Square Modular Rainwater Tank for Underground Storage

A square modular rainwater tank can use available underground space efficiently where the site footprint is compact or regularly shaped. Interlocking PP cells form the internal storage structure and can be combined with geotextile, geomembrane, inspection and pumping components according to the project.

Square Modular Rainwater Tank Details

MaterialPolypropylene (PP)
Module size680 × 410 × 450 mm
Nominal unit volume0.125 m³
Modules per cubic metre8
Unit weightApprox. 8 kg
Published load reference25 t/m²
Typical functionsStorage, attenuation or infiltration

Square Modular Rainwater Tank for Underground Storage module details

How the Modular Tank Works

The PP units interconnect to create an open underground void. For a storage or reuse tank, the structure is normally enclosed with the specified geotextile protection and an impermeable membrane. For infiltration, the surrounding build-up is selected to allow water to disperse into suitable ground. In attenuation applications, the outlet is sized to release water at the project design rate.

Final depth, cover, access and allowable loading must be checked against the site conditions and the engineer’s design. Pretreatment should be included to reduce sediment entering the tank, while inspection and maintenance access should remain available after installation.

Installation Sequence

  1. Prepare a level excavation and the specified foundation.
  2. Install protective geotextile and membrane layers for the chosen tank function.
  3. Assemble and connect the PP modules to the approved layout.
  4. Form inlet, outlet, vent, inspection and pump connections as required.
  5. Wrap and seal the system, then place surround and cover material in controlled layers.
  6. Commission the system and establish an inspection and maintenance schedule.

Square Modular Rainwater Tank for Underground Storage installation guide

Project Applications and Support

Modular tank layouts can support residential, commercial, landscape, parkland and infrastructure projects. The correct system depends on runoff volume, available footprint, groundwater, soil conditions, traffic loading, maintenance access and the intended reuse or discharge method. We can coordinate module quantities, packing information and project-specific supply requirements from the drawings and design criteria provided by the customer.

Square Modular Rainwater Tank for Underground Storage project applications

Packing and Manufacturing

The lightweight modular parts are bundled for transport and assembled on site. Published packing references include 8 pieces per bundle for 680 × 410 mm components and 10 pieces per bundle for 450 × 410 mm components. Exact container quantities and production details should be reconfirmed for each order.

PP rainwater tank module packing

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