Research and analysis

Northumbrian Water EPA data report 2020

Updated 14 January 2022

Applies to England

This report provides company specific data and information on the Environmental Performance Assessment (EPA) metrics. It contains current year and historic performance data. For further information on what each EPA metric means see our EPA metric guide.

In addition to the EPA metrics this report contains a section on event duration monitoring (EDM) delivery. For a comparison between water companies and wider regulatory information see the Environmental performance of the water and sewerage companies in 2020 report.

We set targets for each EPA metric. Company performance is then given a red, amber or green (RAG) status:

  • red - performance significantly below target
  • amber - performance close to or slightly below target
  • green - performance better than target

The thresholds are reviewed every 5 years.

1. EPA performance star rating

Annual performance star rating after assessment of Northumbrian Water’s performance across all EPA metrics

Year Overall EPA star rating (out of 4) Star rating description
2011 2 stars Below average company
2012 3 stars Above average company
2013 3 stars Above average company
2014 3 stars Above average company
2015 3 stars Above average company
2016 2 stars Company requires improvement
2017 2 stars Company requires improvement
2018 4 stars Industry leading company
2019 2 stars Company requires improvement
2020 4 stars Industry leading company

2. Total pollution incidents (sewerage) metric (category 1 to 3)

Main facts

For 2020:

  • 43 actual incidents
  • 76% fewer incidents per 10,000km sewer than in 2011
  • 29,848km sewer length

Annual number of pollution incidents (category 1 to 3) from Northumbrian Water sewerage assets, with EPA rating

2011 to 2015 data

Year 2011 2012 2013 2014 2015
EPA status amber amber amber amber amber
Incidents per 10,000km sewer 59 120 79 54 97
Actual incident numbers 94 192 127 87 156

2016 to 2020 data

Year 2016 2017 2018 2019 2020
EPA status amber green green green green
Incidents per 10,000km sewer 38 17 12 15 14
Actual incident numbers 111 50 37 46 43

Annual number of pollution incidents (category 1 to 3) from Northumbrian Water sewerage assets, also showing EPA status and thresholds

Graph note: the thresholds for a RAG status are shown in the graph background. EPA thresholds for normalised incidents (per 10,000km sewer) are shown in the EPA metric guide. They are revised every 5 years. Sewer length data was collected in 2011, then reviewed and adjusted where necessary in following years. Sewer length affects the actual number of incidents required to fall within a particular RAG status:

  • green status for Northumbrian Water was equivalent to 81 or fewer actual incidents in 2011 to 2015, 75 or fewer in 2016 and 76 or fewer in 2017 to 2020
  • red status for Northumbrian Water was equivalent to 208 or more actual incidents in 2011 to 2015, 146 or more in 2016 and 148 or more in 2017 to 2020

Number of pollution incidents (category 1 to 3) from Northumbrian Water sewerage and clean water supply assets in 2020

Asset type Number of pollution incidents (category 1 to 3)
Combined sewer overflow 6
Foul sewer 17
Other water industry premises 0
Pumping station 12
Rising main 0
Sewage treatment works 8
Storm tank 0
Surface water outfall 0
Water distribution system (clean)* 18
Water treatment works (clean)* 1

* Water distribution system (clean water supply) and water treatment works (clean water supply) are not part of the EPA total pollution incident (sewerage) metric.

For sewerage pollution incidents (category 1 to 3) all water companies should achieve green EPA status (for 2020 equivalent to 25 or fewer incidents per 10,000km sewer).

For 2020:

  • 14 sewerage pollution incidents per 10,000km of sewer - this is rated as green
  • performance was better than the sector average (33) for sewerage pollution incidents per 10,000km of sewer
  • best performing company for sewerage pollution incidents

3. Serious pollution incidents (sewerage) metric (category 1 and 2)

Main facts

For 2020:

  • 1 actual serious incident
  • 96% fewer serious incidents per 10,000km sewer than in 2011

Annual number of serious pollution incidents (category 1 and 2) from Northumbrian Water sewerage assets, with EPA rating

2011 to 2015 data

Year 2011 2012 2013 2014 2015
EPA status red amber amber amber amber
Serious incidents per 10,000km sewer 6.8 1.9 3.1 1.9 3.1
Actual serious incident numbers 11 3 5 3 5

2016 to 2020 data

Year 2016 2017 2018 2019 2020
EPA status red amber green amber green
Serious incidents per 10,000km sewer 3.1 0.7 0.3 0.7 0.3
Actual serious incident numbers 9 2 1 2 1

Annual number of serious pollution incidents (category 1 and 2) from Northumbrian Water sewerage assets, also showing EPA status and thresholds

Graph note: the thresholds for a RAG status are shown in the graph background. EPA thresholds for normalised incidents (per 10,000km sewer) are shown in the EPA metric guide. They are revised every 5 years. Sewer length data was collected in 2011, then reviewed and adjusted where necessary in following years. Sewer length affects the actual number of serious incidents required to fall within a particular RAG status:

