2019-20 League Tables

These tables take trading parties and arranges them based on their performance against the Market and Operational Performance Standards (MPS and OPS). To make the data more meaningful, you will see that we have segmented trading parties into five groups and have used a clear colour-coding to indicate who sits in the upper and lower quartiles of trading party performance.


To note:

  • The performance trend indicator shows change greater than +/-2% between April 2019 and March 2020. Charges are shown as invoiced (between April 2019 and February 2020. March 2020 was not invoiced due to COVID-19)
  • After undertaking a substantial data migration, Wave saw a dip in their levels in October 2019 when entering in circa 30,000 meter readings that had earlier been rejected by CMOS due to a known issue that had not been rectified. Had this error not occurred, their estimated performance at the end of the Financial Year would have been around 83.37% putting them in 5th place
  • As of October 2019, Business Stream and Yorkshire Water Services merged into one entity. Yorkshire were at the top of the table for the half year results which is why the 1st position is not shown in rankings for April-Sept 2019 in the table above.


To note:

  • Yu Water and Pod53 have been excluded due to a low task volume
  • Tor Water ceased to trade in February 2020.


To note:

  • Albion, Waterscan and Coca-Cola have been excluded due to low task volume.


To note:

  • SSE, Hafren Dyfrdwy, Icosa, Severn Trent Services, Dwr Cymru Welsh Water and Veolia have been excluded due to low task volume.



To note:

  • Unlike MPS, all OPS data is self-reported and is not sourced through CMOS

  • Trade effluent sampling tasks, G4a and G4b, have been excluded from the ‘Total tasks completed’ column due to their high volumes
  • Dwr Cymru Welsh Water have been excluded due to low task volume; however it should be noted that they continue to achieve 100% task success since May 2018.


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