Visakhapatnam's proposed air-cooled data centre changes the wastewater design basis
A data centre in Visakhapatnam needs treatment for domestic sewage, wastewater reused for landscaping and flushing, and any cooling blowdown generated if wet cooling is installed. The planned AdaniConneX–Google campuses are reported to use air cooling, so cooling blowdown may be limited or absent, but domestic wastewater still requires an on-site treatment and reuse train. A 2026 life-cycle study found that UF+RO reuse used over five times the energy of freshwater treatment, although higher cycles of concentration reduced blowdown and chemical use. Final design should follow the actual water balance, source quality, reuse targets, discharge route, and reservoir-risk constraints.
New Indian Express reported on October 18, 2026, that the campuses at Mudasarlova and Tarluvada form part of a proposed development with a capacity of about 1 gigawatt. The reported design uses air-cooled systems rather than conventional evaporative cooling and cooling towers. That distinction matters: it removes the conventional cooling-tower blowdown stream from the base-case design, provided no separate liquid-cooling loop requires water treatment.
The same report states that freshwater consumption across the three sites is expected to remain below the volume of an Olympic-sized swimming pool and that around 80% will support landscaping, kitchens, and worker facilities. Domestic sewage will still require on-site treatment, disinfection appropriate to the intended reuse, storage, and controlled reuse. The project report also states that no treated wastewater will be discharged into the Mudasarlova Reservoir.
Air cooling therefore changes the wastewater design basis; it does not eliminate wastewater management. The wider planning context also argues for modularity: the state government said an expanded 6.5-gigawatt data-centre ecosystem could require around 3 TMC of water annually, according to New Indian Express, October 18, 2026. The remaining decisions are the final cooling architecture, wastewater flow and quality, reuse obligations, residual-management route, and treatment capacity needed for each campus phase.
Separate the wastewater and cooling-blowdown streams before selecting equipment
A defensible design starts by assigning each wastewater stream a source, destination, and treatment objective before comparing equipment. Combining sewage, cooling discharge, and process water into one common train can increase treatment energy, compromise reuse-water quality, and make residual handling less predictable.
Domestic wastewater means sewage from worker washrooms, kitchens, and related facilities. The reported project plan treats it on site and reuses it for landscape irrigation and toilet flushing. Cooling blowdown means concentrated discharge from cooling towers or evaporative coolers; it exists only if those systems operate. Process wastewater includes water affected by equipment cleaning, chemicals, or other operational activities and should not be assumed compatible with domestic sewage without source testing.
Prepare the following engineering inputs before sizing equipment:
- Average daily and peak flows for every source, including seasonal variation and construction phasing.
- Source-water analyses covering organics, suspended solids, dissolved salts, hardness, conductivity, corrosion indicators, and relevant chemical residues.
- Confirmed cooling technology, including any liquid-cooling loop for high-density IT equipment.
- Reuse fractions, application-specific water-quality limits, storage requirements, and operating schedule.
- Chemical inventory, cleaning procedures, drain destinations, residual route, and future expansion scenario.
For domestic wastewater, the normal sequence is screening, biological treatment, clarification, filtration, disinfection where required, storage, and reuse. A separate blowdown train should address its own chemistry. Process wastewater needs characterization before a route is assigned. The data centre cooling-blowdown treatment guide for Jabalpur provides a useful cross-site comparison, but local flow and quality data must remain the basis of design.
| Stream | Main sources | Required design basis | Potential route |
|---|---|---|---|
| Domestic sewage | Washrooms, kitchens, worker facilities | Average and peak flow, reuse targets, source analysis | Screening, biological treatment, clarification, filtration, disinfection, storage and reuse |
| Cooling blowdown | Cooling tower or evaporative cooler | Cycles of concentration, chemistry, flow, future cooling scenario | Segregation, recovery or concentration; disposal subject to approval |
| Process wastewater | Equipment cleaning and chemical activities | Constituent inventory, batch frequency, compatibility | Source-specific assessment before reuse or discharge |
Choose the cooling-blowdown strategy that matches the operating design
The no-blowdown case is valid only if the final campus design confirms that liquid cooling will not create a wastewater-bearing stream. The reported air-cooled design supports that case, but the design team should still test for separate liquid-cooling loops serving high-density IT equipment. Installing a large blowdown plant against an unconfirmed stream would create stranded capacity and unnecessary chemical, energy, and maintenance obligations.
