V5
26/10/2023
Page 5of 24
Installation - Below Ground
The method of installation is dependant of the site’s ground conditions.
Sites are divided into four categories:
Dry Site Where ground water or the water table does not rise above the base of the
excavation at any time of the year.
Wet Site Where ground water or the water table rises, or is suspected to rise, to 1,400mm or
less above the base of the tank.
Saturated Site Where ground water or the water table rises, or it suspected to rise, above the tank
outlet.
VORTEX S (Standard Duty) tanks are suitable for Dry and Wet sites where groundwater does not rise
above the base of the outlet (1.4m above the base of the tank).
VORTEX S tanks are white.
VORTEX H (Heavy Duty) tanks are suitable for Saturated sites where groundwater rises above the
base of the outlet (1.4m above the base of the tank).
VORTEX H tanks are black.
Do not undertake any concrete work if the temperature is likely to drop below freezing within the
following 24 hours.
Ensure the area is secure before undertaking any works.
It is essential that the VORTEX tank does not flood. The tank must be installed so that surface
water does not pool around the tank as this can cause the tank and Blower Tray to fill with water
(please note that the Blower Tray does have drainage holes). If there is any doubt, install the tank
so that the top of the turret is 25mm above ground level.
If required, a separate Blower Housing can be supplied.
Dry Site Installation
Excavate a hole that is 200mm greater than the diameter of the tank.
The excavation should be sufficiently deep so that the tank inlet is at the same depth as the
incoming drain from the building.
The tank must be placed a smooth, level and stable base. This base must be suitable for the site
specific ground conditions and soil structure. It must also be suitable for the operating weight of the
VORTEX tank. The tank must be able to distribute its weight evenly across the whole base.
The base must be free of any sharp objects or other objects that may puncture the tank.
A 150mm reinforced C28/35 concrete base is often the preferred option for many sites
If the ground contains high levels of contaminants, including for example sulphate or chloride, this
concrete mix will not be suitable. In these circumstances the advice of a qualified civil or structural
engineer should be sought.