  • green status for Northumbrian Water was equivalent to 2 or fewer actual serious incidents in 2011 to 2015 and 1 or fewer in 2016 to 2020
  • red status for Northumbrian Water was equivalent to 7 or more actual serious incidents in 2011 to 2015 and 5 or more in 2016 to 2020

Number of serious pollution incidents (category 1 and 2) from Northumbrian Water sewerage and clean water supply assets in 2020

Asset type Number of serious pollution incidents (category 1 and 2)
Combined sewer overflow 0
Foul sewer 0
Other water industry premises 0
Pumping station 0
Rising main 0
Sewage treatment works 1
Storm tank 0
Surface water outfall 0
Water distribution system (clean)* 3
Water treatment works (clean)* 0

* Water distribution system (clean) and water treatment works (clean) are not part of the EPA serious pollution incident (sewerage) metric.

For serious sewerage pollution incidents (category 1 and 2) all water companies should achieve green EPA status (for 2020 equivalent to 0.5 or fewer serious incidents per 10,000km sewer).

For 2020:

  • 0.3 serious sewerage pollution incidents per 10,000km of sewer - this is rated as green
  • performance was better than the sector average (0.7) for serious sewerage pollution incidents per 10,000km of sewer

4. Discharge permit compliance metric (numeric)

Main facts

For 2020:

  • 160 permitted sewage treatment works (STW)
  • 17 permitted water treatment works (WTW)

Annual discharge permit compliance (numeric) for Northumbrian Water (STW and from 2016 includes WTW), with EPA rating

2011 to 2015 data

Year 2011 2012 2013 2014 2015
EPA status green green amber green green
Percentage permit compliance 99.4 100 98.1 99.4 99.4
Number of permitted STW 158 158 159 159 159
Number of non-compliant STW 1 0 3 1 1

2016 to 2020 data

Year 2016 2017 2018 2019 2020
EPA status amber red green red green
Percentage permit compliance 97.8 96.0 99.4 96.6 99.4
Number of permitted STW 158 158 159 160 160
Number of permitted WTW 22 15 14 16 17
Number of non-compliant STW 1 2 0 5 1
Number of non-compliant WTW 3 5 1 1 0

Note: 3 of the non-compliant STW in 2019 were due to sample shortfalls associated with laboratory analysis not meeting quality control standards, and are not associated with any known environmental impact.

Annual discharge permit compliance (numeric) for Northumbrian Water (STW and from 2016 includes WTW), also showing EPA status and thresholds

Graph note: the thresholds for a RAG status are shown in the graph background and in the EPA metric guide. They are revised every 5 years.

For discharge permit compliance (numeric) all water companies should achieve green EPA status (for 2020 equivalent to compliance at 99% or more of sites).

For 2020:

  • 99.4% numeric discharge permit compliance - this is rated as green
  • 99.4% numeric discharge permit compliance at STW and 100% numeric discharge permit compliance at WTW
  • performance was better than the sector average (99.2%) for numeric discharge permit compliance

5. Self-reporting of pollution incidents metric

Main facts

For 2020:

  • 81% incidents self-reported
  • 50 incidents self-reported
  • 12 incidents reported by others

Annual self-reporting of pollution incidents (category 1 to 3) from Northumbrian Water sewerage and clean water supply assets, with EPA rating

2011 to 2015 data

Year 2011 2012 2013 2014 2015
EPA status red green amber amber green
Percentage of incidents self-reported 30 71 39 56 82
Number of incidents self-reported 28 138 50 50 131

2016 to 2020 data

Year 2016 2017 2018 2019 2020
EPA status amber green green green green
Percentage of incidents self-reported 68 80 84 80 81
Number of incidents self-reported 75 47 51 53 50

Annual self-reporting of pollution incidents (category 1 to 3) from Northumbrian Water sewerage and clean water supply assets, also showing EPA status and thresholds

Graph note: the thresholds for a RAG status are shown in the graph background and in the EPA metric guide. They are revised every 5 years.

Self-reporting of pollution incidents (category 1 to 3) from Northumbrian Water sewerage and clean water supply assets in 2020

Asset type Number of pollution incidents self-reported (category 1 to 3) Number of pollution incidents not self-reported (category 1 to 3)
Combined sewer overflow 6 0
Foul sewer 12 5
Other water industry premises 0 0
Pumping station 12 0
Rising main 0 0
Sewage treatment works 4 4
Storm tank 0 0
Surface water outfall 0 0
Water distribution system (clean) 15 3
Water treatment works (clean) 1 0

Self-reporting of serious pollution incidents (category 1 and 2) from Northumbrian Water sewerage and clean water supply assets in 2020

Asset type Number of pollution incidents self-reported (category 1 and 2) Number of pollution incidents not self-reported (category 1 and 2)
Combined sewer overflow 0 0
Foul sewer 0 0
Other water industry premises 0 0
Pumping station 0 0
Rising main 0 0
Sewage treatment works 0 1
Storm tank 0 0
Surface water outfall 0 0
Water distribution system (clean) 2 1
Water treatment works (clean) 0 0

For self-reporting of pollution incidents all water companies should achieve green EPA status (for 2020 equivalent to 75% or more of their incidents being self-reported).

