MULTIWASH® Filtration Process

MULTIWASH Filtration Process

MULTIWASH® Filtration Process Maximizes Filter Performance

Once you have selected the right type of filtration system for your application, it's equally important to select the most effective filter internals, such as underdrains, washtroughs, and media. WesTech has more options and expertise than anyone else in the market.

One of the leading options for many years now is the MULTIWASH Filtration Process, which combines air and water simultaneously for the duration of the backwash. The combined air and water wash provides a vigorous scouring action to clean the media while specially designed wash trough baffles are used to eliminate media loss.

The superior cleaning performance of the MULTIWASH process prevents both chemical and biological fouling of the filter media, eliminating expensive chemical cleaning or media replacement.

Equip your filters with the MULTIWASH process and get:

  • Guarantees against mudball formation and media loss
  • Consistently better backwash performance
  • The widest available selection of filter media configurations
  • Consistent effluent quality

MULTIWASH Filtration Process was originally developed for wastewater filtration. Deep, large media beds provide longer filter runs while producing comparable effluent quality. Several plant retrofits confirm the powerful backwash provided with the MULTIWASH Filtration Process.

Filter components that support the MULTIWASH Filtration Process include reduced profile underdrains and specially designed washtroughs and collectors.

For more information, visit the following product pages:

Retrofits and Upgrades

Looking to upgrade or retrofit an AERALATER® or existing pressure filter system? Learn more about the MULTIWASH PRO Trough, which makes it easier and quicker to change your existing equipment over to the MULTIWASH system.

You could obtain a reduction in power costs and improved filtration efficiency with MULTIWASH. Contact us to discuss the best options for your plant.


  • Sustained simultaneous air water backwash
  • Guaranteed media cleanliness
  • Guaranteed media loss prevention
  • Adaptable to any media configuration
  • Retrofit options
  • Over 375 installations


  • Cleanest media
  • Consistent effluent quality
  • No mudball formation
  • Proper filter operation
  • Channeling eliminated
  • Best media selected
  • Improved performance for existing filters
  • Proven performance
  • Knowledgeable engineers