CSO Monitoring and The Environment Agency

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2 Sensors For Water Interest Group Sewer Systems for the 21 st Century 25 th June The University of Sheffield CSO Monitoring and The Environment Agency Dr Philip Hulme Senior Advisor The Environment Agency

3 CSOs Statistics Network CSOs and direct at STWs inlet Inland and Coastal 17,684 permitted known overflows

4 AMP Investment (CAPEX) Improving Historic Unsatisfactory Overflows 7,000 + improved

5 Getting the Balance Right Environment Flooding Bills (Prioritising and Communicating)? CSO

6 Measures of CSO performance Definition of Unsatisfactory causes significant visual or aesthetic impact due to solids, fungus; causes or makes a significant contribution to a deterioration in river chemical or biological class; causes or makes a significant contribution to a failure to comply with Bathing Water Quality Standards for identified bathing waters; operates in dry weather conditions; operates in breach of permit conditions provided that they are still appropriate; causes a breach of water quality standards (EQS) and other EC Directives; and/or causes unacceptable pollution of groundwater. Modelled performance Emission Standard Environmental Standard (UPM) Source apportionment tools

7 Pollutions CSOs as a Source / Pathway Pollution Incidents Report September 2013 Category 1 & 2 Pollutions encouraging companies to self-report, which will demonstrate better knowledge of assets and enable a faster response to help limit damage to the environment

8 Future Pressures on Sewerage (CSOs are often the first to show the symptoms) OFWAT Future Impacts on Sewer Systems 2011» Climate change, growth, urban creep by 2040 = increase in flood volumes of about 51% DEFRA Statement of Obligations 2012» Water companies must understand how their networks currently perform and how they interact with other drainage systems, so that they can effectively manage future pressures. EA / Ofwat Drainage Strategy Framework 2013» Improve understanding of network performance (and improve models) by using long term flow and level monitoring on sewers and CSOs. UK Government Water Act 2014 Resilience Duty» Promote action to respond effectively to pressures on the environment (including climate change), population growth and changes in behaviour

9 What is Monitored now? 9

10 How Often do CSOs Spill? Regulatory EDM overflows * 42% did not spill * 79% spilt less than 10 times * 89% spilt less than 20 times * 97% spilt less than 50 times * BUT dry years * Mostly Coastal Overflows 10

11 Ministerial Direction Richard Benyon Letter to Water and Sewerage Company CEOs July water company understanding where its CSO assets are and how they are performing is a basic element of sound sewerage management I believe that water companies need to introduce monitoring for the vast majority of their CSOs by 2020.

12 Ministerial Direction (Specific messages) Previous Performance Improvements Legitimate Safety Valve Understandin g Performance Changes in Performance Monitor Vast Majority by 2020 Reputational Issue Monitoring approach should be risk based Inform Discussions with Customers Existing Monitoring and Customer Engagement High Frequency / Unsatisfactor y CSOs Future Pressures on Sewerage Compliance with Legislation Include Monitoring in Permits Strategy to deal with High Frequency CSOs

13 Why Monitor for Spill Occurrence and not flow or quality? Monitoring to record spill events and duration is fit for purpose (Event Duration Monitoring EDM) Cost Practicalities Simplify data analysis Screening tool

14 Risk Based Approach to the Monitoring of Storm Discharges Developed by the Environment Agency Consultation with WaSCs, Defra, Ofwat and MCS, SAS September 2013 Sets out implementation of Ministerial Ask for PR14 CSOs = Any combined sewer storm discharges from Network, Inlet Direct, PSs, Storm Tank

15 What does Vast Majority mean? High Significance Amenity Medium Significance Low Significance Spill Frequency

16 What does Vast Majority mean? Amenity Spill Frequency

17 Amenity Based on AMP2 definition Modified to prioritise public health risk The highest amenity class downstream of the discharge point within the water body that the discharge is.

18 Spill Frequency Average number of annual spills based on a minimum 5 year record. 12/24 hour spill counting method. Modelled spill data or available monitored data. In the absence of model or monitored data the default is that EDM will apply for high and moderate amenity sites. For Low and Non amenity sites, in the absence of modelled or monitored spill frequency (20 or more spills) information then a risk assessment may be applied

19 EDM Requirements High Significance Event Duration Monitoring with Telemetry Telemetry Option to measure volume of the spill Where agreed locally provide live warnings Monitor the spill at 2 min intervals. 12/24hours procedure Information to be made available to the Environment Agency on request or as agreed locally plus an annually or 6 monthly (for bathing waters) reported spill summary report These requirements also apply to PR14 EDM1 (immersion), rb5 (bathing waters) and S8 (shellfish water) drivers. Early Delivery in PR14

20 EDM Requirements Medium Significance (Moderate Amenity) Monitor the spill at 15 min intervals. Telemetry optional. 12/24hours procedure Annually reported spill summary report, detailing number of annual spill events (12/24 counting) and total duration of spills for each overflow with EDM. Where there is concern or clarification required over performance, then more detailed information will be requested as set out for High Significance EDM requirements, Phased delivery in PR14

21 EDM Requirements Medium Significance (Low or Non Amenity) Monitor the spill at 15 min intervals. 12/24hours procedure Annually reported spill summary report, detailing number of annual spill events (12/24 counting) and total duration of spills for each overflow with EDM. Where there is concern or clarification required over performance, then more detailed information will be requested as set out for High Significance EDM requirements, Phased delivery in PR14

22 EDM Requirements Low Significance No EDM Required Review EDM requirement if changes in : performance indentified from models or change in amenity Future EDM investment funded through future AMPs

23 PR14 Guidance EDM Spill Frequency Permitting Flow EDM S8 Shellfish rb5 Bathing Waters EDM1 Water Immersion EDM2 - (Risk Based Approach)

24 Good Practice Guide Being developed by the Water Industry Informed the Environment Agency s Risk Based Approach

25 How will the data be used? Permit Spill Frequency Engage with Customers Real Time Reactive Network Management Real Time Informing Users Beach / Shellfish Defend Regulatory Challenge Resilience Duty (Climate/Gro wth, Creep) Inform WaSC Strategy & Prioritise Investment Confirm success of Capital Schemes Source Apportionme nt Inform Other s Strategy Respond to Media Verify Hydraulic Models Assess Long Term Trends

26 What Next? Agree Reporting Format & Process Routine (Annual / Six Monthly) Adhoc Agree Permitting Words Confirm List of Obligations and Audit Trail Include in Permits Inclusion in Business Plans Installation

27 CSO Monitoring and The Environment Agency Dr Philip Hulme Senior Advisor Environment Agency