150 m3 Makeup Water Storage Tank: Design, Coating and Makeup Duty

A 150 m3 makeup water storage tank (roughly 39,600 US gallons) sits in the sweet spot for a single mid-size cooling tower or a process plant that needs a day or two of buffered make-up. It is large enough that coating and structure stop being afterthoughts, but small enough to stay a bolted-panel or shop-welded build. This article covers the design decisions that separate a tank that quietly runs for decades from one that needs re-lining at year eight.

A 150 m3 makeup water storage tank must be designed around its duty: a clean inert lining (GFS fired at 820-930 C or FBE) because the water feeds a potable or semi-potable loop, a bolted-panel or welded shell rated to AWWA D103 or ISO 28765, and wind and seismic calculations per the site (Eurocode in Europe, local code elsewhere). Confirm 304 or 316 stainless only where the loop is compact and high-purity. We have delivered mid-size coated clean-water tanks such as the 505 m3 Guyana potable array (2024, 3 x phi5.97x6m) and the 844 m3 Ghana potable project (2022); these are analogous mid-size references, not makeup or data-center projects.

Make-up water is corrosive enough to attack bare steel and to grow biofilm if the surface is rough. GFS gives a vitreous, inert face fused at 820-930 C; FBE is a factory powder coat with similar inertness; stainless is the compact alternative. Require a holiday test record and a chemical-resistance list matched to your water, because the lining, not the shell, sets service life.

• GFS or FBE inert lining.
• Holiday test on panels.
• Chemical-resistance list.
• Lining sets life.

A 150 m3 tank is a wind and seismic structure as much as a vessel. Design to AWWA D103 and ISO 28765 for bolted steel, with shell, anchor, and foundation loads calculated for the site; in Europe apply Eurocode (EN 1990-1999) and EN 1090 execution. For a pressurized make-up vessel, ASME Section VIII and the U-stamp scope are confirmed per project.

• AWWA D103 + ISO 28765.
• Eurocode / EN 1090 in EU.
• Wind and seismic calcs.
• ASME where pressurized.

Decide the buffer: a 150 m3 tank typically covers one to two days of make-up for a mid-size tower at 3-5 concentration cycles, but add margin for blowdown spikes and supply cuts. The tank should be accessible for level control and easy to isolate for cleaning, with an overflow sized to the fill pump.

• 1-2 days typical buffer.
• 3-5 cycles assumed.
• Margin for blowdown spikes.
• Isolation for cleaning.

A sealed roof keeps out debris and birds and limits evaporative loss from the buffer itself; an aluminum dome or membrane roof is common. Add a level transmitter to the BMS and a manway for inspection. These small choices prevent the tank from becoming a neglected, unmonitored point of failure.

• Sealed roof limits loss.
• Aluminum dome / membrane.
• Level to BMS.
• Manway for access.

We have no makeup-water or data-center project in this library. The mid-size coated clean-water tanks we cite (Guyana 505 m3 2024, Ghana 844 m3 2022) are analogous evidence of our mid-size bolted build, not makeup or data-center deliveries.

• No makeup / DC project.
• Citations analogous, not claims.
• Mid-size build is real.
• Duty needs your cycles.

Glass-fused-to-steel or fusion-bonded-epoxy for a clean inert surface, or 304/316 stainless for compact high-purity loops; require a holiday test and chemical-resistance list.

AWWA D103 and ISO 28765 for bolted steel, Eurocode and EN 1090 in Europe, with wind and seismic calculations; ASME Section VIII where it is a pressure vessel.

Typically one to two days of make-up for a mid-size cooling tower at 3-5 concentration cycles, with added margin for blowdown spikes and supply interruptions.

Yes, a sealed aluminum dome or membrane roof keeps out debris and birds and limits evaporative loss from the buffer itself.

A level transmitter to the BMS and a manway for inspection, so the tank is controlled and serviceable rather than a neglected point of failure.

Not in our project library. We cite mid-size coated clean-water tanks as analogous capability, not makeup or data-center deliveries.

A 150 m3 makeup water storage tank lives or dies by its lining and its calculations, not its volume. Choose an inert holiday-tested coating matched to your water chemistry, design the shell and anchor to AWWA D103, ISO 28765, and the local seismic and wind code, and treat the tank as a controlled, monitored asset with a sealed roof and level feedback. Get those right and the 150 m3 tank is a decades-long, low-maintenance buffer; skip them and it becomes a re-lining project.