Research and analysis

Anglian Water EPA data report 2023

Published 23 July 2024

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 (as published at the time, based on data provided in part by the water companies). For further information on what each EPA metric and performance star ratings mean see our EPA metric guide.

In addition to the EPA metrics, this report contains a section on event duration monitoring (EDM) of storm overflows. For a comparison between water companies and wider regulatory information see the Environmental performance of the water and sewerage companies in 2023 report.

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

  • red – significantly below target
  • amber – below target
  • green – achieved target or better

We review and revise thresholds every 5 years.

1. EPA metric status and performance star rating

Main facts

For 2023:

  • red status for 2 metrics, amber status for 2 metrics and green status for 3 metrics
  • 1 of 5 companies (out of 9) rated as requires improvement (2 stars)

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

Year Overall EPA star rating (out of 4) Star rating description
2011 3 stars Above 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 3 stars Good company
2017 3 stars Good company
2018 3 stars Good company
2019 2 stars Company requires improvement
2020 3 stars Good company
2021 2 stars Company requires improvement
2022 2 stars Company requires improvement
2023 2 stars Company requires improvement

Annual percentage of red, amber or green (RAG) status EPA metric results for Anglian Water

Graph note: there were 6 EPA metrics in the years 2011 to 2015 and 2018 to 2021. There were 7 EPA metrics in the years 2016, 2017, 2022 and 2023.

Annual number of EPA metrics and their RAG status results for Anglian Water

Year Number of metrics in EPA Number of red metrics Number of amber metrics Number of green metrics
2011 6 0 2 4
2012 6 0 4 2
2013 6 0 3 3
2014 6 0 3 3
2015 6 0 4 2
2016 7 0 4 3
2017 7 0 3 4
2018 6 0 3 3
2019 6 1 1 4
2020 6 0 2 4
2021 6 1 2 3
2022 7 1 2 4
2023 7 2 2 3

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

Main facts

For 2023:

  • 40 sewerage pollution incidents per 10,000km of sewer – this is rated as red
  • 307 actual incidents (needed 164 or fewer to be rated as green)
  • 76,437km sewer length
  • performance was worse than the sector (36) for sewerage pollution incidents per 10,000km of sewer
  • 1 of 3 companies (out of 9) to be rated red, no companies rated green

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

2011 to 2015 data

Year 2011 2012 2013 2014 2015
EPA status amber amber amber amber green
Incidents per 10,000km sewer 118 101 89 90 35
Actual incident numbers 518 446 392 394 152

2016 to 2020 data

Year 2016 2017 2018 2019 2020
EPA status amber amber green amber amber
Incidents per 10,000km sewer 32 30 25 35 28
Actual incident numbers 226 228 191 266 210

2021 to 2025 data

Year 2021 2022 2023 2024 2025
EPA status amber amber red no data no data
Incidents per 10,000km sewer 34 33 40 no data no data
Actual incident numbers 258 255 307 no data no data

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

Graph note: the EPA RAG status thresholds are set for normalised (per 10,000km sewer) numbers of sewerage incidents (see our EPA metric guide). We review and revise thresholds every 5 years. Equivalent thresholds for actual incident numbers are calculated using water company sewer length data – these are shown in the graph background and the table below.

EPA thresholds for actual number of Anglian Water sewerage incidents for the calendar years 2011 to 2025

Calendar year Red status Amber status Green status
2011 to 2015 570 or above 223 to 569 222 or below
2016 355 or above 183 to 354 182 or below
2017 to 2020 376 or above 194 to 375 193 or below
2021 318 or above 180 to 317 179 or below
2022 302 or above 172 to 301 171 or below
2023 287 or above 165 to 286 164 or below
2024 279 or above 157 to 278 156 or below
2025 264 or above 150 to 263 149 or below

Number of pollution incidents (total category 1 to 3) from Anglian Water sewerage and water supply assets in 2023

Asset type Number of pollution incidents (category 1 to 3)
Combined sewer overflow 6
Foul sewer 106
Other water industry premises 2
Pumping station 86
Rising main 33
Sewage treatment works 67
Storm tank 1
Surface water outfall 6
Water distribution system (water supply) 26
Water treatment works (water supply) 5

Note: water distribution system and water treatment works (both water supply assets) are not part of the EPA total pollution incidents (sewerage) metric.

