drinking water quality problems and solutions

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Drinking Water Quality

T h i s t e x t b o o k p r o v i d e s a c o m p r e h e n s i v e r e v i e w o f t h e p r o b l e m s a s s o c i a t e d w i t h

t he s up pl y o f d ri nk in g w at er i n t he d ev el op ed w or ld . S in ce t he r s t e d it i on o f

t hi s b oo k w as p ub li sh ed t he re h av e b ee n e no rm ou s c ha ng e s i n t he w at er

i n du s tr y, e s pe c ia l l y i n t h e w a y d r in k in g w a te r i s p e rc e i ve d a n d r e gu l at e d.

Wa t er c o mp a ni e s a n d r e gu l at o rs h a ve b e en p r es e nt e d w i th n u me r ou s n e w

challenges g l o ba l w ar m i ng h a s s e ri o us l y a f fe c te d t h e s u st a in a bi l i ty o f w a te r

s u p p l i e s a s w e l l a s i m p a c t i n g w a t e r q u a l i t y ; a d v a n c e s i n c h e m i c a l a n d m i c r o b i a l

a n al y si s h a ve r e ve a l ed m a ny n e w c o nt a m in a nt s i n w a te r t h at w e re p r ev i ou sl yu n de t e ct a bl e o r u n kn o wn ; a n d r e ce n t t e rr o ri s t a t ta c ks h a ve d e mo n st r at e d h o w

v u ln e ra b le w a te r s u pp l ie s c o ul d b e t o c o nt a mi n a ti o n o r d i sr u pt i o n. T h is n e w

e di ti on i s a n o ve rv ie w o f t he c ur re nt a nd e me rg in g p ro bl e ms , a nd w ha t c an b e

d o n e t o s o l v e t h e m . I t h a s b e e n c o m p l e t e l y u p d a t e d , a n d i n c l u d e s t h e n e w W H O

R e v i se d D r i nk i n g Wa t e r G u i d el i n e s.

Drinking Water Quality i s a n i d ea l t e xt b oo k f o r c o ur s es i n e n vi r on m en t al

s c i e n ce , h y d ro l o g y, e n v i ro n m en t a l h e a l t h, a n d e n v i ro n m e nt a l e n g i ne e r i n g. I t

a l s o p r o v i d e s a n a u t h o r i t a t i v e r e f e r e n c e f o r p r a c t i t i o n e r s a n d p r o f e s s i o n a l s i n t h e

w a t e r s u p pl y i n d u st r y.

N. F. GRAY is a Professor at the Centre for the Environment at Trinity College,

D ub li n. H e h as w or ke d i n t he a re a o f w at er t ec hn ol og y f or 3 0 y ea rs , a nd i s

i n te r na t i on a ll y k n ow n a s a l e ct u re r a n d a u th o r i n w a te r q u al i t y a n d p o l l u ti o n

c o nt r ol . H i s r e se a rc h s p ec i a li z es i n t h e o p er a ti o na l p r ob l em s a s so c ia t ed w i th

s u p pl y i n g d r i n ki n g w a t e r a n d t r e a t in g w a s te w a t e rs .


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Drinking Water QualityS e co n d E d it i on

N. F. Gray

U n iv e rs i ty o f D u bl i n


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Contents

Preface page xiii

Acknowledgements xvi

Part I Introduction to water supply

1 The water business 3

1 .1 I n t r od u c t io n 3

1 . 2 Wa t er c o ns u mp t i on 3

1 . 3 A c ce p ta b le w at e r q u al i ty 7

1 . 4 Wa t er u t il i ti e s 10

1 .5 Wa t e r c o n s e r va t i o n 18

1 .6 C o n c lu s i on s 33

References 35

2 Drinking water standards and risk 372 .1 I n t r od u c t io n 37

2 . 2 D e ve l op m en t o f q u al i ty s t an d ar d s 37

2 . 3 R i sk a s se s sm e nt i n t h e d e ve l o pm e nt o f h e al t h- b as e d t a rg e ts 39

