Super Duty Super Duty

Super Duty

Super Duty from Promax. ENDURO underground tanks with thicker walls for higher loads. 18 tanks from 2,000L to 10,000L, 1 m diameter. Available in standard and TankGuard variants (with antimicrobial protection). For sites with heavy or rocky soil, high groundwater levels, and projects with increased strength requirements. Manufactured at the Promax factory in Kerikeri, available on the North Island only. 10-year pro-rata warranty. Made in New Zealand.

For standard underground tanks, see Underground Tanks. For above-ground tanks with increased rigidity, see ENDURO.

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10,000L Underground Tank 1m Dia Super Duty TankGuard - ENDURO

10,000L Underground Tank 1m Dia Super Duty TankGuard - ENDURO

P.O.A
P.O.A
10,000L Underground Tank 1m Dia Super Duty - ENDURO

10,000L Underground Tank 1m Dia Super Duty - ENDURO

$10,135.00
$10,135.00
9,000L Underground Tank 1m Dia Super Duty TankGuard - ENDURO

9,000L Underground Tank 1m Dia Super Duty TankGuard - ENDURO

P.O.A
P.O.A
9,000L Underground Tank 1m Dia Super Duty - ENDURO

9,000L Underground Tank 1m Dia Super Duty - ENDURO

$9,497.00
$9,497.00
8,000L Underground Tank 1m Dia Super Duty TankGuard - ENDURO

8,000L Underground Tank 1m Dia Super Duty TankGuard - ENDURO

P.O.A
P.O.A
8,000L Underground Tank 1m Dia Super Duty - ENDURO

8,000L Underground Tank 1m Dia Super Duty - ENDURO

$8,845.00
$8,845.00
7,000L Underground Tank 1m Dia Super Duty TankGuard - ENDURO

7,000L Underground Tank 1m Dia Super Duty TankGuard - ENDURO

P.O.A
P.O.A
7,000L Underground Tank 1m Dia Super Duty - ENDURO

7,000L Underground Tank 1m Dia Super Duty - ENDURO

$7,986.00
$7,986.00
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What Is Super Duty

Super Duty is a variant of the ENDURO underground tank with thicker walls. The additional wall thickness provides increased resistance to soil pressure, traffic loading and hydrostatic pressure from groundwater.

Super Duty is recommended for:

  • Sites with heavy clay or rocky soil
  • Locations with high groundwater levels
  • Installation under driveways or vehicle traffic zones
  • Projects with increased structural strength requirements

Super Duty Range

18 tanks in two configurations:

Super Duty Standard. 9 capacities from 2,000L to 10,000L. Thicker walls without additional coating. Prices from $3,294 (2,000L) to $9,745 (10,000L).

Super Duty TankGuard. 9 capacities from 2,000L to 10,000L. Thicker walls with TankGuard antimicrobial coating for drinking water. Price on application.

All Super Duty tanks: ENDURO series, 1 m diameter, rectangular shape for underground installation. Available on the North Island only (Kerikeri factory).

AS/NZS 4766:2020 Certification

ENDURO Super Duty is the only underground tank in New Zealand certified to AS/NZS 4766:2020 for permanent hydrostatic pressure resistance and full submersion. This means the tank performs even in fully waterlogged soil, where groundwater permanently surrounds the shell.

Hydrostatic pressure compresses an empty tank from the outside. Without sufficient wall thickness, a tank can deform or collapse. Super Duty is engineered to withstand this pressure for the full service life.

At Hobsonville Point (Auckland), a 3,000L ENDURO Super Duty tank was installed under a driveway with reinforced concrete surfacing. The tank withstands traffic loading from above and hydrostatic groundwater pressure simultaneously.

Super Duty vs Standard Underground

Super Duty:

  • Wall thickness: increased
  • Heavy soil: yes
  • High groundwater: yes
  • Vehicle traffic above: yes
  • Warranty: 10 years

Standard Underground:

  • Wall thickness: standard
  • Heavy soil: conditional
  • High groundwater: conditional
  • Vehicle traffic above: no
  • Warranty: 10 years (ENDURO) / 5 years (XPRESS)

For standard soil conditions and installation, a regular ENDURO or XPRESS underground tank is sufficient. Super Duty is needed when site conditions require additional strength.

When do I need Super Duty instead of standard?

If your site has heavy, rocky or clay soil, high groundwater levels, or the tank will be installed under a vehicle traffic zone. Your drainlayer or engineer will advise whether Super Duty is needed for your project.

Is Super Duty Available on the South Island?

Yes. Super Duty tanks can be supplied to the South Island, however they are manufactured at the Promax factory in Kerikeri, so additional freight charges will apply. Contact Promax for pricing and delivery options to your site.