Number of pollution incidents (total and breakdown of category 1 to 3) from Anglian Water sewerage and water supply assets in 2023

Asset type Category 1 to 3 Category 1 Category 2 Category 3
Combined sewer overflow 6 0 0 6
Foul sewer 106 0 3 103
Other water industry premises 2 0 0 2
Pumping station 86 0 0 86
Rising main 33 0 2 31
Sewage treatment works 67 0 6 61
Storm tank 1 0 0 1
Surface water outfall 6 0 0 6
Water distribution system (water supply) 26 0 0 26
Water treatment works (water supply) 5 0 0 5

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

Main facts

For 2023:

  • 11 serious incidents – this is rated as red (needed 2 or fewer to be rated as green)
  • 11 serious incidents from sewerage assets
  • 0 serious incidents from water supply assets
  • 1 of 4 companies (out of 9) to be rated red

Annual number of serious pollution incidents (category 1 and 2) from Anglian Water assets (sewerage and from 2021 including water supply), with EPA status

2011 to 2015 data

Year 2011 2012 2013 2014 2015
EPA status amber green amber amber amber
Serious incidents per 10,000km sewer 2 0.7 2.3 1.8 2.3
Actual serious incident numbers – sewerage 9 3 10 8 10

2016 to 2020 data

Year 2016 2017 2018 2019 2020
EPA status amber amber amber red amber
Serious incidents per 10,000km sewer 1.3 1.2 0.8 1.6 1.3
Actual serious incident numbers – sewerage 9 9 6 12 10

2021 to 2025 data

Year 2021 2022 2023 2024 2025
EPA status red red red no data no data
Serious incident numbers – all assets 14 11 11 no data no data
Serious incident numbers – sewerage 14 9 11 no data no data
Serious incident numbers – water supply 0 2 0 no data no data

Annual number of serious pollution incidents (category 1 and 2) from Anglian Water assets (sewerage and from 2021 including water supply), also showing EPA status and thresholds

Graph note: for 2011 to 2020 EPA RAG status thresholds were set for normalised (per 10,000km sewer) numbers of serious sewerage incidents (see our EPA metric guide). Equivalent thresholds for actual serious sewerage incident numbers were calculated using water company sewer length data. We review and revise thresholds every 5 years. For 2021 to 2025 water companies are in one of two groups with different thresholds set for actual serious sewerage and water supply incident numbers. The thresholds for actual serious incident numbers are shown in the graph background and the table below.

EPA thresholds for number of serious incidents from Anglian Water assets (sewerage and from 2021 including water supply) for the calendar years 2011 to 2025

Calendar year Red status Amber status Green status
2011 to 2015 18 or above 7 to 17 6 or below
2016 11 or above 4 to 10 3 or below
2017 to 2020 12 or above 5 to 11 4 or below
2021 and 2022 6 or above 4 or 5 3 or below
2023 and 2024 5 or above 3 or 4 2 or below
2025 4 or above 2 or 3 1 or 0

Number of serious pollution incidents (category 1 and 2) from Anglian Water sewerage and water supply assets in 2023

Asset type Number of serious pollution incidents (category 1 and 2)
Combined sewer overflow 0
Foul sewer 3
Other water industry premises 0
Pumping station 0
Rising main 2
Sewage treatment works 6
Storm tank 0
Surface water outfall 0
Water distribution system (water supply) 0
Water treatment works (water supply) 0

4. Self-reporting of pollution incidents (sewerage and water supply) metric

Main facts

For 2023:

  • 89% of all incidents self-reported, 95% from just pumping stations (PS) and sewage treatment works (STW) combined – this is rated as green
  • 300 self-reported incidents, 38 incidents reported by others
  • performance was better than the sector (84%) for self-reporting of all pollution incidents
  • performance was better than the sector (93%) for self-reporting of just PS and STW pollution incidents combined
  • 1 of 6 companies (out of 9) to be rated green

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

2011 to 2015 data

Year 2011 2012 2013 2014 2015
EPA status amber green green green amber
Percentage of incidents self-reported 64 71 76 76 56
Number of incidents self-reported 335 317 302 311 87

