Installing your new water tank

1. Above ground poly tank installation
2. Underground Latticeā„¢ Tank installation
3. Steel Tank installation


1. Above Ground Poly Tank Installation

Poly Tank Sitting Information

Correct Method for Sitting an Above Ground Poly Tank:

  1. Your Duraplas tank can be sited on LEVEL STABLE GROUND which has UNIFORM COMPACTION [free of soft spots] with a screeding of approx 75-100mm of sand or metal dust [approx 3mm stone]. The fill must be retained using some form of retaining structure eg [cement strip, rocks or treated pine sleepers etc ].

    water tank installation

  2. Alternatively your Duraplas tank can be sited on a reinforced concrete slab which must be 25mpa [approx 75-100mm thick with F72 mesh] that is level, flat and larger than the base of the tank. Consult an engineer for slab details.


Correct Method for Siting Tank 1/2 Way in Ground:

  1. Prepare hole. Ensure that the surrounding soil left in the walls of the hole is solid, leaving a (6-8 inch) 15 - 20 cm gap to allow positioning the tanks, and backfilling with sand or metal dust, stabilized with cement dust.

    water tank installation diagram crane

  2. If there is major water seepage into the hole from the surrounding soil, the site will not be suitable. Make sure tank site is drained well. Consult your engineer for drainage design.
  3. A base of 3-4 inches (7-10 cm) of sand or crusher dust must be put in the hole and compacted.
  4. Tank must be lowered into the hole squarely by crane.
  5. Tank must then be filled with water above ground height, then back filled with bedding sand or metal dust. Cement stabilize this fill medium.
  6. It is important that tanks be buried into ground up to ONLY one half of its wall height. (It is also recommended a Molasses grade tank for its extra wall thickness).
  7. It is recommended that your outlet pick up, from the tank, comes through the tank roof, or alternative plumbing from base outlet is needed.
  8. If there are 2 x 90mm inlets coming into the tank you will require at least 2 x 90mm overflow pipes.
  9. Overflow must be piped away from the tank.
  10. Please be aware Duraplas does not endorse its above ground tanks being buried, any damage incurring to the tank due to its burial will not be warranted, the above information is to be used as a guideline only. Please seek engineers advise.


Using a Tank Stand:

  1. It is recommended that you contact an engineer to ensure that a suitable stand is provided to meet any relevant requirements. Remember every litre of water is 1kg in weight.

    water tank stand


Do NOT Make these Errors:

  1. Rocky and uneven ground with little or no base preparation.

    water tank uneven ground

  2. Must not have undersized base. The total circumference of the tank must be supported. Ideally, allow the pad to be 100mm wider than the tank.

    water tank undersized base

  3. Wooden sleepers are generally too uneven and untrue to use for base.

    water tank wooden sleepers

  4. Don't use corrugated iron decking as a base.

    water tank corrugated iron


Important Points When Plumbing Tanks:

Tank Overflow:

  1. Always ensure that overflow water is plumbed away from the tank. This will reduce site erosion and ensure a sturdy support for the base of your tank. Regularly check the overflow screen and clean when necessary.


2. Underground Tank Installation

  1. Click here to view underground tank installation diagrams (PDF)
  2. Click here to watch the undergrand tank installation guide (VIDEO)


3. Steel Tank Installation

  1. Click here to view steel tank installation instructions (opens in new window)