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Presentation Geological Society - Hydrogeology Group Groundwater Asset Management Shropshire Groundwater Scheme Kevin Voyce Hydrogeologist Midlands Region Groundwater & Contaminated Land Team 10 September 2008 Presentation • SGS Role in Strategic Water Resource Planning & Operations – River Severn Regulation • Development of the Scheme to date • Environmental Management • System Management 1 LLYN CLYWEDOG OPERATIONS 2006 100 3 500 Flo od Drawdo wn 90 20 06 % Storage 3 000 80 Shro ps hire Temp orary Floo d Drawdo wn Ground wate r 70 2 500 60 Se ek Drought Orde r 2 000 50 1 500 40 Dro ug ht Orde r PERCENTAGE FULL PERCENTAGE In Fo rce FLOW AT BRYNTAIL (Ml/d) BRYNTAIL AT FLOW 30 1 000 Rele ase or Overflo w 20 5 00 10 0 0 1- Jan 1 -Feb 1-Mar 1-Apr 1- May 1- Jun 1- Jul 1- Aug 1-Sep 1-Oct 1- Nov 1- Dec 2 Clywedog: Proposed Control Curves 2006 - scenario from 21st Aug 100 90 80 70 60 50 S torage S(%) torage 40 Floo d Draw Dow n Zone Hydr opow er Release Zone 30 SGS Zon e 1 - up t o 75 Ml/d Net SGS Zon e 2 - up t o 150 Ml/d Net SGS Zon e 3 - up t o 225 Ml/d Net Auto matic Dro ught Or der Zone 20 % Stora ge 2 006 Forec ast Prof ile 250 Ml/d Forec ast Prof ile 300 Ml/d Forec ast Prof ile 350 Ml/d 10 Forec ast Prof ile 400 Ml/d Forec ast Prof ile 450 Ml/d Forec ast Prof ile 500 Ml/d 0 Jan Feb Mar A pr May Jun Jul Aug S ep Oct Nov Map derived from 1:250,000 scale BGS mapping under licence 2003/014 3 4 Shropshire Groundwater Scheme – Gross Deployable Yields and Operational Years Phase Gross Yield Regulation Seasons Requiring SGS Support Phase 1 45Ml/d 1984, 1989, 1995, 1996, 2006 (commissioned 1984/85) Phase 2 50Ml/d 1995, 1996, 2006 (commissioned 1991) Phase 3 50Ml/d 2006 (commissioned 1999) Phase 4 45-50Ml/d 2006 (commissioned 2005) Phase 5 60-65Ml/d est. Underdevelopment Phase 6 20-25Ml/d est. Not developed Phase 7 35-40Ml/d est. Not developed Phase 8 40-45Ml/d est. Not developed TOTAL SCHEME (ma x 330Ml/d) Environmental Management • Groundwater level monitoring & resources assessment • Crop vulnerability mapping • Ecological monitoring • Hydro-chemical monitoring & assessment 5 Legislative Drivers • 1979 SGS Public Inquiry • Model Terms & Conditions Agreement • 1981 SGS Abstraction Licence • Water Resources Act 2003 • CAMS - Catchment Abstraction Management Strategies 6 NORTH 1- TAN HOUSE 6- FRANK BROOK Abs 11- KNOLLS Abs No 2 SOUTH 2- EYTON 7- FRANK BROOK Obs 12- KNOLLS Abs No 1 3- FENEMERE Obs 8- YEATON MANOR FARM 13- KNOLL Obs 4- FENEMERE TW 9- BANK HOUSE Abs 14- FORTON Abs 5- WALFORD Obs 10- NIB HEATH Fenemere Pool War Brook 1 River 12 2 3 4 War Brook Perry 10 11 13 5 8 6 9 14 7 River Severn NORTHWICH HALITE T L U A F M E W PERMIAN LOWER MERCIA KINNERTON MUDSTONE SANDSTONE Shropshire Groundwater Scheme Phase 2 South Perry & Montford Hydrogeological Cross Section 7 8 9 10 11 Tern Hill Gauging Station - SGS Helshaw Out Fall 6.58 Ml/d Gross Out Put SGS Stoke on Tern Out Fall 6.69 Ml/d Gross Out Put (Potford brook) - Eaton upon Tern Gauging Station (Platt Brook) (River M eese) - Potford Brook at Sandyford Bridge Gauging Station - Direction of River