area or generating more than 10 KLD of sewage typically require an STP for Occupancy Certificate (OC) and building completion approval. Contact our WBPCB compliance team for specific guidance.