Full retention separators 

Registered white Rewatec logo.

Guard against hydrocarbon pollutants entering the environment with our peace-of-mind full retention separators. 

Rewatec full retention separator
Total protection icon for rewatec bypass separators
Peace of mind

Prevents property contamination. 
Preserves water quality in lakes & rivers. 
Protects public health. 

Commercial solution icon for rewatec bypass separators
Commercial and municipal solutions

Low maintenance costs.  
High quality performance. 
Protects our environment. 


Tailored solution icon for rewatec bypass separators
Tailored solutions

Pre-engineered or bespoke designs. 
Easy to install. 

Built to last icon for rewatec bypass separators
Built to last

Leak-proof design. 
Robust and reliable tanks. 
Durable GRP shells. 

What are full retention separators?

Full retention separators are used where there is a risk of regular oil contamination and a foreseeable risk of significant over spills. They are designed to treat the full flow that can be delivered by a drainage system. This is normally generated by rainfall intensity of 65mm per hour, often referred to as ‘torrential’. 

Example applications 

  • sites with high risk of oil contamination 
  • fuel storage depots 
  • refuelling facilities 
  • vehicle maintenance areas/workshops 
  • where discharge is to a sensitive environment 


Rewatec full retention separator

How do full retention separators work? 

Step 1 

Contaminated water enters the separator where the liquid is retained for a sufficient period to ensure that the pollutants (such as petrol, diesel or oil) separate and rise to the surface of the water. 

Step 2 

The decontaminated water then passes though the coalescing filter before it is safely discharged from the separator, with the remaining pollutants being retained inside the separator. 

Step 3 

Retained pollutants must be emptied from the separator once the level of oil is reached, or the oil level alarm is activated. This waste should be removed from the separator under the terms of the Waste Management Code of Practice. 

Rewatec full retention separator operation


All Rewatec full retention separators have an automatic closure device (ACD) fitted as standard. This is compulsory for all compliant full retention separators and prevents accumulated pollutants flowing through the unit when the maximum storage level is reached. 

Full retention separator maintenance

We have a network of local service partners to maximise the life of your Rewatec full retention separator and to provide years of reliable operation.

We stand by our products 

For over 50 years, we have proudly developed sustainable and long-lasting products that make a real difference for our customers, our professional partners, and, above all, our planet.

Our experience in the industry allows us to give you a complete 20-year warranty for Rewatec full retention separators. 

Rewatec 20 year warranty

Training for professionals

​​​​​​At Premier Tech we provide a full range of training programmes to fully meet the requirements of our professional partners. If you require product functionality guidance or a more detailed training course for installations, we can provide a solution to meet your needs. 

Contact us for more information

Available products

Our Full retention separators are available in a range of sizes to suit all requirements.


Free quote

We are here to help. Request a quote today and our team of experts will be in touch. 

request a quote