2 . 4 Wa t er s a fe t y p l a n s 42

2 . 5 D ri n ki n g w a te r s t an d ar d s 52


References 64

3 A quick guide to drinking water problems 65


3 .2 T he p ro bl e ms 66


References 73

Part II Problems with the resource

4 Sources of water 77


4 .2 T he w at er c yc le 77

4 . 3 S ur f ac e w a te r s: l a ke s , r e se r vo i rs a n d r i ve r s 80

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4 . 4 G ro u nd wa t er s o ur c e s 89

4 .5 O th er s ou rc e s o f w at er 99

4 .6 C o n c lu s i on s 112

References 114

5 Nitrate and nitrite 116

5 .1 S ou rc es i n w at er 116

5 . 2 Wa t er q u al i ty s t an d ar d s 119

5 . 3 E f fe c t o n c o ns u me r s 120

5 . 4 N i tr a te i n g r ou n dw a te r s 123

5 .5 N it ra t e i n s ur fa ce w at er s 125

5 . 6 C on t ro l o f h i gh - ni t ra t e w a te r 126

5 .7 C o n c lu s i on s 132

References 134

6 Pesticides and organic micro-pollutants 137

6 .1 O r g an i c m i c r o - p ol l u t a nt s 137

6 . 2 P e st i c id e s 139

6 . 3 I n du s tr i al s o lv e nt s 156

6 .4 P o l yc y c l i c a r o m a t i c h y d r o ca r b o ns 160

6 . 5 R e mo v al o f o r ga n ic c o nt a mi n an t s f r om d r in k in g w a te r 162

6 .6 C o n c lu s i on s 163

References 165

7 Endocrine-disrupting compounds and PPCPs 169

7 . 1 I n tr o du c ti o n a n d d enitions 1697 . 2 P ha r ma c eu t ic a l a n d p e rs o na l c a re p r od u ct s ( P PC Ps ) 171

7 . 3 O e st r og e n a n d f e rt i l it y 174

7 .4 C o n c lu s i on s 177

References 179

8 Odour and taste 181


8 . 2 S t an d ar d s a n d a s se s sm e nt 181

8 .3 C la ss ication 183

8 . 4 O do u r- c au s in g s u bs t an c e s o f n a tu r al o r ig i n 1858 .5 M a n -m a d e o d o u r - c a us i n g s u b s t a n ce s 188

8 .6 C o n c lu s i on s 188

References 189

9 Metals 191

9 .1 I ro n 191

9 . 2 M an g an e se 193

9 . 3 A rs e ni c 194

9 .4 O th er m et al s 196

9 . 5 R e mo v al b y t r e a t me n t 198

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9 .6 C o n c lu s i on s 199

References 200

10 Hardness and total dissolved solids 203

1 0 .1 I n t r o du c t i on 203

1 0 .2 C h em i st r y o f h a rd n es s 203

1 0 .3 S t an d ar d s 205

1 0 .4 H e al t h a s p e ct s 206

1 0 .5 C o n c lu s i o ns 207

References 208

11 Algae and algal toxins 210

1 1 .1 I n t r od u c t i on 210

1 1. 2 P r ob l em s a s so c ia t ed w i th a l ga e 210

1 1 .3 S t a nd a r d s 2131 1 .4 T r ea t m e nt 213

1 1 .5 C o n cl u s i on s 214

References 215

12 Radon and radioactivity 217

1 2 .1 I n t r o du c t i on 217

1 2. 2 R ad on 218

1 2 .3 N o n - ra d o n r a d i o n u cl i d e s 219

1 2 .4 S t an d ar d s a n d t r ea t me n t 220

1 2 .5 C o n c lu s i o ns 222References 223

13 Pathogens 225

1 3 .1 I n t r o du c t i on 225

1 3 .2 P r ot o zo a 225

1 3 .3 Vi r us e s 229

1 3 .4 B a ct e ri a 231

1 3 .5 U n us u al s o ur c es o f c o nt a mi n a ti o n 235

1 3 .6 C o n c lu s i o ns 237

References 239

Part III Problems arising from water treatment

14 Water treatment 245

1 4 .1 I n t r o du c t i on 245

1 4 .2 U n it p r oc e ss e s 246

1 4 .3 P r oc e ss s e le c ti o n 260

1 4 .4 H o w p r o bl e m s a r i se 261

1 4 .5 C o n c lu s i o ns 267

References 268

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15 Aluminium and acrylamide 270