Flow SGS Waters Upton Out Fall 32.58 Ml/d Gross Out Put (River Strine) (River Tern) -WalcotGauging Station 1747.RE.DTotal 2012.FQ.i r 400 300 FQ [Ml/d] FQ 200 100 25 20 15 10 RF [mm] RF 5 0 01/08/1996 11/08/1996 21/08/1996 31/08/1996 10/09/1996 20/09/1996 30/09/1996 10/10/1996 20/10/1996 30/10/1996 12 400 600 Very fas t 350 Ve ry fast 500 300 Fa st Fa st Avera ge 400 Average 250 Slow Slow 200 300 Ve ry s low Length (mm) Length (mLength m) Very slo w 150 200 x River Tern x River Tern 100 Percentage standard growth Percentage standard growth = 110 % = 124 % 100 5 0 0 0 1 2 3 4 5 6 7 8 9 10 11 1213 1 2Age (y e ars ) 3 4 Age (yea rs) Graph to show the growth of chub in R iver Tern compared to the standard grow th of chub in Graph to show the growth of brown trout in River Tern compared to the standard growth of 'southern' rivers (National Fisheries Laboratory unpublished data) brown trout in rivers (National Fisheries Laboratory unpublished data) Brown Trout Club 13 Hydro-chemical Monitoring • Baseline (non-operational) & Operational sampling regimes • Early analysis - nutrients, metals, & major ion chemistry • Organic chemistry - Pesticides, Herbicides & Hydrocarbons • Gas Chromatography Mass Spectrometry (GCMS) Manganese projections at Stoke on Tern (EQS 30 ug/l) 60 Upstream Stoke onTern 50 Downstream 40 Stoke onTern 30 Resu lt (ug Resu lt /l) 20 Blended outfal l Stoke onTern 10 0 06-Aug-05 12-Aug-05 18-Aug-05 24-Aug-05 30-Aug-05 05-Sep-05 11-Sep-05 17-Sep-05 Date U/S Stoke on Tern D/S Stoke on Tern Blended outfall Stoke on Tern EQ S 14 Borehole Yield - MSc Study • Comparison of operational yields and repeat step test v baseline specific capacity • Hydro-chemical modelling showed water to be supersaturated with iron species haematite, magnetite, geothite & ferrihydrite • Microbial testing confirmed presence of iron & sulphur reducing bacteria and slime forming bacteria – Iron reducing bacteria (greater mobility) – Slime forming bacteria (catalyst to encourage Fe & Mn precipitation) • 6 out 42 boreholes proven to have >5% yield loss. Coincide with areas of localised confined aquifer (thick drift) giving rise to reducing conditions (Phase 2 & 5) low DO & elevated Fe & Mn System Management • Asset management plans • Routine turnover of pumps & scheduled maintenance • Telemetry monitoring, interrogation & operation • System performance 15 Pipeline contr ol valve Borehole Ch ambe r Flow met er Cha mber Sand Trap & Aerati on Cha mber Out fall str uctur e Pipeline 16 Energy Consumption 2006 • Combination of up to 4 Phases • Target Daily Yield 100Ml/d • Total Vol Pumped 4,752 Ml • Total Energy units 1,211,012 kWh • Electricity Cost £66,989 17 Energy Performance Evaluation • Hodnet Abstraction Pump • Operating Flow 6.02 Ml/d • Head 44m • Energy & Carbon Emission Savings Annual kWh Savings = 7,230.65 (£557.12) kWh/Ml Savings = 9.872 kgCO 2/kWhr = 0.43 Estimated Annual CO 2 Savings (tonne) = 3.11 18 Concluding points • Shropshire Groundwater Scheme - Role in Strategic Water Resource Planning & Operations • Environmental Management • System Management 19.
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