If wet or hybrid cooling enters the design, characterize the discharge for suspended solids, hardness, conductivity, corrosion indicators, biocide residuals, and any site-specific reuse or permit conditions. The open question is not whether blowdown can be reused, but whether recovery improves the water and salt balance enough to justify treatment, concentration, and residual management.
Open Engineering Inc.’s 2026 life-cycle study, Reclaiming Cooling: Wastewater Reuse as a Strategic Resource for Data Center Water Management, found that increasing cycles of concentration reduced blowdown and chemical consumption. In its UF+RO scenario, wastewater-treatment energy use grew to over five times the freshwater case. Those findings support a comparison of recovery with concentration, not an automatic preference for desalination.
Request a complete water and salt balance before selecting the route. It should show makeup water, evaporation, drift, blowdown, recovery, residual volume, residual salt loading, and the consequence of each change in cycles of concentration. The project’s no-discharge commitment for treated domestic wastewater into the Mudasarlova Reservoir, reported by New Indian Express on October 18, 2026, makes the final destination a site-specific design constraint rather than a generic discharge assumption.
| Operating case | Trigger | Treatment decision | Principal risk |
|---|---|---|---|
| No cooling blowdown | Air cooling confirmed and no water-bearing liquid-cooling loop | Omit a dedicated blowdown train; retain space and interfaces for a future option | Unverified future wet-cooling change |
| Segregated blowdown | Wet or hybrid cooling confirmed | Characterize, segregate, and assess recovery or concentration | Membrane scaling, chemical residues, or residual accumulation |
| Reclaimed-water cooling feed | Water-quality and reliability criteria justify reuse | Compare UF+RO and alternatives against measured feed chemistry | Higher energy and concentrate disposal |
| Residual discharge | Only where legally and environmentally supportable | Confirm destination, approvals, monitoring, and no-reservoir-discharge commitment | Regulatory non-compliance and community objections |
Where pretreatment is justified, an ultrafiltration system for reclaimed wastewater pretreatment can protect downstream equipment from suspended solids and colloids. The equipment decision should follow the measured water envelope and recovery target, not precede them.
Design reuse treatment around the required water quality
Landscape irrigation and toilet flushing do not require the same treatment objective as high-pressure cooling feed or a tightly specified industrial reuse stream. Domestic sewage can therefore support these non-potable uses when it receives treatment, disinfection appropriate to the application, storage, and site-approved reuse controls. A biological treatment route is relevant where the campus needs an integrated sewage package; the integrated MBR wastewater treatment system can be evaluated as one candidate for that duty.
The 2026 Open Engineering Inc. study examined depth filtration, granular activated carbon, and chlorination as its primary reclaimed-water treatment train, with UF+RO assessed as an additional scenario. This comparison is useful for understanding treatment architecture, but the Visakhapatnam design must be based on local source water and the application-specific specification. A reuse specification that requires conductivity or dissolved-solids control is materially different from one defined only around turbidity and pathogen control.
UF is relevant where suspended solids, colloids, and microbial protection for downstream equipment are priorities. The ultrafiltration system for reclaimed wastewater pretreatment has stated 0.03-micron PVDF membranes, automatic backwash, and air scour. Those features do not replace feed-water characterization: biological variability, pretreatment quality, cleaning chemistry, and recovery requirements still determine suitability.
RO becomes more attractive when dissolved-solids control, conductivity reduction, or a high-quality reuse specification justifies its energy demand. The study reported UF+RO energy use at over five times the freshwater case. An industrial RO system for high-quality reuse water should therefore be compared on recovered-water value and concentrate management, not treated as the default treatment train.
