Pollution incidents - performance commitment data

Many of the activities we carry out have the potential to cause pollution to the environment if something goes wrong.

Pollution incidents are assessed regarding their impact on the water environment, the land environment and the air environment, and categorised as one of the following:

• Category 1 - major impact
• Category 2 - significant impact
• Category 3 - minor impact
• Category 4 - no impact

Wessex Water’s pollution incidents performance commitment uses incidents from wastewater (sewage) assets that are classed as category 1-3 impact on water. Category 4 incidents are not included in the metric.  The same categories are used in the Environment Agency’s Water & Sewerage Company Environmental Performance Assessment (EPA).

This data file shows the pollution incident data for Wessex Water for 2020-21 and 2021-22.  The data consists of a National Incident Recording System (NIRS) event no. that acts as a unique ID, information about when and approximately where the incident occurred, and the impact.

You may also be interested in our Pollution Incident Reduction Plan, which summarises the pollution incidents each year (including cause) and sets out our plan for improvements. 

How the data is collated: The data originates from the Environment Agency database that they send us on a monthly basis and then at the end of the year.  To produce the dataset for publishing, unnecessary detail has been removed and we have anonymised location information. Root cause data (in column J) is not Environment Agency data and is not used as part of the EPA. This data is Wessex Water’s understanding of the root cause of the incident and is provided here for context only.

For the remaining years of AMP7, an additional year of data will be added after the annual reporting period. 

If you have any comments or queries about this dataset, please get in touch via marketplace@wessexwater.co.uk