1 5 .1 A l um i ni u m 270

1 5 .2 A c r y la m i d e 277

1 5 .3 C o n c lu s i o ns 278References 279

16 Odour and taste 282

1 6. 1 S ou rc e o f o do ur a nd t as te p ro bl em s 282

1 6 .2 R e mo v in g o d ou r s a n d t a st e s 283

1 6 .3 C o n c lu s i o ns 285

References 285

17 Fluoridation 286

1 7 .1 I n t r od u c t i on 286

1 7 .2 F l uo r id e a d di t i on 2871 7 .3 F l uo r id a ti o n a n d h e al t h 289

1 7 .4 F l uo r id a ti o n a n d p u bl i c o p in i on 291

1 7. 5 W ho i s a t r is k 292

1 7 .6 C o n c lu s i o ns 293

References 295

18 Disinfection by-products 297

1 8 .1 F o rm a ti o n 297

1 8 .2 S t an d ar d s 300

1 8 .3 H e al t h r i s ks 3011 8 .4 P r ev e nt i on o f b y -p r od u ct f o rm a t io n 302

1 8 .5 C o n c lu s i o ns 303

References 304

19 Monitoring and removal of pathogens 307

1 9 .1 I n t r od u c t i on 307

1 9 .2 M o n i to r i n g p a t h og e n s 307

1 9 .3 M e as u re m en t a n d s t an d ar d s 308

1 9 .4 H e te r ot r o ph i c p l at e c o un t s 313

1 9 .5 R e mo v al o f p a th o ge n s 314

1 9 .6 D i s i nf e c t i on 316

1 9 .7 C o n c lu s i o ns 317

References 320

Part IV Problems arising in the distribution network

20 The distribution network 325

2 0 .1 I n t r od u c t i on 325

2 0 .2 S e rv i ce r e se r vo i rs 325

2 0 .3 Wa t er m a in s 327

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2 0 .4 S e rv i ce p i pe s 328

2 0 .5 C o n c lu s i o ns 332

References 333

21 Aesthetic quality 3342 1. 1 O do ur a nd t as te 334

2 1 .2 D i sc o lo u ra t io n a n d i r on 335

2 1 .3 S e di m en t a n d t u r b id i ty 338

2 1 .4 C o n c lu s i o ns 340

References 340

22 Asbestos 342

2 2. 1 T he n at ur e o f a sb es to s 342

2 2 .2 H e al t h e f fe c ts a n d s t a n da r ds 344

2 2 .3 A sb e st o s c e me n t d i st r ib u ti o n p i pe s 3452 2 .4 C o n c lu s i o ns 346

References 348

23 Coal-tar linings and polycyclic aromatic hydrocarbons 350

2 3 .1 I n t r o du c t i on 350

2 3 .2 C o n c lu s i o ns 351

References 352

24 Animals on tap 353

2 4 .1 M i cr o bi a l s l im e s i n d i st r ib u ti o n p i pe s 3532 4 .2 Wa t er s up p li e s 355

2 4 .3 C o mm o n s p ec i es a n d r e m e d ia l m e as u re s 356

2 4 .4 S a mp l in g w a te r m a in s f o r a n i m al s 361

2 4 .5 M i cr o bi a l p a th o ge n s a n d i n ve r te b ra t e s 362

2 4 .6 C o n c lu s i o ns 363

References 364

25 Pathogens in the distribution system 366

2 5 .1 I n t r o du c t i on 366

2 5 .2 M i c r ob i a l c o n t a m i na t i o n 366

2 5 .3 C o nt r ol 3692 5 .4 D r in k in g w a te r s e cu r it y 370

2 5 .5 C o n c lu s i o ns 370

References 371

Part V Problems in household plumbing systems

26 Household plumbing systems 375

2 6. 1 E nt ry t o t he h om e 375

2 6 .2 P l um b in g s y st e ms 375

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2 6 .3 Wa t er B y el a ws a n d r e gu l at i on s 380

