Research carried out by academic institutions into the causes and effects of transient surge, along with analysis of asset failures by water companies, has revealed that over 50% of unplanned supply interruptions can be traced back to network activity nearby, primarily valve operations, that has taken place within the preceding seven days.
Working in collaboration with Sheffield University and Severn Trent Water, Morrison Utility Services is spearheading a new ‘Calm Networks‘ approach to valve operations. Our purpose-built Calm Networks training rig is designed to demonstrate the potential pressure surge consequences of operating distribution network valves and how these damaging transient surges can be avoided or reduced by modifying traditional operational practices.
Yorkshire Water, Thames Water and Anglian Water have all engaged Morrison Utility Services to design, supply and install a Calm Networks training rig and provide bespoke training to almost 500 valve operator employees to raise their awareness and understanding of how to avoid transient pressure surges.
The rig consists of a closed loop of approximately 200m of 90mm diameter PE pipe fed by a heavy duty pump from a tank reservoir. Simulating a section of operational main, the rig can be adjusted to produce a varied range of flow velocities and pressures. The system is equipped with various valves, hydrants, PRV, MSM chamber and other apparatus to replicate equivalent network installations, configurations and conditions.
Strategically positioned pressure sensors, capable of measuring pressure variations and pulses as short as 5/1000ths of a second, are connected (via laptop) to a large display, enabling real time graphical display of pressure variations to demonstrate to trainees the pressure consequences of the operation of the various valves and other apparatus.
By promoting the Calm Networks approach, our aim is to raise awareness of the importance of modifying operational practice to support the ongoing drive to deliver strong customer service and improved SIM performance. Our work is proving successful and evidence is already pointing to a reduction in the number of burst mains and unplanned customer supply interruptions.