2016 to 2020 data

Year 2016 2017 2018 2019 2020
EPA status amber amber amber amber amber
Percentage of incidents self-reported 66 71 62 71 73
Number of incidents self-reported 155 182 134 208 170

2021 to 2025 data

Year 2021 2022 2023 2024 2025
EPA status amber amber green no data no data
Percentage of incidents self-reported 69 73 89 no data no data
Number of incidents self-reported 193 227 300 no data no data
Percentage of PS and STW incidents self-reported 75 83 95 no data no data
Number of PS and STW incidents self-reported 97 105 145 no data no data

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

Graph note: the EPA RAG status thresholds (for all sewerage and water supply assets) are shown in the graph background and in the EPA metric guide. We review and revise thresholds every 5 years. From 2021 the additional number in brackets is the self-reporting percentage for just PS and STW incidents combined. To achieve green status self-reporting for all assets must be 80% or above and for just STW and PS combined must be 90% or above.

Self-reporting of pollution incidents (category 1 to 3) from Anglian Water sewerage and water supply assets in 2023

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 5 1
Foul sewer 87 19
Other water industry premises 2 0
Pumping station 81 5
Rising main 29 4
Sewage treatment works 64 3
Storm tank 1 0
Surface water outfall 2 4
Water distribution system (water supply) 24 2
Water treatment works (water supply) 5 0

Self-reporting of serious pollution incidents (category 1 to 2) from Anglian Water sewerage and water supply assets in 2023

Asset type Number of serious pollution incidents self-reported (category 1 to 2) Number of serious pollution incidents not self-reported (category 1 to 2)
Combined sewer overflow 0 0
Foul sewer 2 1
Other water industry premises 0 0
Pumping station 0 0
Rising main 2 0
Sewage treatment works 6 0
Storm tank 0 0
Surface water outfall 0 0
Water distribution system (water supply) 0 0
Water treatment works (water supply) 0 0

5. Discharge permit compliance (numeric) metric

Main facts

For 2023:

  • 98.4% numeric discharge permit compliance – this is rated as amber
  • 751 permitted discharge outlets from STW – 98.7% compliance (10 non-compliant STW)
  • 85 permitted discharge outlets from water treatment works (WTW) – 96.5% compliance (3 non-compliant WTW)
  • needed 8 or fewer non-compliant treatment works to be rated as green
  • performance was worse than the sector (98.8%) for numeric discharge permit compliance
  • 1 of 3 companies (out of 9) to not be rated green

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

2011 to 2015 data

Year 2011 2012 2013 2014 2015
EPA status amber amber amber amber green
Percentage permit compliance 97.1 98.1 97.5 98.6 99.0
Number of permitted discharge outlets from STW 721 720 718 719 728
Number of non-compliant STW 21 14 18 10 7

2016 to 2020 data

Year 2016 2017 2018 2019 2020
EPA status green amber amber amber green
Percentage permit compliance 99.1 98.6 98.2 98.6 99.3
Number of permitted discharge outlets from STW 718 718 756 756 756
Number of permitted discharge outlets from WTW 77 75 83 90 92
Number of non-compliant STW 3 8 10 9 3
Number of non-compliant WTW 4 3 5 3 3

2021 to 2025 data

Year 2021 2022 2023 2024 2025
EPA status amber amber amber no data no data
Percentage permit compliance 98.2 98.6 98.4 no data no data
Number of permitted discharge outlets from STW 754 752 751 no data no data
Number of permitted discharge outlets from WTW 89 85 85 no data no data
Number of non-compliant STW 14 10 10 no data no data
Percentage compliance STW 98.1 98.7 98.7 no data no data
Number of non-compliant WTW 1 2 3 no data no data
Percentage compliance WTW 98.9 97.6 96.5 no data no data

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

Graph note: the EPA RAG status thresholds are shown in the graph background and in the EPA metric guide. We review and revise thresholds every 5 years.