2 6 .4 C o n c lu s i o ns 381

References 381

27 Corrosion and metal contamination from pipework

and ttings 382

2 7 .1 I n t r od u c t i on 382

2 7 .2 C o rr o si o n 382

2 7. 3 L ea d 387

2 7 .4 C o pp e r 400

2 7. 5 Z in c 403

2 7 .6 C o n c lu s i o ns 403

References 404

28 Micro-organisms, bres and taste 4072 8 .1 M i cr o -o r ga n is m s i n p l um b in g s y st e m s 407

2 8 .2 F i br e s, i n cl u di n g a s be s to s 410

2 8. 3 O do ur a nd t as te 411

2 8 .4 C o n c lu s i o ns 412

References 413

Part VI The water we drink

29 Alternatives to tap water 417

2 9 .1 I n t r od u c t i on 417

2 9 .2 B o tt l e d w a t er 417

2 9 .3 P o in t -o f -u s e w a te r t r ea t me n t 428

2 9 .4 Wa t er h a rv e st i ng 436

2 9 .5 C o n c lu s i o ns 438

References 441

30 Water security in the twenty-rst century 442

3 0 .1 I n t r od u c t i on 442

3 0 .2 Vu l n e ra b i l i ty a s s es s m e nt 444

3 0 .3 D e ve l op i ng s e cu r it y p l an s 4443 0 .4 T h e e m e r ge n cy r e sp o ns e p l an 447

3 0 .5 C o n c lu s i o ns 450

References 451

31 Final analysis 453

3 1 .1 I n t r od u c t i on 453

3 1 .2 C o mp l ai n ts 454

3 1 .3 P u bl i c p e rc e pt i o n o f d r in k in g w a te r q u al i ty 455

3 1. 4 T he q ua li ty o f d ri nk i ng w at er 457

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3 1 .5 Wa t er u sa g e a n d c o ns e rv a ti o n 460

3 1. 6 Wa te r c onict 461

3 1 .7 D r in k in g w a te r i n d e ve l op i ng c o un t ri e s 461

3 1 .8 C o n c lu s i o ns 465

References 468

Appendix 1 EC Drinking Water Directive (98/83/EEC) quality

parameters 469

Appendix 2 US National Primary and Secondary Drinking Water

S t an d ar ds o f t h e U S E n vi ro n me n t al P ro t ec t i on A g en c y

(2006) 471

Appendix 3 World Health Organization drinking water guide values

for chemicals of health signic a n c e. H e a l th - r el a t e d g u i d e v a l u es

h av e n ot b ee n s et f or a n um be r o f c he mi ca l s t ha t a re n ot c on si de re d

h a za rd o us a t c o nc e nt r a ti o ns n o rm a ll y f o un d i n d r in k i ng w a te r,

a l th o ug h s o m e o f t h es e c o mp o un d s m a y l e ad t o c o ns u me r c o mp l ai n ts

o n a e st h et i c g ro u nd s . T h es e a re l i st e d i n Ta b le 2 . 6 488

Appendix 4 Major pesticides and their degradation (breakdown)

products with their relative toxicity limits in drinking water.

T he t ox ic it y i s b as e d o n l im it s s et o ri gi na l ly b y t he F ed er al

Health Authority in the former Federal Republic of Germany

(Miller e t a l. , 1 99 0 ), w h er e c a te g or y A p e st i c id e s s h ou l d n o t

e x ce e d 1 mg l1, category B 3 mg l1 a nd c at eg or y C 1 0mg l1 492

Appendix 5 EC Water Framework Directive (2000/60/EC) Priority

Substances 496Appendix 6 List I and List II substances covered by the EC Dangerous

S u b s ta n c e s D i r ec t i v e ( 7 6 / 46 4 / E EC ) 498

Appendix 7 The USEPA second Drinking Water Contaminant

C a nd i da t e L i st ( C C L) p u bl i sh e d i n F e br u ar y 2 0 05 499

Glossary 501

Index 508

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P re fa ce t o t he s ec on d e di ti on

S i nc e w ri t in g t h e r st e di t io n t he re h av e b ee n e n or mo us c ha ng es i n t he w at er

i n d u s t r y e s p e c i a l l y i n t h e w a y d r i n k i n g w a t e r q u a l i t y i s p e r c e i v e d a n d r e g u l a t e d .

