Integrated Catchment Management: UKWIR Supporting Research. Dr Arthur Thornton Regulatory Compliance and Research Atkins UKWIR

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1 Integrated Catchment Management: Supporting Research Dr Arthur Thornton Regulatory Compliance and Research Atkins

2 Developing integrated catchment management

3 Summary of key sources requiring quantification Regulator focus Key sources W ater Industry focus Trader Person care Cleaning products Urine/faeces al CS Runoff Town centre Light industry Domestic Agriculture WwTW Mine water Atmospheric deposition Waterbodies Plumbing leaching Highway Urban Geological Runoff

4 Key sources to be modelled Previous catchment planning dominated by SIMCAT Does not adequately describe diffuse sources To plan WFD PoMs need to consider ALL significant inputs WwTW discharges Sources to Other WwTW point sources Monitoring data GIS Agricultural Minewater Intermittent Highway urbanrunoff Atmospheric Natural Industry Septic tanks

5 Sewer Catchment Modelling: Example Output: Triclosan Source apportionment in sewer demonstrating potential control at source. Feeds forwards into WwTW model previous slide Triclosan (tonnes/year) Reported values Calculated as part of this project % of total urban catchments Toothpaste % Degraded Liquid soap % Solid soap % 70% Laundry % Domestic 49% Mouthwash % Dishwashing % Surface cleaners % To rivers Runoff 0% Sum Measured WwTW WwTW 4% Treatment Urban = Crude sewage Effluent & Output To estuaries Liquid soap % Public 100% 72% 7.2% 1.06 Solid soap % Services 25% 2% Dishwashing % Surface cleaners % Liquid soap % Trader 25% Sludge Land Solid soap % Dishwashing % 23% 2% Surface cleaners %

6 Example output: WwTW (NP) Modelling by substance and identify high concentrations in receiving water. Develop control scenarios and demonstrate impact including control at source Demonstrate cost implications of end of pipe solutions. Demonstrate limits of technical feasibility. Demonstrate CO2 emission impacts Inform POMs UK, (works specific)

7 Chemical Investigations Programme Collaborative project Environment Agency, Water Industry and fully supported by Ofwat. Budget 30M designed to deliver understanding of the chemicals risk and POMS for PR14. C1 - Investigations to quantify risk from chemicals - Screening of WwTW final effluents (a) a full suite of chemicals of interest; (b) a selected number of compounds where specific issues have been identified and (c) WwTW where follow-up monitoring of steroid oestrogens is required.

8 Chemical investigations Programme C2 - Investigations to assess treatment options for chemicals - these investigations have been proposed for a number of WwTW in each company so that the performance of commonly used treatment options and advanced treatments can be evaluated. C3a Catchment monitoring/modelling investigations to assess catchment sources and advanced treatment options. C3b and c investigations to provide information on possible advanced treatment technologies at a laboratory and pilot scale.

9 WW23: Improving catchment management and regulation: key elements Smarter consents Assessment tools (e.g. models) Asset performance (controls and costs) Project aim: Inform the regulation of water company wastewater assets to enable more flexibility and efficiency in meeting regulatory requirements.

10 Quantification of benefits of improved catchment regulation Maximising environmental benefits per unit cost Avoid investment with no environmental gain Reduced operational costs Reduced carbon emissions Reduced non compliance risk (avoidance of trivial non compliance) Promote control of other non water company sources of pollution (e.g. diffuse pollution) Consider source control and future trends in planning Consider linkage between water quality and water resources Integrated Catchment Management

11 Report structure: Executive Summary Chapter 1: Introduction : Catchment Based Consents as a concept potential options: Chapter 2: Catchment Based Consents : Define the concept and the requirements. Chapter 3: Chapter 4: Chapter 5: Chapter 6: Flexibility in existing Consenting: Head Room &Seasonal consenting Sampling points in catchment Examples Summary The future of Catchment management the Ecological perspective: Baci analysis ecological controls Risks and requirements Summary Catchment scenarios: SIMCAT (TSA) Methodology Examples optimised on different outputs: e.g. carbon, reach compliance Summary Real Time Control: Realistic assessment SWOT Examples Process assessment: Energy / carbon Summary Conclusions and Recommendations