Where reclaimed-water chemistry, biological variability, or industrial pretreatment could affect membrane performance, cleaning frequency, or recovery, require pilot testing or validated bench data. A monitoring schedule should cover flow, pH, conductivity, turbidity or suspended solids, residual disinfectant where used, and any parameter required by the reuse or discharge specification.
| Reuse or treatment objective | Evaluation emphasis | Key procurement evidence |
|---|---|---|
| Landscape irrigation and flushing | Domestic-sewage treatment, required disinfection, storage and reuse control | Reuse-water specification, flow range, treatment performance, monitoring and operating plan |
| Reclaimed water with suspended-solids protection | UF pretreatment and downstream reliability | Feed-water envelope, product-water quality, recovery, backwash and cleaning requirements |
| High-quality reuse requiring dissolved-solids control | UF+RO performance and concentrate route | Pilot data, conductivity and salt balance, energy consumption, membrane replacement and residual management |
| Cooling or process-water reuse | Application-specific chemistry and reliability | Complete source analysis, validation protocol, acceptance criteria and contingency route |
Assess energy, carbon, and zero-discharge trade-offs with a lifecycle view
A zero-discharge objective changes the design from selecting a treatment plant to managing every residual stream. It does not mean that installing a membrane system automatically produces zero liquid discharge. Domestic sewage, sludge, spent chemicals, membrane reject, cleaning wastewater, and concentrates each require a defined route and an accountable owner.
Open Engineering Inc.’s 2026 study found that the wastewater scenario had about twice the global warming potential of the freshwater case, with treatment energy accounting for roughly 80% of the difference. In the decarbonized-grid sensitivity case, carbon-equivalent emissions reduced significantly, but chemical production remained the main contributor. The procurement model must therefore include both energy and chemical impacts rather than claiming that either alone determines the preferred route.
The same study estimated an indirect water penalty of approximately 0.93 L/m³ for the reuse train. Open Engineering Inc. reported that this was less than 0.1% of the direct displacement benefit. For a Visakhapatnam campus, the commercial comparison should also include avoided freshwater demand, treatment energy, membrane replacement, chemicals, sludge and concentrate disposal, operator labour, reliability, and the consequences of a rejected reuse-water specification.
| Comparison item | Freshwater baseline | Reclaimed-water route | Evidence required from bidders |
|---|---|---|---|
| Water | Freshwater withdrawal and discharge | Recovered reuse and reduced withdrawal | Flow balance, recovery, make-up demand and site-specific sensitivity |
| Energy and carbon | Utility supply and associated emissions boundary | Treatment energy and chemical production | Specific consumption, load schedule and stated assessment boundary |
| Materials | No membrane replacement in the baseline | Membranes, media, chemicals and cleaning demand | Replacement interval, chemical inventory and operating hours |
| Residuals | Permitted discharge route | Sludge, concentrate and cleaning-waste routes | Residual mass balance, destination, approvals and contingency |
| Operations | Utility dependence | Plant availability, operator demand and maintenance | Redundancy, response time, training, spares and acceptance tests |
Compare alternatives over the same operating and residual boundary. Otherwise, a bid can appear inexpensive because energy, concentrate disposal, membrane replacement, or operator effort has been transferred outside the equipment price.
Build a procurement and compliance checklist for the Visakhapatnam site
The procurement package should convert the project’s water-balance assumptions into guaranteed, testable obligations. First, require each consultant and bidder to work from the same confirmed cooling technology, maximum campus water demand, phased implementation plan, reuse targets, and future wet-cooling scenario. A solution that assumes air cooling should identify what would change if liquid cooling or evaporative equipment is introduced later.
Require vendors to provide guaranteed flow ranges, feed-water envelope, product-water quality, recovery, energy consumption, chemical demand, cleaning requirements, redundancy, and monitoring scope. A nominal flow is not enough: acceptance criteria should connect equipment guarantees to the source-water and reuse-water specifications. Sampling plans, commissioning tests, operator training, spare-parts strategy, and maintenance response times should be contractual rather than left to installation practice.
