What is VersiTank®

VersiTank® infiltration/stormwater detention/stormwater retention tanks (i.e. modules) can be joint to establish a sub-surface infiltration system or an on-site stormwater detention tank system.

VersiTank® is a stormwater detention tank that is a man-made structure, meant to temporarily retain stormwater runoff. This stormwater runoff enters these ponds through a storm drain and is collected until the tank is full. The retained stormwater is then released at a regulated pace into surrounding aquatic bodies. This approach to stormwater management reduces floods in your towns and preserves coastal regions from erosion.

VersiTank® storm water tank provides an efficient at-source management system for rainwater harvesting and detention from roofs and other impermeable surfaces such as parking areas, driveways, playgrounds and sports fields.

VersiTank® storm water tanks are available in several sizes and load-bearing capacities catering for the requirement of individual houses up to the largest commercial and industrial developments in Singapore. The load-bearing capacity of each type may be increased with the use of additional proprietary “stabilisers”.

VersiTank® modules are easily assembled on site by clipping together lightweight, high strength interlocking panels. Assembled units can be interlocked both vertically and horizontally thereby ensuring the system remains stable under trafficable or high weight bearing load areas.

VersiTank® is a heavy duty plastic module that can be used as a void filler within planter boxes.

VersiTank® ideal for infiltration tanks, onsite stormwater detention tanks or onsite retention tanks.

PUB, Singapore’s National Water Agency has developed a set of technical guidelines to provide guidance to Qualified Persons on the design of detention tanks to manage peak runoff.


VersiTank® stormwater tanks allow sub-surface management of stormwater by infiltration, onsite detention or onsite retention in:


  • Residential homes
  • Parking areas and driveways
  • Playgrounds
  • Sports fields
  • Parks and gardens

VersiTank® acts as a retention system to allow water for re-use

VersiTank® offers several unique features incorporating:

  • High strength modules that allow use under trafficable areas
  • Small apertures in panels that minimise the risk of compacted soil and stones rupturing geotextile
  • Fewer tanks per unit volume compared to most other systems
  • The ability to cater for all volume requirements
  • Easy on-site assembly
  • Modules that interlock vertically and horizontally providing maximum stability
  • Lower cost than bio-swales, retention ponds and concrete tank

Stormwater infiltration and storage tanks offer benefits including:

  • On-site retention or detention of stormwater
  • Mitigation of downstream flooding
  • Catering for all volume requirements
  • Resistance to biological attack and to a wide range of soil-borne chemicals
  • Sub-surface installation that maximises site utilization
  • Allowing storm water to be filtered before infiltrating water tables or storm drains
  • More economic systems than bio-swales, retention ponds and concrete tanks
  • No specialised installation equipment required
  • Support US LEED™ credits

Infiltration System


Excavate an area to design specifications.


Ensure the base of the excavated area is level and compacted.


Lay down, level and compact a minimum 75 mm of coarse sand.


Place geotextile (minimum 250 g/m²) over the base and up the walls of the excavated area. Provide for a minimum 200 mm overlap and seal joints with adhesive PVC tape. Ensure sufficient geotextile overhang is available to cover the surface of the VersiTank®units after placement in the excavated area.


Position VersiTank® units on the geotextile in the excavated area.


Secure installed units with stainless steel fixing clips,tie wire or high strength plastic cable ties if necessary.


If required, another layer of VersiTank® units may be either placed on or interlocked beside the already positioned and secured units.


Form holes in the correct positions to receive both inlet and outlet pipes. Insert flanged connectors into both the inlet and outlet positions. Ensure that the outlet is positioned lower than the inlet.


Cover the sides and tops of the installed units with geotextile and seal overlaps around the inlet and outlet pipe areas with adhesive PVC tape.


Backfill on the sides and over the top of the VersiTank® units with a minimum 100 mm of clean coarse sand and compact using hand tools to engineering specifications.


Ensure a minimum 400 mm free-draining soil cover is applied on top of the 100 mm of clean coarse sand layer on the surface of the installed units to meet engineering and design authority specifications.
Re-Use System
1. Follow steps 1–4 above.
2. Ensure a minimum 300 g/m² geotextile is used.
3. Carefully position the impermeable membrane on the geotextile. The membrane must either be prefabricated to the required dimensions or be in sheet form of sufficient dimensions to completely envelope the installed VersiTank®.
4. Install a second layer of geotextile over the impermeable membrane. Care must be taken that the membrane is not damaged during installation.
5. Follow steps 5–8 (Infiltration System).
6. Ensure that the membrane joins on the top surface of the VersiTank® units and that inlet and outlet pipes are well-sealed using techniques recommended for the specific membrane.
7. Follow steps 9–11 (Infiltration System).

NOTE: VersiTank® Re-Use Systems must be installed by a competent waterproofing contractor who is skilled in the art of installing impermeable sheet membranes.

VersiTank® acts as an efficient stormwater infiltration or retention system

VT 553 VT 555 VT 840 VT 880
Size – L x W x H (mm) 500 x 500 x 250 500 x 500 x 500 745 x 395 x 425 745 x 790 x 425
Volume (m3) 0.063 0.125 0.125 0.25
Max load – unconfined (t/m2)*

– 1 centre panel

– 2 centre panels

– 3 centre panels

13 (VT 553-1) 10 (VT 555-1)

15 (VT 555-2)

18 (VT 840-3)

23 (VT 840-4)

27 (VT 840-5)

8 (VT 880-3)

10 (VT 880-4)

12 (VT 880-5)

Surface area (m2) 1.0 1.5 1.5 2.5
Surface void area (%) ~65 ~65 ~38 ~40
Internal void volume (%) ~95 ~95 ~93 ~93

* Safety factor of 1.5 included