Reclaimed Water Tank Data Center: Municipal Effluent Sourcing And Compliance

A reclaimed water tank for a data center stores treated municipal effluent - water that a wastewater plant has cleaned to a reuse standard - as a non-potable reserve for cooling-tower makeup. Sourcing reclaimed water turns a utility's discharge into a drought-resilient supply and is now common on water-stressed campuses. Center Enamel supplies Glass-Fused-to-Steel, Fusion-Bonded Epoxy and stainless bolted tanks with the inert finish and sealed roof that reclaimed-water duty requires, delivered to 100-plus countries. The tank sits between the utility delivery and the cooling loop, buffering variable reclamation flows and protecting the system from the carried load.

Reclaimed water is contracted from a wastewater utility under a reuse permit that defines the treated-effluent quality, the delivery schedule and the backflow and cross-connection rules. The authority having jurisdiction reviews the permit, the water-quality monitoring and the air-gap or backflow isolation before the loop runs. Because the incoming quality is defined by regulation rather than the data center, the tank and pretreatment are specified to that target, and the contract terms - not just the tank price - decide project viability.

• Reuse permit defines quality and delivery.
• AHJ reviews monitoring and isolation.
• Incoming quality set by regulation.
• Contract terms decide project viability.

Water stored for reuse, process or fire duty spends most of its life idle, so the internal finish decides reliability more than the shell rating. Glass-Fused-to-Steel panels are fired at 820-930 °C to give a smooth inert skin at 0.25-0.45 mm thickness, adhesion above 3,450 N/cm2 and 100 percent 1,500 V DC spark testing per panel. Fusion-Bonded Epoxy bolted tanks (Resicoat R4-ES interior 180-280 micrometres, Interpon D2015 exterior 150-250 micrometres, adhesion above 16 MPa) and hot-dip galvanized bolted tanks cover specified or cost-sensitive duties. Stainless 304 or 316 is chosen where the recovered water is low-mineral and a factory vessel is preferred. A caveat applies: the right lining depends on the recovered-water chemistry, so the engineer should confirm pH and halide load rather than assume one coating fits every reuse stream.

• GFS bolted: inert enamel, Ra below 0.8 micrometres, no field recoating.
• FBE bolted: documented epoxy lining for specified duty.
• Hot-dip galvanized: lower cost, zinc shell protection.
• Stainless 304 or 316 for low-mineral recovered water.

Sizing starts from the actual duty calculation - rainfall capture volume, cooling-makeup balance, greywater generation rate or fire hydraulic demand - not a catalogue number. The coating thickness of 0.25-0.45 mm for GFS or 180-280 micrometres for FBE, the tank lifecycle of 30-50 years, the NSF/ANSI 61 or WRAS potable-contact option and the freeze or tropical duty margin then set the shell, roof and appurtenances. Every figure below is confirmed against the applicable standard and the local authority having jurisdiction.

The figure below is a REAL Center Enamel delivery used here as manufacturing-capability evidence for the tank type discussed, NOT as a claimed data-center, rainwater, greywater, reclaimed, condensate or ice-storage project. Center Enamel's verified project record (case_library.csv) holds no data-center water-reuse, greywater, reclaimed-water, condensate-recovery or ice-storage delivery, so this reference demonstrates the ability to engineer large coated and stainless water tanks for demanding duty, not a claim about this specific application. Where the source did not record a diameter or height, the field reads Not Provided and is never estimated.

Size the buffer from the utility delivery schedule and the makeup demand so the tank smooths batch deliveries without overflowing or running dry. Keep the reclaimed loop isolated from potable by a mandatory air-gap, confirm the internal finish resists the specific chemistry (residual chlorine, pH, halides) of the effluent, and document the monitoring plan so the authority having jurisdiction can verify water quality continuously.

• Balance buffer against delivery and makeup.
• Mandatory air-gap from potable.
• Confirm finish against effluent chemistry.
• Document continuous monitoring for the AHJ.

A non-potable buffer that stores treated municipal effluent under a reuse permit and feeds cooling-tower makeup, turning utility discharge into a resilient supply.

Reclaimed water is treated municipal effluent from a utility under a permit, while greywater is on-site amenity water; reclaimed is delivered in batches and regulated externally.

A reuse permit from the wastewater utility defines the treated-effluent quality, delivery schedule and backflow and cross-connection rules.

An air-gap or backflow protection must separate the reclaimed loop from potable and utility systems so cross-contamination cannot occur.

GFS enamel gives an inert skin resisting residual chlorine and pH; FBE and stainless are alternatives where the effluent chemistry directs.

Continuous water-quality monitoring of the parameters set by the reuse permit, documented for the authority having jurisdiction.

From the utility delivery schedule and the steady makeup demand, so the tank smooths batch deliveries without overflowing or running dry.

Yes - GFS, FBE and stainless bolted tanks with the inert finish and sealed roof that reclaimed-water duty requires, delivered to 100-plus countries.

AWWA D103-09 and ISO 28765 for the bolted structure, with NSF/ANSI 61 or WRAS available where recovered water contacts potable-adjacent systems.

About 30 days ex-works for a 1,000-10,000 m3 tank, with on-site bolted erection in weeks versus months for concrete.

A verified single shell of 20,000 m3 was delivered in 2016, establishing the upper bound for one bolted tank.

Carried chemical load can corrode bare steel; documented 0.25-0.45 mm enamel or 180-280 micrometre FBE predicts long-term reliability.

Yes - the lining, not only the steel, should be warranted, because reclaimed-water duty stresses the coating over a 30-50 year life.

No - the fire reserve is a separate code-referenced volume and must stay isolated from the reclaimed loop.

Periodic internal inspection of the lining and verification of the monitoring plan support a 30-50 year service life.

A data-center reclaimed water tank stores permitted treated effluent between utility delivery and the cooling loop, buffering batch flows and protecting the system from the carried load. The reuse permit, air-gap isolation and continuous monitoring decide whether reclaimed water is a viable resilient supply, and those terms must be confirmed with the utility and the authority having jurisdiction before the tank is specified.