That r s t e d i t i o n w a s w r i t t e n a t t h e s a m e t i m e a s t h e 1 9 9 3 r e v i s i o n o f t h e W o r l d

H e al t h O rg a ni z at i on ( W HO ) g u id e li n es a s p u bl i sh e d, w hi c h h a s s u bs e qu e nt l y

r e s u l t e d i n t h e r e v i s i o n o f a l l t h e m a j o r d r i n k i n g w a t e r s t a n d a r d s , i n c l u d i n g t h o s ec ov er i ng t he E ur op ea n U ni on a nd t he U SA . T ha t e ar ly e di ti on r ee c t e d t h o se

c ha ng es . S o t he p re pa r at io n o f t hi s n ew e di ti on w as t im ed t o c oi nc id e w it h t he

publication, late in 2004, of the latest revision of the drinking water guidelines

by the WHO, which has adopted a more rigorous health-based approach in

s e t t i n g g u i d e l i n e s . T h e s e n e w g u i d e l i n e s h a v e b e e n u s e d a s t h e b a s i s o f t h i s n e w

edition.

T h e p r o b l e m s a s s o c i a t e d w i t h g l o b a l w a r m i n g l e a d i n g t o r e g i o n a l c h a n g e s i n

c l i m a t e a n d w a t e r a v a i l a b i l i t y a r e s e r i o u s l y a f f e c t i n g s u s t a i n a b i l i t y o f s u p p l i e s a s

w el l a s s er io us ly i mp ac ti ng o n q ua li ty. A dv a nc es i n c he mi ca l a nd m ic ro bi al

a n al y si s h a ve r e ve a l ed t h at w at e r c o nt a i ns m a ny n e w c o nt a mi n an t s t h at w e repreviously undetectable or unknown, constantly presenting water utilities and

r eg ul at ors wi th ne w c ha ll en ge s. Al so t he r ec ent t err ori st a tt ac ks h ave

d e m o ns t r a te d h o w v u l n e r a b le w a t e r s u p p l i es a r e t o c o n t am i n a t io n o r d i s r up t i o n.

T h u s , w h i l e t h e e x i s t i n g r i s k s r e m a i n a n d n e e d t o b e d e a l t w i t h o n a d a y - t o - d a y

basis, these new problems require innovative technical and management

s o l u t i o n s . T h e a i m o f t h i s n e w e d i t i o n i s t o g i v e a n o v e r v i e w o f t h e c u r r e n t a n d

e me rg in g p ro bl e ms a nd w ha t c an b e d on e t o s ol ve t he m.

T hi s n ew e di ti on h as b ee n e xt en si ve ly u pd at ed a nd e xp an de d u si ng a

d i ff e re n t f r am e wo r k. I t n o w c o mp r is e s o f 3 1 c h ap t er s c l us t er e d i n to 5 d i st i nc t

parts, each dealing with a separate element of the water supply chain. Part I.

Introduction to water supply c o mp r i s es o f t h r e e i n t r o d u ct o r y c h a p te r s . T h erst

d ea ls w it h t he f un da me nt a ls o f t he w at er i nd us tr y: h ow m uc h w at er i s u se d;

wh at i s re qui re d by c on su me rs i n t er ms of q ua li ty ; a nd t he op era ti on,

m a na g em e nt a n d r e gu l at i on o f t h e w a te r u t il i t ie s . T h e r e ma i nd e r o f t h e c h ap t er

l o ok s a t t h e n e w m a na g e me n t a p pr o ac h es t o w a te r s u pp l y, i n p a rt i c ul a r w a te r

d e ma n d m a na g em e nt , a n d h o w w a te r c o ns e rv a ti o n i s b e co m in g a n i n te g ra l p a rt

o f s u st a in i ng f u tu r e s u pp l ie s . T h e s e co n d c h ap t er r e vi e ws h o w d r in k in g w a te r

s t an d ar d s a r e d e ve l o pe d a n d t h e r o le o f r i sk a s se s sm e nt i n t h at p r oc e ss . Wa t er

s af et y p la ns a re n ow t he b as is f or a ch ie vi ng g oo d q ua li ty a nd m ai nt ai ni ng