For 2020:

  • 81% self-reporting of pollution incidents - this is rated as green
  • performance was better than the sector average (77%) for self-reporting of pollution incidents

6. National Environment Programme (NEP) delivery metric

Main facts

For the financial year ending 2021:

  • 5 Water Industry NEP (WINEP) schemes were completed to the planned deadline
  • 0 schemes were not completed to the planned deadline

Annual delivery of the NEP (WINEP from April 2020) by Northumbrian Water, with EPA rating

Data for financial years ending 2012 to 2016

Financial year ending 2012 2013 2014 2015 2016
Asset Management Plan (AMP) AMP5 AMP5 AMP5 AMP5 AMP6
EPA status green green green green green
Percentage of NEP complete to date (cumulative) 110 100 100 100 100
Cumulative number of schemes completed during AMP period 11 13 14 24 8

Data for financial years ending 2017 to 2021

Financial year ending 2017 2018 2019 2020 2021
Asset Management Plan (AMP) AMP6 AMP6 AMP6 AMP6 AMP7
EPA status green green green green green
Percentage of NEP complete to date (cumulative) 100 100 100 100 100
Cumulative number of schemes completed during AMP period 21 42 50 73 5

Table note: AMP5 schemes that were completed early before their planned year were included in the cumulative delivery percentage (in some cases resulting in percentages over 100%). AMP6 schemes that were completed early before their planned year were not included in the cumulative delivery percentage until their planned year (cannot report over 100%). The thresholds for each RAG status are in the EPA metric guide. They are revised every 5 years.

For NEP delivery all water companies should achieve green EPA status (for the financial year ending 2021 equivalent to 99% or more of the WINEP being delivered on time).

For the financial year ending 2021:

  • 100% WINEP delivery - this is rated as green
  • joint best performing company for NEP delivery

7. Sludge disposal and use metric

Main facts

For 2020:

  • 22,937 (tonnes) total volume produced (dry matter)
  • 5,010ha (hectares) land used for spreading
  • 100% of sludge produced was used in agriculture

Annual compliance with sludge disposal and use metric by Northumbrian Water, with EPA ratings

2011 to 2015 data

Year 2011 2012 2013 2014 2015
EPA status green green green green green
Percentage of sludge compliant 100 100 100 100 100

2016 to 2020 data

Year 2016 2017 2018 2019 2020
EPA status green green N/A N/A N/A
Percentage of sludge compliant 100 100 N/A N/A N/A

Table note: from the 2018 calendar year, we suspended the metric from the EPA whilst we reviewed our regulatory regime for sludge. The thresholds for each RAG status are in the EPA metric guide. They are revised every 5 years.

Annual summary of sewage sludge disposal and use (dry matter) by Northumbrian Water

Year Sewage sludge used in agriculture (t thousands) Sewage sludge recovered non-agriculture (t thousands) Sewage sludge disposed (t thousands) Actual quantity produced (t thousands)
2011 47.2 0.6 0.0 47.8
2012 38.9 1.8 0.0 40.7
2013 28.7 2.0 0.0 30.8
2014 25.2 0.0 0.0 25.2
2015 27.7 0.0 0.0 27.7
2016 30.3 0.0 0.0 30.3
2017 26.7 0.0 0.0 26.7
2018 27.7 0.0 0.0 27.7
2019 26.2 0.0 0.0 26.2
2020 22.9 0.0 0.0 22.9

8. Security of Supply Index (SoSI) metric

Main facts

For the financial year ending 2021:

  • 2 water resource zones
  • 700 Ml/d water distributed to the network (megalitres)

Annual compliance with SoSI by Northumbrian Water, with EPA ratings

Financial year ending 2017 2018 2019 2020 2021
EPA status green green green green green
SoSI score 100 100 100 100 100

Table note: the thresholds for each RAG status are in the EPA metric guide.

For SoSI all water companies should achieve green EPA status (for the financial year ending 2021 equivalent to a SoSI of 100).

For the financial year ending 2021:

  • score 100 - this is rated as green

9. Event Duration Monitoring (EDM) delivery

All water companies have investment in place to monitor the vast majority of storm overflows. Installation of EDM monitors is mostly funded through the WINEP however does not form part of the EPA WINEP delivery metric. We have published the EDM dataset from the water companies describing how often and for how long the monitored storm overflows operated during 2020. All water companies have also published their EDM data returns and supporting commentaries.

Northumbrian Water storm overflows

Year 2020
Total number of storm overflows 1,520
Number of storm overflows with annual data reported 1,485
Percentage of storm overflows with annual data reported 98
Average number of spills per storm overflow 22
Average duration of spill (hours) 5