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Portable Wash Bays

Wash bay construction and design

Need a permanent wash down area for your workplace that meets your local water authority’s regulations? Ensuring your workplace is environmentally compliant?

Trade Wash supply industrial wash-down equipment for permanent applications and can help in design and construction of your wash bay for your business. We can liaise with your contractors and issue engineered drawings for installation of our products.  Our permanent wash bays can incorporate a range of solutions such as oil water separators, demand driven wash down systems and first flush systems for those larger applications. Speak to us today for a no obligation free quote and consultation.

Wash bay design

What is a permanent wash bay?

Portable Wash Bay

A permanent wash bay is a dedicated area used specifically for the wash down of vehicles and equipment at your workplace that prevents water runoff from directly entering the stormwater network untreated. Essentially, any business responsible for vehicle and machinery wash down in any capacity requires a wash bay that is environmentally compliant according to local regulations.

In many cases, it makes sense to utilise a permanent wash bay that is purpose-built for vehicle and machinery wash down as this allows your workplace a long-term dedicated wash down area and holding tanks or water treatment options e.g. oil water separators, demand driven diversion systems and first flush systems (if required) can be isolated from other areas of the workplace, limiting the potential for accidental damage and providing easier access for maintenance requirements.

Portable wash bays

For smaller operations, job sites that are constantly on the move e.g. earthworks and mining or worksites that are leased and therefore do not allow for a more permanent construction our range of portable wash bays will be more suitable due to their simple assembly, dismantling and compact storage. Click here to read more about our portable wash bay products.

Portable Wash Bay

Wash bay construction

A permanent wash bay consists of the following components:

  • A dedicated area large enough for vehicle and machinery wash down
  • A bunded perimeter capable of retaining all excess water runoff as a result of any wash down activity.
  • A dedicated pump that transports all water runoff to either a holding tank or water treatment system.


Trade Wash can provide a range of bunding options including fixed rubber bunding (125mm x 42mm, shaped as to not be a tripping hazard) and flexible bundi5g which collapses and springs back to shape after being driven over, reducing the impact of vehicles such as forklifts crossing the perimeter.

In most cases fixed rubber bunding will be a better long-term solution for most businesses and Trade Wash can provide a range of vehicle ramp options for more efficient vehicular access.

Portable Wash Bay

Liquid storage

Bunded areas and wash bays can also be beneficial if you have a temporary liquid storage requirement or require a secondary liquid storage requirement e.g. in the case of the bunded area containing bunded spill pallets.

It is important however to ensure the storage capacity equals at least 110% of the largest liquid storage drum or meets your local authority requirements.


Water treatment options:

Oil water separator

Demand-driven wash down diversion system

First flush diversion system

Wash bay screens for drainage pits

Filter bags

Stormwater diversion systems for large and small applications

Geo bag filters

*Depending on your specific requirements you may find it more cost efficient to simply pump your wastewater runoff to a holding tank that can then be taken off site by a company specialising in the removal of contaminated water runoff. Alternatively, you may require one or a combination of water treatment options listed above should your demand require a water treatment option.

Roofed or unroofed wash bay construction?

The location and construction of your permanent wash bay should be carefully considered. In the majority of cases, the primary consideration is whether the permanent wash bay should be roofed or unroofed. In some cases, this will mean the construction of your permanent wash bay will take place under a pre-existing roof e.g. within a factory setting or a dedicated roof can be constructed. Alternatively, wash bays can be unroofed but some considerations will need to be taken into account and always check with your local authority on their preference. In some shire’s your council will prefer a roofed wash bay where possible.

We’ve listed some of the pros and cons associated with roofed V unroofed permanent wash bays below:

Roofed Wash Bay

Unroofed Wash Bay

Wash bay activity can be carried out even during non-conducive weather e.g. extreme heat, thunderstorms and rain events.

More cost-effective and quicker to construct as a ‘roof’ may require additional building permits.

As the wash bay is not exposed to the outdoors a roofed permanent wash bay will not require a diversion system to ensure environmental compliance.

Also unroofed wash bays  don’t have the costs for roof construction which 9 times out of 10 will be more expensive than a diversion system.

Height restrictions do not apply which is a consideration if working with heavy mining vehicles and machinery such as earth movers and cranes.

*In some instances e.g. if your wash bay is particularly large a roof may be required for environmental compliance. If you are unsure speak to us today. If you require your wash bay to be constructed in an unroofed area a first flush diversion system should be integrated into the permanent wash bay to ensure pollutants left on the surface of the wash bay are flushed to a treatment system during rain events preventing them from entering the stormwater network and protecting your business from being non-compliant.

Read more about our first flush products here.

Efficient wash bay design and construction

We can design and construct an efficient wash bay either under permanent cover or in an unroofed area of your workplace. Contact us today for a free no obligation consult and allow us to show you the most reliable and cost-efficient permanent wash bay options for your workplace.