6. Delivery of the Water Industry National Environment Programme (WINEP) metric

Main facts

For the financial year ending March 2024 (cumulative progress years 1 to 4 of the WINEP):

  • 99.6% EPA schemes completed within planned deadlines – this is rated as amber (needed 100% to be rated as green)
  • 717 EPA schemes completed within planned deadlines
  • 3 EPA schemes (all water quality) did not meet requirements within planned deadline
  • performance was better than the sector (99.2%)
  • 1 of 3 companies (out of 9) not to be rated green
  • all 892 non-EPA WINEP schemes completed within planned deadlines

Annual delivery of the NEP (WINEP from April 2020) by Anglian 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) 114 103 100 100 100
Cumulative number of schemes completed during AMP period 25 98 97 162 1

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 71 204 209 358 136

Data for financial years ending 2022 to 2026

Financial year ending 2022 2023 2024 2025 2026
Asset Management Plan (AMP) AMP7 AMP7 AMP7 AMP7 AMP8
EPA status green amber amber no data no data
Percentage of WINEP complete within deadlines (to date) 100 99.8 99.6 no data no data
Cumulative number of schemes completed during AMP period 474 587 717 no data no data
Cumulative number of water quality schemes completed during AMP period 324 434 560 no data no data
Cumulative number of water resources schemes completed during AMP period 123 123 125 no data no data
Cumulative number of fisheries, biodiversity and geomorphology schemes completed during AMP period 27 30 32 no data no data

Table note 1: 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 and AMP7 schemes that were completed early before their planned year are not included in the cumulative delivery percentage until their planned year (cannot report over 100%). The EPA RAG status thresholds are in the EPA metric guide. We review and revise thresholds every 5 years.

Table note 2: The WINEP EPA metric data for financial year ending 2023 is different to the EPA metric data published in July 2023. This is as a result of subsequent audits and checking.

7. Sludge disposal and use metric

Main facts

For 2023:

  • 99.43% satisfactory sludge disposal and use – this is rated as green
  • 101,530t (tonnes dry solid) total volume dispatched
  • 19,508ha (hectares) land used for spreading
  • 98.9% of sludge dispatched was used in agriculture
  • 1 of 4 companies (out of 9) to report less than 100% satisfactory sludge disposal and use – all companies rated green

Annual compliance with sludge disposal and use metric by Anglian 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
Total volume of sludge dispatched (t thousands dry solid) 102.4 99.6 106.6 102.8 98.8

2016 to 2020 data

Year 2016 2017 2018 2019 2020
EPA status green green no data no data no data
Percentage of sludge compliant 100 100 no data no data no data
Total volume of sludge dispatched (t thousands dry solid) 103.7 98.2 110.2 90.6 82.5

2021 to 2025 data

Year 2021 2022 2023 2024 2025
EPA status no data green green no data no data
Percentage of sludge compliant no data 99.96 99.43 no data no data
Total volume of sludge dispatched (t thousands dry solid) 96.2 97.6 101.5 no data no data

Table note: for the 2018 to 2021 calendar years, we suspended the metric from the EPA whilst we reviewed our regulatory regime for sludge. The EPA RAG status thresholds are in the EPA metric guide.

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

Year Sewage sludge used in agriculture (t thousands) Sewage sludge recovered non-agriculture (t thousands) Sewage sludge disposed (t thousands)
2021 92.8 3.4 0.0
2022 95.0 2.6 0.0
2023 100.4 1.1 0.0

8. Supply Demand Balance Index (SDBI) metric

Main facts

For the financial year ending 2024:

  • SDBI of 100 – this is rated as green
  • 27 water resource zones
  • 1,150 megalitres per day water distributed into the network – above forecast
  • 1 of 9 companies (out of 9) to be rated green

Annual compliance with SDBI by Anglian Water, with EPA ratings

Financial year ending 2022 2023 2024 2025 2026
EPA status green green green no data no data
SDBI score 100 100 100 no data no data

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

9. Event Duration Monitoring (EDM) delivery

We have published the EDM storm overflow annual return dataset received from water companies. This shows how often and how long the monitored storm overflows operated during 2023. The 2023 dataset also includes water company reasons for performance issues with monitors and reasons for high spill counts.

Anglian Water storm overflows

Year 2023
Total number of active storm overflows listed in the annual return 1,432
Total number of active storm overflows with EDM commissioned 1,432
Percentage of active storm overflows listed with EDM commissioned 100
Total number of storm overflows with spill data 1,423
Percentage of storm overflows listed with spill data 91.0
Average number of spills per storm overflow with spill data 22.2
Average duration (hours) per monitored spill event 8.6
Percentage storm overflows with ≥90% EDM operation during reporting period 93.2