| No. | Common performance commitment for PR19 | Link to latest definition | Status of the definition |
| 1 | Customer measure of experience (C-MeX) | Delivering Water 2020: Our final methodology for the 2019 price review. Appendix 3: Customer measure of experience (C-MeX) and developer services measure of experience (D-MeX) | The definition of C-MeX will continue to be developed through working groups and a pilot. |
| 2 | Developer services measure of experience (D-MeX) | Delivering Water 2020: Our final methodology for the 2019 price review. Appendix 3: Customer measure of experience (C-MeX) and developer services measure of experience (D-MeX) | The definition of D-MeX will continue to be developed through working groups and a pilot. |
| 3 | Water quality compliance
The DWI’s Compliance Risk Index (CRI) |
DWI Compliance Risk Index (CRI) definition | Final definition for PR19. |
| 4 | Water supply interruptions
Average supply interruption greater than three hours (minutes per property) |
Reporting guidance – supply interruptions | Final reporting guidance for PR19.
This is the same guidance as included in the March 2018 report for Ofwat and Water UK: “Targeted review of common performance commitments”. |
| 5 | Leakage
Leakage in megalitres per day (Ml/d), three-year average |
Reporting guidance – leakage | Final reporting guidance for PR19.
This is the same guidance as included in the March 2018 report for Ofwat and Water UK: “Targeted review of common performance commitments” modified to clarify which definition to use as the common performance commitment for PR19. |
| 6 | Per capita consumption (PCC)
Average amount of water used by each person that lives in a household property (litres per head per day) |
Reporting guidance – per capita consumption | Final reporting guidance for PR19.
This is the same guidance as included in the March 2018 report for Ofwat and Water UK: “Targeted review of common performance commitments”. |
| 7 | Internal sewer flooding
The number of internal flooding incidents per year (sewerage companies only) |
Reporting guidance – sewer flooding | Final reporting guidance for PR19.
This is the same guidance as included in the March 2018 report for Ofwat and Water UK: “Targeted review of common performance commitments”. |
| 8 | Pollution incidents
Category 1 – 3 pollution incidents per 10,000km of sewerage network, as reported to the Environment Agency and Natural Resources Wales (sewerage companies only) |
Environment Agency Environmental performance Assessment (EPA) methodology – v8
Environment Agency Environmental performance Assessment (EPA) methodology – v9 Incidents and their classifications: Common Incident Classification Scheme (CICS) Natural Resources Wales – Incident Categorisation
|
At the time of the PR19 final determination the definition referenced version 3 of the EPA methodology. Effective from 01 April 2021 the reference in the definition was updated to version 8 for companies operating mainly in Wales and version 9 for companies operating mainly in England. |
| 9 | Risk of severe restrictions in a drought
Percentage of the population the company serves that would experience severe supply restrictions (for example, standpipes or rota cuts) in a 1 in 200 year drought |
Drought resilience metric |
Revised definition issued on 13 March 2018 following feedback from stakeholders. The overall measure will be reported as the percentage of the population the company serves that would experience severe supply restrictions (for example, standpipes or rota cuts) in a 1-in-200 year drought. |
| 10 | Risk of sewer flooding in a storm (new risk-based resilience metric – wastewater)
Percentage of population at risk of sewer flooding in a 1-in-50 year storm (medium and high risk properties). |
Reporting guidance – risk of sewer flooding in a storm Developing and trialling wastewater resilience metrics (Atkins)
|
Final definition for PR19. |
| 11 | Mains bursts (asset health metric 1 – water) | Reporting guidance – mains repairs per 1,000km | Final reporting guidance for PR19.
This is the same guidance as included in the March 2018 report for Ofwat and Water UK: “Targeted review of common performance commitments”. |
| 12 | Unplanned outage (asset health metric 2 – water)
Unplanned outage is a temporary loss of maximum production capacity |
Reporting guidance – unplanned outage
|
Final reporting guidance for PR19.
We have made some changes to the guidance as included in the March 2018 report for Ofwat and Water UK: “Targeted review of common performance commitments”. These were to clarify that the metric relates to unplanned outage, not all outage and the metric relates to peak week production capacity, not dry year peak week production capacity. |
| 13 | Sewer collapses (asset health metric 3 – wastewater) (sewerage companies only) | Reporting guidance – sewer collapses per 1,000km | Final reporting guidance for PR19.
This is the same guidance as included in the March 2018 report for Ofwat and Water UK: “Targeted review of common performance commitments”. |
| 14 | Treatment works compliance (asset health metric 4 – wastewater) (sewerage companies only) |
Environment Agency Environmental performance Assessment (EPA) methodology – v8 Environment Agency Environmental performance Assessment (EPA) methodology – v9
|
At the time of the PR19 final determination the definition referenced version 3 of the EPA methodology. Effective from 01 April 2021 the reference in the definition was updated to version 8 for companies operating mainly in Wales and version 9 for companies operating mainly in England. |
The reporting guidance for seven of the common performance commitments (water supply interruptions, leakage, per capita consumption, internal sewer flooding, mains bursts, unplanned outage and sewer collapses) was developed through a targeted review. The final version of the targeted review report is available here.
| Type | Asset health performance commitment for PR19 | Link to latest definition | Status of the definition |
| W | Event Risk Index (ERI) | DWI Event Risk Index (ERI): Definition | Final definition for PR19. |
| W | Properties at risk of receiving low pressure | Properties at risk of receiving low pressure | Final definition for PR19. |
| W | Customer contacts about water quality (appearance) | DWI information letter | Definition as in DWI information letter 1/2006 dated 6 January 2006. |
| W | Customer contacts about water quality (taste and odour) | DWI information letter | Definition as in DWI information letter 1/2006 dated 6 January 2006. |
| W | Compliance Risk Index (CRI) – water treatment works (sub category of CRI) | DWI Compliance Risk Index (CRI) definition | Final definition for PR19. |
| W | CRI – supply points (sub category of CRI) | DWI Compliance Risk Index (CRI) definition | Final definition for PR19. |
| W | CRI – service reservoirs (sub category of CRI) | DWI Compliance Risk Index (CRI) definition | Final definition for PR19. |
| W | CRI – water supply zones (sub category of CRI) |
DWI Compliance Risk Index (CRI) definition
|
Final definition for PR19. |
| W | Unplanned maintenance – non-infrastructure (water) | Unplanned non-infrastructure maintenance | Final definition for PR19. |
| WW | Sewer blockages | Sewer blockages | Final definition for PR19. |
| WW | External sewer flooding | Reporting guidance – sewer flooding | Final reporting guidance for PR19.
This is the same guidance as included in the March 2018 report for Ofwat and Water UK: “Targeted review of common performance commitments” modified to clarify which definition of external sewer flooding is the standard definition for PR19. |
| WW | Sewage treatment works compliance
Percentage of population equivalent, served by sewage treatment works with numeric limits, which were non-compliant with: sanitary look-up table limits or nutrient limits, urban wastewater treatment directive (UWWTD) look-up table limits or nutrient limits |
Sewage treatments works compliance
|
Final definition for PR19. |
| WW | Unplanned maintenance – non-infrastructure (wastewater) | Unplanned maintenance – non-infrastructure | Final definition for PR19. |