Bypass separators

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Protect your property, location and the environment by choosing Rewatec bypass separators, designed specifically for small spillage occurrences or where the risk of a spillage is low. 

Rewatec bypass separator
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Peace of mind

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

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Commercial and municipal solutions

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


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Tailored solutions

Pre-engineered or bespoke designs. 
Easy to install. 

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Built to last

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

What are bypass separators?

Rewatec bypass separators (formally Conder bypass separators) are for use with surface water drainage systems and are designed to prevent hydrocarbons such as diesel, petrol and engine oil from mixing with surface water and entering drainage systems. 

They are used to fully treat all flows generated by rainfall rates of up to 6.5 mm/hr. Separators are used when it is considered an acceptable risk not to provide full treatment for high flows, such as low risk applications.

Example applications 

  • car parks 
  • roadways and major trunk roads 
  • light industrial and goods yards
Rewatec bypass separator


How do bypass separators work?

Pollution prevention is a critical part of sustainable drainage systems and statutory regulations are in force to control the discharge of hydrocarbons such as oil or fuel. 

Rewatec bypass separators have been designed to treat all flow rates up to the designed nominal size. Any flow in excess of the nominal size is allowed to bypass the separation chamber, thereby keeping the separated and trapped oil or fuel safe.

Rewatec bypass separator operation


Step 1 

During the early part of a rain storm, all the contaminated water flow passes through the sediment collection chamber and enters the separation chamber through a patented oil skimming and filter device. 

Step 2 

All the oil then proceeds to the separation chamber where it is separated to the Class 1 standard of 5 mg/L and safely trapped. 

Step 3 

As the rainstorm builds up to its maximum and the level of oil contamination reduces significantly, the nominal size flow continues to pass through the separation chamber and any excess flow of virtually clean water is allowed to bypass directly to the outlet. 

Bypass separator maintenance

A full suite of services is available through Premier Tech’s extensive network of trusted service partners. 

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 bypass separators. 

Rewatec 20 year warranty

Training programmes 

​​​​​​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

We offer a complete range of Rewatec bypass separators to meet your needs. Wherever your site, whatever the regulations.


Free quote

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