Each bid must also identify the discharge destination, residual and concentrate management route, environmental approvals, and evidence of compliance with the project’s no-discharge commitment to the Mudasarlova Reservoir. If disinfection is included, define the generation method, dose or control strategy, monitoring, safety requirements, and operating response. The chlorine dioxide generator for controlled wastewater disinfection can be evaluated against those application requirements, but no generation technology should be accepted without source and reuse data.
Modular, segregated treatment trains reduce this risk: domestic reuse can operate while a future cooling-blowdown recovery or zero-liquid-discharge module is added or upgraded. The bid comparison should use the energy, carbon, water, blowdown, and chemical trade-offs identified in the 2026 Open Engineering Inc. study, together with site-specific cost inputs. Obtain current freshwater tariffs, disposal arrangements, energy tariffs, and residual-handling costs instead of accepting a generic life-cycle estimate.
| Bid item | Required submission | Acceptance focus |
|---|---|---|
| Design basis | Confirmed cooling mode, stream segregation, flow balance, source analyses and reuse targets | Assumptions traceable to current project information |
| Equipment guarantee | Flow, feed envelope, product water, recovery, energy, chemicals, cleaning and redundancy | Contractual guarantees under defined operating conditions |
| Residual management | Complete residual mass balance, destination, approvals and contingency | No unapproved discharge; no-reservoir commitment demonstrated |
| Commissioning | Sampling plan, acceptance tests, training and handover documents | Tests use representative source water and agreed reuse criteria |
| Lifecycle | Energy, carbon, chemicals, media, labour, residuals and freshwater comparison | Same assessment boundary for every bid |
Frequently Asked Questions
Is a cooling-blowdown treatment plant required for the planned Visakhapatnam campuses?
Not on the reported base-case design. New Indian Express reported on October 18, 2026, that the proposed campuses will use air cooling rather than conventional evaporative cooling and cooling towers. The engineering team should nevertheless confirm whether high-density IT equipment will use a separate liquid-cooling loop. If a water-bearing cooling stream is introduced, characterize and treat it as a separate stream rather than adding it automatically to the domestic-sewage plant.
How should domestic wastewater treatment capacity be sized?
Size each campus from separate average and peak-flow inputs, then subtract measured or contracted reuse where reuse is reliable. Add the treatment train required by each reuse destination, such as landscape irrigation or toilet flushing, and state the redundancy and phased-expansion basis. Request current hourly and seasonal flow data, rather than relying only on occupancy-based estimates. The final sizing also needs the reuse-water specification, storage and operating schedule, and a defined response for maintenance or peak loads.
Does the project need UF+RO for reclaimed wastewater?
Not unless the measured source-water envelope and reuse specification justify it. UF may be suitable for pretreatment where suspended solids, colloids, or downstream equipment protection dominate. RO becomes more relevant where dissolved-solids or conductivity control is required. Open Engineering Inc.’s 2026 study found UF+RO energy use at over five times the freshwater case, so the decision should also cover concentrate management, membrane replacement, chemicals, operator labour, and the value of the recovered water.
Which disposal route presents the lowest compliance risk?
The confirmed project route—on-site treatment and reuse of domestic wastewater, with no treated wastewater discharged into the Mudasarlova Reservoir—is the central design control reported by New Indian Express on October 18, 2026. Any alternative must demonstrate its own destination, approvals, monitoring and residual-management arrangement. A proposed discharge should not be treated as a lower-risk default simply because a treatment system is available; the reservoir and adjoining environmental concerns require a project-specific regulatory review.
What information should a supplier provide before equipment selection?
Require guaranteed flow ranges, feed-water envelope, product-water quality, recovery, energy consumption, chemical demand, cleaning needs, redundancy, and monitoring scope. Also request source and reuse sampling plans, commissioning acceptance criteria, operator training, spare-parts strategy, maintenance response times, and a complete residual-management route. A bid that omits any of these inputs cannot demonstrate that its equipment will perform under the campus’s actual water balance.
