Why should you drain the grey water from a motorhome ?

Grey water refers to all the wastewater from the sink, shower, and sometimes the washbasin in the vehicle. Unlike black water (which comes from chemical toilets), grey water still contains soap residues, detergent, and sometimes food particles.
If not drained regularly, this stagnant water can generate unpleasant odors, promote the growth of bacteria, and even damage the tank’s storage system.

Beyond hygiene and comfort on board, draining grey water is also a matter of respecting the environment. Discharging this water anywhere is strictly prohibited in France and Europe and can result in heavy fines.
Fortunately, thanks to the numerous service areas dedicated to motorhomes and converted vans, it is now easy to drain your vehicle while respecting nature.

At AVIS explore, all our vehicles are equipped with suitable tanks to safely store your wastewater. A thorough inspection is carried out before each departure to ensure a worry-free journey.

When and how often should you drain grey water ?

Proper maintenance of a motorhome involves regularly managing grey water.
But when exactly should you perform the drainage?
The answer depends on several factors, starting with the tank’s volume and the number of travelers. As a general rule, it is recommended to drain grey water as soon as possible when you find a service area.
This prevents the tank from filling completely, which could lead to unpleasant overflows or even damage.

For extended stays or remote travels in nature, draining every 2 to 3 days is recommended.
This schedule helps prevent bad odors and maintains good hygiene on board.
If you use cleaning products or cook frequently in the vehicle, consider adjusting this frequency. An essential tip for cold periods: never let grey water stagnate too long in winter.
The risk of freezing could damage the drain valve or crack the tank, leading to significant repair costs.

Finally, remember that draining grey water must be done only at authorized sites. Thanks to the numerous dedicated areas across France and Europe, you will always find a suitable place during your stops with AVIS explore.

Where to drain grey water legally ?

Draining grey water cannot be done just anywhere. It is the responsibility of every motorhome or campervan traveler essential for protecting the environment and complying with current laws. To do this, there are many service areas spread across France and Europe.
These specially designed spaces allow easy drainage of grey water, often using a drain valve connected to a proper evacuation system.
You will find them at :

• municipal service areas, free or paid
• campsites
• motorway service stations
• certain large stores with dedicated motorhome spaces

Apps such as Park4Night or Campercontact can greatly help you locate these service areas during your travels. They allow you to plan your stops and avoid uncomfortable situations.
Be careful, discharging wastewater into nature or on public roads is prohibited and can result in fines (up to €1,500 in France).
This not only harms the environment but also tarnishes the image of freedom travel. Respecting these rules helps make the adventure enjoyable for everyone.

The vehicles offered by AVIS explore are all designed for simple and clean drainage thanks to modern and practical systems, ensuring you a worry-free road trip.

How to drain grey water from a motorhome step by step

Draining grey water is a simple operation, but it requires a bit of method to do it cleanly and efficiently. Here’s how to proceed with complete peace of mind.

Step 1 : Prepare the necessary equipment

First of all, make sure you have the following items ready:

• A hose suitable for the drain valve, if needed.
• Gloves for hygiene purposes.
• Access to a service area dedicated to motorhomes.

Step 2 : Position the vehicle correctly

Park precisely above or near the grate designed for grey water drainage. Some service areas are equipped with a special zone where water can be directly evacuated.

Step 3 : Open the drain valve

Locate the valve under the vehicle and open it gently to let the wastewater flow out. If your motorhome is equipped with a hose, connect it to guide the water towards the drain.

Step 4 : Monitor the flow

Allow the tank to empty completely, this generally takes a few minutes. Take this opportunity to visually check the state of the water : very dirty or smelly water may indicate that the tank needs cleaning.

Step 5 : Close the valve and clean the equipment

Once the drainage is complete, carefully close the valve. Quickly rinse the hose and gloves if you used them. Respecting the cleanliness of the area is essential for the comfort of future travelers.

Bonus tips !

• In winter, watch out for freezing: a full grey water tank could freeze and damage the system. Drain more frequently during cold periods.
• Use specific products to prevent bad odors and maintain the proper functioning of the tank.

With AVIS explore, all our motorhomes are designed to make this operation as easy as possible.
Our teams will explain everything in detail when you take charge of your vehicle.

5 tips to maintain the grey water tank

Regular maintenance of your motorhome’s grey water tank is essential to ensure good hygiene on board and maintain comfort throughout your journey.

1. Use suitable products

To reduce unpleasant odors and prevent clogging, it is recommended to use specific products designed for grey water treatment.
These solutions, often biodegradable, prevent deposit formation and make drainage easier.

1. Drain frequently

Never let water stagnate too long in the tank, heat can accelerate the growth of bacteria responsible for bad smells. By draining regularly (every 2 to 3 days on average), you can avoid this issue.

1. Maintain the drain valve

The drain valve is a crucial component for easily evacuating wastewater.
Ensure it always works properly.
Regular cleaning and frequent opening/closing help prevent blockages.

1. Check the tank’s watertightness

Regular visual inspections help ensure there are no cracks or leaks. A damaged tank could not only affect your comfort but also expose you to fines in case of leaks on public roads.

1. Choose your water carefully to limit deposits

Hard water can eventually clog pipes and the grey water tank. Using filtered water when possible can extend the lifespan of your system.

With these simple and effective actions, maintaining your grey water system becomes an easy routine to integrate into your travels. At AVIS explore, we provide all the practical advice you need during vehicle handover so you can hit the road with peace of mind.

I RENT MY MOTORHOME !

FAQ

What is grey water and how is it different from black water ?

Grey water comes from the sinks, washbasins, and showers of the motorhome, while black water comes from the toilets. Both types of water require specific drainage to protect the environment and maintain hygiene on board.

Can I drain my motorhome anywhere ?

No, drainage must be carried out exclusively at designated service areas. Discharging wastewater into nature is prohibited and can result in a fine of up to €1,500 in France.

What should I do if the drain valve is blocked ?

If the drain valve is blocked, do not force it. Gently clean the area with warm water if possible and quickly contact specialized assistance, such as the service offered by AVIS explore, to avoid damaging your system.

How can I prevent bad odors in the grey water tank ?

To avoid bad smells, drain the tank regularly, use biodegradable products specifically designed for grey water treatment, and rinse the tank after each complete drainage.