Water industry perspective on managing water quality

Mark Morton Senior Hydrogeologist

Acknowledgements

• Arup – Gerd Cachandt, Lu Yang, Ellen McDonald, Thomas Sagris

• British Geological Survey – BGS, Holger Kessler, Andrew Farrant, Jon Ford, Jon Lee

• Cranfield University – Ian Holman • University of East Anglia – Sarah Wexler • Askham-Bryan College – Joseph Bonner • University of Leeds – Jared West, Simon Bottrill, Josie

McSherry • Environment Agency – Hannah Threadgould, Andrea

Lancaster, Andrew Pearson • Natural England – Paul Arnold • Yorkshire Water – Paul Speight, Andrew Walker, Gemma

Nicholson, John Haley

Yorkshire’s geology

Yorkshire

So what’s the problem?

02468

1012141618

Jan 79 Jan 82 Jan 85 Jan 88 Jan 91 Jan 94 Jan 97 Jan 00 Jan 03 Jan 06 Jan 09 Jan 12 Jan 15

Nitr

ate

conc

entr

atio

n m

g N

/L

Sample Date

Chalk raw water nitrate concentration mg N/L KILHAM WTW KILHAM WTW PCV

0

5

10

15

20

25

Jan 71Jan 74Jan 77Jan 80Jan 83Jan 86Jan 89Jan 92Jan 95Jan 98Jan 01Jan 04Jan 07Jan 10Feb 13Feb 16

Nitr

ate

conc

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n m

g N

/L

Sample date

Sandstone raw water nitrate concentration mg N/L ARMTHORPE NO 1 BHS ARMTHORPE NO 2 BHS ARMTHORPE NO 3 BHS

Also on other sites

0

2

4

6

8

10

12

14

16

18

20

1976 1982 1987 1993 1998 2004 2009 2014 2020 2025N

O3

mg/

l

Nitrate in Chalk Groundwater

BRIDLINGTON BHS - OUTLET BRID - HAISTHORPE WTW INLET

BURTON AGNES WTW - WORKS OUTLET BURTON A - HAISTHORPE WTW INLET

ELMSWELL WOLD BHS - OUTLET ELMSWELL WOLD WTW - WORKS OUTLET

ETTON WOLD WTW - WORKS OUTLET DWI Limit

Scale of the problem?

• YW Nitrate Safeguard Zones

Origin of nitrate in groundwater?

Nitrogen – Oxygen stable isotope analysis

0.0

0.5

1.0

1.5

2.0

2.5

3.0

3.0 4.0 5.0 6.0 7.0 8.0 9.0

δ18 O

NO

3 (‰

)

δ15NNO3 (‰)

Oxygen verses nitrogen stable isotope fractionation from groundwater samples

O-N stable isotope on ‘fingerprint’ plot

Groundwater ageing

196519701975198019851990199520002005201020152020

May-16 Aug-16 Nov-16 Mar-17 Jun-17 Sep-17 Dec-17

Armthorpe GW ageing

Armthorpe 1 Armthorpe 2

196519701975198019851990199520002005201020152020

May-16 Aug-16 Nov-16 Mar-17 Jun-17 Sep-17 Dec-17

Kilham GW ageing

Kilham 1 Kilham 2

Geological complexity

Geological complexity - drift

Why does it matter?

0200000400000600000800000

100000012000001400000160000018000002000000

0 100 200 300 400

m3/

d

licence day

Kilham abstractions compared to licence

2012

2013

2014

2015

2016

2017

Kilham Licence 02468

1012141618

Sep 72Sep 76Sep 80Sep 84Sep 88Sep 92Oct 96Oct 00Oct 04Oct 08Oct 12Oct 16

Nitr

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conc

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n m

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/L

Date

Nitrate mg/l Bh1 Bh2 Bh3 PCV

How do we move forward…

• Holistic approach • Catchment Management

– Farmer engagement – Top 10 agri solutions

• Better understanding – Drift geology – Solid geology – PHolistic

approachassive seismic – Necessary for

engagement • Government support

Cover crops Over winter stubble/ uncropped

Undersow with grass/legumes

Low/no till

Eco planting Early harvest potatoes/maize

Manage better manure/bag N

Improved cultivars

• Holistic approach • Pesticides • Sediment loss • Nutrients