12 Key concepts What can we control (i.e. treatment processes) e.g. aeration of activated sludge beds, iron dosing for phosphorus, tertiary treatment? When and where do we change treatment? What are we trying to optimise? Minimise pollution loads Maximise overall length of reaches achieving targets Achieve targets at key locations Concentrate effort where greatest benefit (e.g. if close to target) Compliance at all locations 17 June 2009 What can we most achieve with a finite pot of money? What should we do first? Priorities and timescales for investment

13 ILC Flow m3/day Effluent Quality P mg/l Testing of Real Time Control Consenting Options: Case Study: Flow based River Flow Effluent Quality P SIMCA T D/s on Stoke by Clare reach P removal P P Mean P removal Mean P Upper confidence limit P lower Confidence limit P removal Upper confidence limit P removal Lower confidence limit Downstream Quality vs River Flow No P Rem Flow P Rem Downstream Quality Flow Related Bas eline Simulated P mg/l June

14 Testing of Real Catchment Based Consenting Options: Case Study Spatial selection of P removal: Population equivalent threshold Treatment type Impact of individual works: 1 Impact on P conc at intakes 2 Impact on P load at intakes 3 Reduction in P conc x length of reach 4 Proportion of reduction required to meet WFD target x reach length 30 scenarios tested Contribution of each works (criteria 3)

15 Testing of Real Time Control and Catchment Based Consenting Options: Case Study Comparison of treatment effort (dosing days x p.e) with impact on river quality Downstream Control No P Removal 2500P.E Upstream PLoad Constant P Removal Flow Control 1000P.E Seasonal PConc Length Target Reduction P x Reach Length

16 Key features for RTC to be successful: System flexibility Is the system able to change? Response efficiency Can we control the effect? Response time How quickly can we efficiently make a change in the system? Scope of application Which parameters can be controlled using RTC approach? References availability Relevant examples from research studies and practical application

17 RTC-CONTROLLED URBAN WASTEWATER SYSTEM MANAGEMENT Global HIGH MEDIUM LOW Site specific RTC control techniques considered as examples: Chemical dose control UV treatment Bypassing process stages e.g. tertiary filters Feeding into different ASP zones to process stages Carbon source dose control to anoxic ASP zone for denitrification Aeration control in the aerobic ASP tank/zone Controlled pollutants loadings for inflow to the WwTW Moving walls to enable changing volume of aerobic, anoxic and anaerobic zones to optimise the process capacity in BNR plants Side stream nitrifiers growth and feed to the activated sludge process at the onset of storm event CRITERIA System flexibility Response efficiency Response time Scope of application References availability

18 Opportunities for RTC in Wastewater Networks: Optimise in system storage Fully utilise available storage capacity reduce loads on treatment process reduce CSO spills to the environment. Examples in UK and wider Utilising controls to link river quality and wastewater quality Storage can be utilised for higher load sewerage (first flush) Maximise hydraulic benefit of CSO spills (spill more dilute sewage) Reduce load on treatment process Some research, however limited implementation Predictive System (Intermittent & Continuous Discharges) Utilise rainfall, quality and river data to provide a full catchment solution across multiple drainage areas (spatial rainfall). Research only

19 Developing RTC Literature experience limited to sanitary pollutants rather than PHS/PS Major problem with the accuracy and reliability of online measurement devices at all system stages: will need to develop confidence in RTC control Linkage to monitoring and environmental parameters not established Benefits related to the headroom and flexibility in the consenting regime at specific sites Few actual RTC process options and will be site specific

20 Conclusions 1 The integrated catchment management may deliver benefits. These benefits are not easily defined and we need to recognise: The complexity of the consenting procedures What is really meant by headroom and its availability Seasonality and the impact of annual average consents How or where we measure compliance Understand the linkage between the consent conditions and the ecology Then having understood the real benefits we can start to link the tools Catchment management models and the appropriate data sets

21 Conclusions 2 Having established the benefits and the tools to link the monitoring to control we need to define the appropriate control. Biological processes have limited switching capability The non-biological (tertiary treatment of the future) may facilitate switching. These will be site specific solutions and appropriate process security will need to be established Failure of RTC may also be significant The roadmap to achieving integrated catchment management needs each of the elements of monitoring, managing control and technology to develop. This project has demonstrated where the benefits may lie but also the complex nature of the technical tasks that will need to be overcome to deliver the benefits.