Cresset & Weir Cresset Distributors

Ham Baker Cresset distributor column is a proven and reliable design that has been used the waste water industry for well over 60 years. Low maintenance design that uses an air lock seals arrangement that lasts the lifetime of the column. No rubber seal to replace.


Feed Arrangement Siphon or Gravity
Filter bed diameter range 10m to 40m
Flow Range 5 l/s to 150 l/s
Top Bearing design Thrust bearing
Column Sizes 100mm to 450mm
Asset life 25 years plus
Arm Size  50mm to 200mm
Ambient air temperature -10 to +40 degree C
Materials Mild steel & Cast iron
Drive arrangement External mounted


  • Suitable for beds up to 40m diameter
  • Flows from 5 to 150 l/s
  • Cast iron centre column, crosshead and duckfoot base for maximum lift
  • ‘Airlock’ Tanks which create an almost frictionless seal which requires a low driving head.
  • Reduced wear and extended working life, in excess of 50 years
  • Drive and overflow (Weir Cresset) arms to give curtain flow with spreader plates (jet reaction) or top centre nozzles (powered drive)

The Airlock Seal is almost frictionless and makes the machine ideal for installation in very low hydraulic head situations whilst still maintaining the ability to achieve jet reaction.

The Weir Cresset is simply an extension to the Standard Cresset, which gives the option of a very efficient flow split through the machine, to give optimum distribution at minimum and maximum flows.

The “Weir Cresset” Distributor is similar in construction to the Cresset Distributor except that inside the revolving inner tank there are weir plates to stop the flow reaching the two overflow arms. The initial flow passes directly to the two drive arms and as the flow increases it passes to the two overflow arms over the weir, as shown above. The two overflow arms are usually larger than the two drive arms in order to give as large a volume variation as possible.

Whilst recirculation is often used to maintain a constant flow through a sewage works and obviating the need for syphons, it is often found that the flow is not constant to use standard Distributors and the additional flexibility of the “Weir Cresset” is most useful

The design of the “Weir Cresset” provides a long weir length which enables this type of distributor to pass a large increase in volume with very little increase in head.