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 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 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 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 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