Soakwell Cleaning and Maintenance

Why do soakwells stop working?

A soakwell will typically stop functioning for two reasons, either it is full of material and has no volume to contain the water or a thin layer of material, such as mud or hydrocarbon buildup, is preventing the water from soaking out into the sand.

If the issue is a result of manmade contamination the controlled waste soakwell cleaning procedure will be required.

All About Soakwells sucks out and maintains soakwells to get them flowing again.

Removing non contaminated waste from soakwells.

How do you clean a Soakwell?

For removing natural material we offer a cost effective alternative to utilising a vehicle registered for controlled waste, by having a vehicle dedicated to uncontrolled waste.

The vehicle has a top mounted boom with a high powered vacumn that swings around the radius of the truck. This requires access within 1.5m of the soakwell, no overhead restrictions and a width of 2.5m.

The operator sucks up the material while standing at the opening of the soakwell. Water may be required if the material is compact. In order to determine the depth of the soakwell (if unknown) the operator will carefully vacumn down one side until the base of the soakwell is exposed.

Soakwell and Pipe Cleaning

The diameter of the hose is 300mm. This means access is generally through a 550mm grate in the cover of the soakwell. If there is no grate access the only way to clean inside is to remove the cover (excavation required).

Soakwell maintenence considerations

  • Are there any smells or slicks to indicate the soakwell is contaminated?
  • Is the grate in the soakwell cover accessible, can it be opened or is it rusted?
  • How will traffic be affected by the cleaning. Each soakwell can take an hour on average.
  • How compact is the material, is the soakwell completely full or only a third?
  • If the water is not draining away, could it be due to the water table in the area? Is the ground type suitable?
  • Is the soakwell system adequete or is it being saturated? We can calculate the recommend volume and install additional soakwells as required.

This service is great for owners and property managers with drainage issues. Generally once cleaned a soakwell should be maintained every few years depending on the traffic around it.

Animation showing the difference betweeen a clean soakwell and a dirty one.

If issues persist our experience means we can provide a permanent solution, for example by performing a volume calculation and interconnecting additional soakwells.

 Tip! - Just a few hundred mm's of built up dust, mud or hydrocarbons can clog up a soakwell.

Spoil Disposal

If the waste is natural and does not pose a health risk there are no requirements to analyse it and dispose of it according to the strict regulations that govern controlled waste.

The vacuum fitted to the truck sucks up all debris including water from the soakwells. Spoil disposal is charged by the m3 (including water) and must be strictly free from any kind of contamination.

If possible, it can be more cost effective to wait until water has subsided before commencing the cleaning.

Removing non contaminated waste from soakwells. Soakwell Cleaning Cleaning soakwells all over Perth. Flooded carpark, soakwells need cleaning. A soakwell cleaning trucks sits in a flooded carpark.

Spoil Disposal Estimator (m3)

Spoil disposal is charged by the m3, including water. The amount of spoil is an estimate only and may vary based on the depth of the soakwell.

Estimate with the soakwell diameter and the approximate height of the spoil inside.


Internal Diameter of Soakwell
Approx. Height of Spoil (mm)
Number of Soakwells


Spoil per Soakwell (m3)
Spoil Total (m3)
Soakwell cleaning truck operating North of the river (Perth). Sometimes water is added to compacted soakwells to assist in the cleaning. Mini dumper can add clean sand to soakwells to replace what was removed.

What is Non-controlled Waste?

Only natural material (sand, leaves, mud ect.) should be present in soakwells.

Anything else could be considered contamination and needs to be assessed to ensure the correct transport and disposal process is used. This is because soakwells leach their contents into the water table.

The process used is called soakwell eduction.

Signs of contamination

  • Strong smells such as chemicals, rotting or fats,
  • Oily slick on surface of water or soakwell sides,
  • Fine particles such as sand blasting material or plastics,
  • Foaming.

If there are any signs a soakwell is contaminated, a different vehicle is required and there are some additional requirements, including a laboratory analysis of the material.

The operator removes material from the bottom until clean sand is reached or the bottom edge of the soakwell.

Sand Replacement

Each time a soakwell is cleaned, material is removed from the base. If the soakwell has not had significant foreign material enter, and has instead been cleaned due to an impermeable crust forming, then some fresh white washed sand may need to be added to prevent undermining in the future.

For future maintenance a soakwell should ideally retain a base of 250mm of clean sand. We have a mini dumper that allows us to transport and tip sand into each soakwell, neatly, safely and efficiently.

Sometimes additional sand may need to be added to the soakwell after cleaning.



 08 6406 2112

Soakwell Maintenance Summary

Soakwells should generally be maintained every two years to avoid a build up of hydrocarbons contaminating the sand.

In general an estimation of 1hour per soakwell can be used, as long it isn't too compacted or have a significant quantity of material. Ideally the cleaning will take place when they are not full of water.

The grates must be operable. It is quite common for older grates to rust, particulary if under brick. In a commercial environment, if a grate is rusted out then the soakwell cover should be replaced due to possible degredation of the frame inside the concrete.

Consideration needs to be given to traffic management while the cleaning is being performed. Vehicles will not be able to access the area while the equipment is operating.

In some situations soakwells may not be draining simply due to the water table in the area.