top of page


Wheeler Bottom Underdrain

Retroliner™ is an ideal choice for Wheeler Bottom Underdrain rehabilitations. Retroliner™ inserts eliminates the typical wear and tear caused by the rotation of porcelain distribution spheres; while still maintaining the integrity and performance of the Wheeler Bottom Underdrain.

Rettroliner 1.jpg

Construct and Rehabilitate

With over 75 years of experience in the construction and rehabilitation of Monolithic and Precast Wheeler Bottoms, Roberts' construction crews install and rehab thousands of square feet of underdrains each year.

Retroliner installation 02.jpg

Color-Coded Retroliners Balance Flow

Traditional Wheeler Bottom Underdrains are made with uniform hoppers, thimbles, and porcelain spheres. This design doesn’t account for unequal flow created by support piers, flume geometry and size, and hydraulic losses.


Traditional liners are uniform and will not adjust flow throughout the filter. Flow is typically lower in corners and in and around piers resulting in filter maldistribution.

Retroliner - Low Flow Zone.jpg

With the help of structural evaluation, in-field measurements, and computational fluid dynamics (CFD) Roberts can use color-coded Retroliner™'s to balance flow and improve filter performance. The Retroliner™ has different flow characteristics that allow filters to be rebalanced for even distribution.

color coded 3.jpg
transparent logo.png

Questions about Retroliner?

Thanks for submitting!

website header.png
bottom of page