Supply interruptions - performance commitment data
What are performance commitments (PCs)?
The water regulator Ofwat sets targets called performance commitments (PCs) to ensure companies deliver the best possible service for customers, society and the environment. Wessex Water has a range of PCs for the 2020-25 period.
Each year we report our results against these commitments, in our Annual Performance Report.
Where appropriate we’re publishing the data underpinning calculation of the PCs – you can find our other PC datasets in the Performance Commitments section.
Water supply interruptions PC
Every day we treat and supply more than 273 million litres of drinking water to 1.4 million customers. Our supply grid allows us to move water around to meet demand across our region, ensuring our customers have a more reliable supply.
Managing our network in this way, we endeavour to maintain continuous supplies to customers, however this is not always possible. Interruptions can occur for a variety of reasons such as planned maintenance work, a burst water main or third-party damage to our network.
The water supply interruptions PC reports the number of minutes lost on average per customer, for interruptions of three hours or more.
This measure acts as an indicator of the resilience of our water supply network and how well we can recover from an incident, thereby incentivising good stewardship and management of the network.
Dataset details
The dataset provides details of the supply interruptions contributing to our performance commitment, as per Ofwat’s detailed reporting guidance. In short, this means all planned and unplanned supply interruptions lasting three hours or more.
This includes interruptions affecting non-household properties (e.g. businesses) and interruptions resulting from the actions of third parties.
Properties that are unoccupied are still included in the property count for each interruption.
Properties affected by multiple interruptions in a reporting year are included once for each interruption.
|
Column position |
Column heading |
Description |
Units |
|
1 |
APR reporting year |
The reporting year that this interruption contributes towards, e.g. 2020-2021, 2021-2022. |
N/A |
|
2 |
Interruption category |
The scale of interruption. There are two possible entries: ‘No water’ indicates a small incident involving one or a small number of properties. ‘Supply interruptions’ indicates a network interruption affecting multiple properties simultaneously. |
N/A |
|
3 |
Location |
The village or town where the interruption took place. For reasons of anonymisation, a more exact location is not provided. |
N/A |
|
4 |
Interruption type |
Whether the interruption is scheduled or not. There are four possible entries: ‘Planned’ – An interruption that we schedule in advance for us to carry out specific work on the network e.g. maintenance or repair. ‘Planned/Overrun’ – An interruption that we schedule in advance and anticipate will last under three hours, but exceeds that. ‘Unplanned’ – An interruption that was not scheduled in advance e.g. an interruption resulting from a water main burst. ‘Third party’ – An interruption resulting from actions outside of Wessex Water’s control e.g. damage to our network by another utility company. |
N/A |
|
5 |
Properties interrupted |
The number of properties that lost water during the interruption. |
number |
|
6 |
Interruption start |
The date and time that properties began to lose water supply, e.g. 10/10/2020 08:08. This is determined from pressure monitoring at the water main, customer contacts about loss of water, or modelling. |
dd/mm/yyyy hh:mm |
| 7 | End of interruption |
The date and time that all previously affected properties regained water supply, e.g. 10/10/2020 13:12. This is determined from pressure monitoring at the water main or contact with affected customers. |
dd/mm/yyyy hh:mm |
|
8 |
Interruption period (DD:HH:MM) |
The duration of the supply interruption in hours and minutes. This is the difference between the start and end of the interruption in column positions 6 and 7. |
dd:hh:mm |
|
9 |
Interruption minutes (>= 3 hours) |
The duration of the supply interruption in minutes. The minimum value in this column is 180 because the PC only includes water supply interruptions of three hours or more. |
minutes |
|
10 |
Reason for interruption |
For planned interruptions, there are seven possible entries: ‘Burst main’ – Rupture of a water main and subsequent work to repair it. ‘Mains rehabilitation’ – Work to improve the condition of existing water mains. ‘Mains replacement’ – Work to lay a new water main in the place of an existing one. ‘New mains’ – Work to lay a water main where there hasn't been one previously. ‘Not recorded’ ‘Planned leaks’ – Work to repair a leak. ‘Pressure Reducing Valve issue’ – Work to resolve a problem with a Pressure Reducing Valve (PRV) in our network. All interruptions assigned the type ‘Planned / overrun’ in column 4 give a reason of ‘Planned / overrun’ in this column. For unplanned interruptions, there are seven possible entries: ‘Air lock’ – Occasionally air can get trapped within the pipe network and this can result in the loss of supplies. ‘Booster failure’ – Failure of a booster pump that results in a failure to supply. ‘Burst main’ – Rupture of a water main and subsequent work to repair it. ‘Customer responsibility’ – Failure of customer owned pipework and / or internal plumbing ‘Maintenance / repair’ – Any other interruption which doesn’t fit into one of these categories. ‘Not recorded’ ‘Pressure Reducing Valve issue’ – Work to resolve a problem with a Pressure Reducing Valve (PRV) in our network. All interruptions assigned the type ‘Third party’ in column 4 give a reason of ‘Third party’ in this column. |
N/A |
How was this data collated?
All supply interruptions information is collated in dedicated online corporate systems. To compile our annual reporting to Ofwat, we extract the details of the relevant interruptions into Excel. The published data set is an extract of this, with simplified location information.
Data quality
In some cases we cannot give an individual start time and end time as the event was made up of a number of interruption areas with different start and end times. These entries are recorded as “n/a”.
Publish frequency
For the remaining years of the 2020-25 period, an additional year of data will be added after the annual reporting period.
Contact
If you have any questions or comments about this data set, please get in touch via opendata@wessexwater.co.uk
Terms of use
This dataset is licensed under CC BY, an open data licence, to make it freely available to other potential customers, stakeholders or interested organisations.
Supplementary information
You may also be interested in Discover Water’s summary data from across the industry: DiscoverWater (en-GB)
Our supply grid allows us to move water around to meet demand across our region, but interruptions can still occur, for example if third parties damage our network or if a water main bursts. One of our ‘performance commitments’ (targets) aims to minimise the number of minutes lost on average per customer, for interruptions of three hours or more.
About this dataset
| Last updated |
1 week ago
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| Commitments |
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