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s u p p l i e s a n d t h i s i s d i s c u s s e d i n d e t a i l . T h e c h a p t e r a l s o e x p l o r e s h o w g u i d e l i n e s

a nd s ta nd ar ds h av e c ha ng ed o ve r t he p as t 1 5 y ea rs . P ar t I c l os es w it h a q ui ck

o ve rv ie w o f t he p ro bl em s r el at in g t o d ri nk in g w at er q ua li ty, w he re t ho se

problems arise within the supply chain and where more information can be

a c ce s se d w i th i n t h is t e xt .

Part II. P ro b le m s w i t h t h e r es o ur ce e xa mi n es i n d ep th t he w at er q ua li ty

problems that arise within water resources due to natural and man-made

inu e n c es . C h a p te r 4 i s a b ri ef o ve rv ie w o f h ow q ua li ty v ar ie s d ue t o l an d u se

a nd n at ur a l g eo lo gy, c om pa ri ng s ur fa c e a nd g ro un d w at er s. T he r em ai ni n g

c ha pt e rs l oo k a t e ac h g ro up o f p ot en ti al c on ta mi na n ts i n t ur n e xa mi ni ng t he

s ou rc e , e ff ec ts o n c on su me rs a nd a pp ro pr i at e s ol ut i on s. T he re a re s ep ar at e

c h ap t er s d e al i n g w i th n i tr a t e a n d n i tr i te ; o r ga n ic m i cr o -p o ll u ta n ts i n cl u di n g

pesticides, industrial solvents and polycyclic aromatic hydrocarbons; endocrine-

d i sr u pt i ng ( o es t ro g en - mi m ic k in g ) c o mp o un d s, p h ar m ac e ut i ca l a n d p e rs o na lc a re p r od u ct s ; o d ou r a n d t a st e ; m e ta l s i n cl u di n g i r on , m a ng a ne s e, a r se n ic a n d

o th er h ea vy m et al s; h ar dn es s; a lg ae a nd a lg al t ox i ns ; r ad on a nd n on -r a do n

r a d i o nu c l i d es ; a n d p a t h og e n s .

Part III. P ro b l e m s a r i s i ng f r o m w a t e r t r ea t m e nt l o o k s a t h o w t h e v e r y a c t i o n

o f i m p r o v i n g w a t e r q u a l i t y c a n i t s e l f c a u s e s i g n ic a n t a e s t h e t i c a n d o c c a s i o n a l l y

h e al t h- r el a te d p r ob l em s . A f te r a b r ie f r e vi e w o f t r ea t m en t t e ch n ol o gy a n d h o w

problems arise, there are individual chapters dealing with the main issues:

o c cu l an t s s u ch a s a l um i ni u m a n d a c ry l am i de ; o d ou r a n d t a st e ; t h e c o nt e n ti o us

i ss ue o f u o r id a t i o n; d i s i nf e c t i on b y - pr o d u ct s i n c l u di n g t r i h al o m e t ha n e s ; a n d

pathogen removal. Part IV. P r ob l em s a r i si n g i n t h e d i st r i bu t io n n e tw o rk dealsspecic a l l y w i t h t h e t r a n s p o r t o f w a t e r f r o m t h e t r e a t m e n t p l a n t t o t h e c o n s u m e r ,

w h i c h c a n s e r i o u s l y a f f e c t w a t e r q u a l i t y . T h e d e s i g n a n d m a n a g e m e n t o f s e r v i c e

r e se r vo i rs , t h e m a in s a n d t h e i n di v id u al s e rv i ce p i pe t h at c o nn e ct s i n di v id u al

h ou se ho ld s t o t he n et wo rk a re e xp la in ed . C ha p te rs d ea li ng w it h a es th et ic

