Delivering Environmental Outcomes in a TOTEX world Rachel Fox Scottish Water Scottish Water- Our Activities Glasgow Catchment Proposed consent (2010) 5 mg/l BOD (WFD 2027) 1mg/l Ammonia (WFD 2027) 1 mg/l Phosphorus (UWWTD MOU) Daldowie WWTW Tidal Weir Dalmarnock WWTW Agreed strategy - transfer scheme Daldowie WWTW Tidal Weir Dalmarnock WWTW Emerging Evidence – impact on tunnel solution This is a civil engineering solution to a process engineering problem! Daldowie WWTW Tidal Weir Dalmarnock WWTW Innovative Treatment Solution? Innovative Treatment Solution - Nereda Proposed layout 6x Nereda towers Collaborative Technology Trials • Granule stabilisation • Shock loads • Cold weather • Wet weather • ‘Warm’ weather • Sludge properties Nereda trial - technical success 12 11 10 9 8 7 6 mg/l 5 4 3 2 1 0 TSS BOD TP ammonia SRP Emerging Evidence WFD classification in the Lower River Clyde 2007 2008 2009 2010 2011 2012 2013 2014 draft 2015 WATER QUALITY Dissolved oxygen Moderate Moderate Moderate Moderate Moderate Good High Good Good Biological oxygen demand Moderate - Good Good Good Good High Good Moderate Ammonia Moderate Moderate Moderate Moderate Moderate Moderate Good Good Good ECOLOGY Diatoms Moderate Moderate Moderate Poor Moderate Moderate Moderate Moderate Moderate Invertebrates Bad Bad Bad Poor Poor Poor Bad Poor Moderate High Good Question WFD need for investment Moderate Poor Bad UWWTD P focus 3+ 3-n + Al + HnPO4 ↔ AlPO4 + nH 3+ 3-n + Fe + HnPO4 ↔ FePO4 + nH Wastewater in Wastewater out Ferric dosed Phosphorus in sludge UWWTD P focus Daldowie WWTW Dalmarnock WWTW UWWTD P focus: catchment considerations Dalmuir WWTW (PFI) Daldowie STC (PFI) Paisley Daldowie WWTW WWTW Shieldhall WWTW Dalmarnock WWTW UWWTD P focus: catchment considerations Dalmuir WWTW (PFI) Daldowie STC (PFI) Paisley Daldowie WWTW WWTW Shieldhall WWTW Dalmarnock WWTW UWWTD P focus: catchment considerations Daldowie STC Sludge drier Dosing Ferric Dalmuir PFI Dalmarnock Daldowie WWTW Tidal Tidal Weir Clyde estuary River Clyde Other Glasgow Sites Shieldhall Too many metal ions= Thermite & Liquor plant reaction? issues? UWWTD P focus: catchment considerations Daldowie STC Sludge drier Dosing Dosing Ferric Ferric Dosing Dalmuir PFI Dalmarnock Ferric Daldowie WWTW Tidal Tidal Weir Clyde estuary River Clyde Other Glasgow Sites Shieldhall Sludge off site Centrifuge Temporary trial Temporary trial 7 Dalmarnock Daldowie 7 6 6 (mg/l) 5 5 4 4 3 3 2 2 1 1 Total Phosphorus Phosphorus Total 0 0 Influent Dosed Effluent Influent Dosed effluent AluminiumUWWTD P focus: solution catchment considerations Daldowie STC Sludge drier Dosing Dosing Ferric Ferric Dosing Dalmuir PFI Dalmarnock Ferric Daldowie WWTW Tidal Tidal Weir Clyde estuary River Clyde Other Glasgow Sites Shieldhall Sludge off site Centrifuge AluminiumUWWTD P focus: solution catchment considerations Daldowie STC Sludge drier Dosing Dosing Ferric Aluminium Dosing Dalmuir PFI Dalmarnock Al Daldowie WWTW Tidal Tidal Weir Clyde estuary River Clyde Other Glasgow Sites Shieldhall Best TOTEX solution Whole Life Cost Life Whole Transfer Nereda Ferric Aluminium Chemical compliance: 10 months of data 7 6 5 (mg/l) 4 3 2 1 Total Phosphorus Phosphorus Total 0 Daldowie Influent Daldowie Final Dalmarnock Influent Dalmarnock Final Effluent Effluent Partnership Success • Willingness to consider new evidence • Willingness to adjust expectations • Deferral of WFD driver pending further evidence • TOTEX approach to environmental improvement and compliance Thank you .