Potable Water Reservoir Tank Lining

The challenge

A potable water reservoir tank corrodes on the inside where stored water sits against steel, and the original lining that held that corrosion back starts to break down. As the lining fails, the bare steel underneath pits and loses wall thickness, and the breakdown can carry into the water the tank is supposed to keep clean. Left untreated, the corrosion spreads, the tank can no longer protect the stored water, and it has to be taken out of the supply. The owner needed the interior brought back to a clean, protected condition with a lining suited to drinking-water contact, without replacing the tank.

The Belzona approach

The tank is drained and ventilated, then the interior is grit-blasted back to clean, profiled steel so the old failing lining and the corrosion product come off and the new system bonds to bare metal. A cold-applied composite rebuilds the pitted and thinned areas and brings the steel back to profile, with no hot work in the tank. An immersion-grade lining keyed to potable water contact then goes across the full interior, so the steel and the rebuilt areas sit under one continuous barrier. The lining is finished and inspected before the tank goes back into the supply.

1. Assess and mapThe drained tank is entered to map pitting, metal loss, and the condition of the old lining, and to confirm the interior is suited for a drinking-water-contact system.
2. Grit-blast prepThe full interior is grit-blasted to a clean, profiled surface so the failed lining and corrosion product come off and the new system bonds to bare steel.
3. Rebuild pitted steelA cold-applied composite rebuilds the pitted and thinned areas, restoring the steel to profile with no hot work.
4. Apply immersion liningAn immersion-grade lining suited to drinking-water contact goes across the steel and rebuilt areas as one continuous barrier.
5. Inspect and return to serviceThe lining is confirmed sound and continuous, and the tank is ready for return to the potable water supply.