Seismic & Engineered Tanks Seismic & Engineered Tanks

Seismic & Engineered Tanks

Promax engineered water tanks and seismic solutions for commercial, industrial, and infrastructure projects. Industrial Tanks in the ENDURO and XPRESS series from 450L to 30,000L with increased wall thickness. Cone Tanks for chemical dosing and wastewater treatment. Tanks for shipping containers, process systems, and bulk tank farms. Seismic restraints for Importance Levels IL1, IL2, IL3. PS1 documentation for engineered design. Promax can supply PS1 documentation (available at additional cost, contact us for details). 10-year pro-rata warranty. Designed and manufactured in New Zealand.

For standard above-ground tanks, see Large Water Tanks. For underground installation, see Underground Tanks.

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30,000L Industrial Tank - XPRESS in Mist Green, Image 1

30,000L Industrial Tank - XPRESS

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25,000L Industrial Tank - XPRESS in Mist Green, Image 1

25,000L Industrial Tank - XPRESS

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15,000L Industrial Tank - XPRESS in Mist Green, Image 1

15,000L Industrial Tank - XPRESS

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10,000L Industrial Tank - XPRESS in Mist Green

10,000L Industrial Tank - XPRESS

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3,500L Industrial Tank - XPRESS in Mist Green

3,500L Industrial Tank - XPRESS

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2,500L Industrial Tank - XPRESS in Mist Green

2,500L Industrial Tank - XPRESS

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30,000L Industrial Tank - ENDURO in Mist Green, Image 1

30,000L Industrial Tank - ENDURO

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25,000L Industrial Tank - ENDURO in Mist Green, Image 1

25,000L Industrial Tank - ENDURO

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Why You Need Engineered Tanks and Seismic Restraints

New Zealand experiences approximately 50 earthquakes of magnitude 5 and two of magnitude 6 every year, four of magnitude 7 every decade (GeoNet data). After the 2016 Kaikoura earthquake, concrete tanks in Ward (Marlborough) suffered serious damage and were replaced with Promax tanks. Polyethylene is more flexible than concrete and fibreglass: instead of cracking, the material deforms and returns to shape.

Seismic engineered tanks are required for projects with NZ Building Code and AS/NZS:1170 requirements. Seismic restraints anchor the tank to a concrete slab, preventing movement during earthquakes, cyclones, and floods.

Where engineered tanks and seismic restraints are needed:

  • Hospitals and critical infrastructure (Importance Level 4)
  • Commercial buildings: supermarkets, shopping centres, office complexes (IL2, IL3)
  • Industrial sites: dairy factories, processing plants, logistics bases
  • Subdivisions and residential complexes with council requirements
  • Wastewater treatment systems and balance tanks
  • Bulk water storage for fire protection and backup water supply

Industrial Tanks: ENDURO and XPRESS

Industrial tanks with wall thickness increased for design loads and/or construction weight requirements. Promax engineers support the project from design through to installation.

ENDURO Industrial Tanks. Corrugated walls for increased rigidity. Capacities from 450L to 30,000L. Low Profile option for 5,000L. 10,000L available on the North Island.

XPRESS Industrial Tanks. Smooth walls, one-piece construction. 6 capacities from 2,500L to 30,000L. 10,000L available on the South Island.

Industrial tank applications:

  • Flood Wash Tanks
  • Bulk Fire and Rain Harvest Retention Storage
  • Process Water Collection and filtration
  • Wastewater Treatment Processing
  • Bio Reactor and Balance Tanks
  • Effluent Collecting and Settling Tanks

Cone Tanks

Cone Tanks with a steep 50 degree cone for dry bulk and liquid storage. 4 capacities: 1,000L, 2,500L, 3,500L, 5,000L. Galvanised steel frame. Food grade polyethylene, chemically resistant, HSNO approved. Inlets and outlets configured to suit your system.

Applications: wastewater plants, food processing, chemical dosing.

Custom Engineered Solutions

Promax designs and builds custom tanks for specific project requirements.

Shipping Container Tanks. Tanks designed to fit inside shipping containers. Maximise storage volume in a confined space.

Liquid Process Tanks. A wide range of sizes and configurations with fittings and accessories to suit your project requirements.

Bulk Water Tank Farm. Multiple tanks connected into a single system for large-volume storage. Firefighting protection, commercial stormwater mitigation, municipal water treatment, wastewater processing, balance and effluent tanks.

Seismic Restraints

Promax seismic restraints are engineered to meet virtually all seismic loading requirements in New Zealand. For tanks from 1,000L to 30,000L. Meet BRANZ Seismic Resilience criteria.

Rating by Importance Level:

  • IL1: low-risk buildings (sheds, barns)
  • IL2: standard residential and commercial buildings
  • IL3: buildings with increased public significance, large crowd gatherings

PS1 documentation available at additional cost. Contact Promax for details.

Slimline Seismic Bracing Set. For Slimline 3,000L and 5,000L tanks. Seismic coefficient up to 1.1G. A simple add-on to the standard Slimline Tank.

Seismic Expansion Joints. Flexible connections for all fittings at the inlet and outlet of polyethylene tanks. Protect against leakage and stress. Rubber Bellows, threaded, Table D, E, ANSI.

Proven in Critical Infrastructure

Promax tanks are installed at critical infrastructure sites throughout New Zealand.

Taranaki Base Hospital, New Plymouth. 6 x 30,000L Industrial Tanks for backup water supply and fire protection. Importance Level IL4: facilities that must remain operational immediately after an earthquake. Months of consultation and design, delivered on time and on budget.

Burwood Hospital, Christchurch. 3 x 30,000L Industrial Tanks for backup water supply. The first major government project following the Canterbury earthquakes of 2011.

Countdown Bayfair, Tauranga. A 50,000L XPRESS tank and a 3,000L industrial tank with seismic restraints. A rainwater harvesting system collecting water from the supermarket roof. IL2 rating.

Fonterra Edgecumbe. 4 x 30,000L Industrial Tanks. Seismic anchor plates for sliding resistance to AS/NZS:1170, seismic coefficient 0.75g.