Depending on the characteristics of a rising main, very large positive and negative transient pressures can be generated in the pipe system immediately after a pump stops or a valve closes.

Transient Pressure Tests

Transient surge pressures cause shocks to the pipe system that often result in bursts or sometimes even pipes collapsing due to negative pressures.
When performing pumping station surveys our clients are increasingly requesting that the surveys include measurements of the transient pressures.

We measure the transient pressures in each possible permutation of pump running/ stopped conditions to ensure that we capture the most extreme peak values. Often we repeat the tests several times to confirm consistency of results.

The data we supply provides our clients with a true measurement of the transient surge pressures and enables them to engineer modifications to the system, if necessary, to reduce the damaging peak pressures.

Pipe Blockage Detection

Blockages in rising mains can be very problematic and are often only realised when a pumping station is failing to deliver the required flow rates.  On sewage pumping stations this usually becomes apparent when the sewer starts prematurely spilling to river.

Blockages can be caused by:

• A build up of solids over the length of the pipe
• A build up of solids at a single location
• Air locks

By installing pressure and flow monitoring equipment at accessible locations over the length of the rising main we can help identify the nature of the blockage and its location.