q ua li ty, a sb es to s, b it um en a nd c oa l- ta r l in in gs , t he r em ar ka bl e v ar ie ty o f

a n i m a l s , b o t h l a r g e a n d s m a l l , t h a t l i v e i n t h e n e t w o r k a n d o c c a s i o n a l l y p o p o u t

o f t he t ap, a nd n al ly t he p ro bl em s o f b iol m d e ve l op m en t a n d p a th o ge n s

w it hi n t he m ai ns a re a ll d ea lt w it h i n d et ai l. A ft er a ll t hi s t he w at er i s s ti l l v e r y

s u sc e pt i bl e t o c o nt a m in a ti o n f r om o u r o wn h o us e ho l d p l um b in g a n d s t or a ge

system. Part V. P ro bl em s i n h ou se ho ld p lu mb in g s ys te ms e x pl ai n s h ow

h ou se ho ld s ys te ms w or k a nd f ol l ow s w it h s pe ci a li st c ha pt e rs o n c or ro si on ,

i n cl u di n g l e ad c o nt a m in a ti o n, p a th o ge n s, s u ch a s Legionella and Mycobacter-

ium, a n d o t he r q u al i t y p r ob l em s .

Part VI. T h e w a t e r w e d r i n k d e a l s w i t h a n u m b e r o f c o n s u m e r - r e l a t e d i s s u e s .

The r st c ha pt er d ea ls w it h a lt er na ti ve s t o t ap w at er a nd i nc lu de s d et ai le d

s e c t i o n s o n b o t t l e d w a t e r , p o i n t - o f - u s e a n d p o i n t - o f - e n t r y t r e a t m e n t s y s t e m s a n d

o th er s ou rc es o f w at er s uc h a s r ai nw at e r h ar ve st in g a nd w at er r eu se . I s ai d a t

t he b eg i nn in g t ha t m uc h h as c ha ng ed i n t he w at er i nd us tr y i n t he d ev el op ed

w o rl d . W h at h a sn

t c ha ng e d i s t he n um be r o f p eo pl e f ac in g w at er s ca rc i ty i n

xiv Preface to the secon d edition


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d ev el op in g c ou nt ri es , l ea di ng t o p ov er ty, s ta rv at io n, s er io us i ll ne ss a nd

f r eq u en t ly d e at h . A f te r d e ca d es o f d e di c a te d a n d l i fe - sa v in g w or k b y a g en c ie s

s uc h a s Wa te rA id , t he s it ua ti on c on ti nu es t o w or se n, d ri ve n b y t he d ua l

problems of climate change and coni ct . Wa te r s ec ur it y i n t he t we nt y-rst

c e nt u ry l o ok s a t t h e p r ob l em o f t e rr o ri s m a n d e n s u ri n g w a te r i s p r ot e ct e d m o re

e f f e c t i v e l y f r o m d e l i b e r a t e o r a c c i d e n t a l c o n t a m i n a t i o n o r i n t e r r u p t i o n . T h e nal

c ha pt e r g iv es a n o ve rv i ew o f d ri nk i ng w at er q ua li t y a nd h ow c li ma te c ha ng e

w il l a ff ec t i t o ve r t he c om i ng d ec ad es .

E a ch c h ap t er i n t h e b o o k c o nc l ud e s w i th a b r ie f d i sc u ss i on o f t h e r e le v an c e

o f t he s pe cic p ro bl em s f or c on su me rs a nd s up pl ie rs a li ke . T he re a re a ls o a

n u mb e r o f a p pe n di c e s g i vi n g d r in k in g w a te r s t an d ar d s i n E u ro p e, U SA , a s w e ll

a s t he n ew W HO g ui de li ne s a nd m uc h e ls e.

I n t hi s t ex t I h av e a tt em pt ed t o p ro vi de a c oh es iv e a nd c om pr eh en si ve

i nt ro du ct i on t o t he w at er s up pl y i nd us tr y a nd t he s up pl y c ha in , w hi c h I h op ew il l b e e qu al l y u se fu l t o e ng in e er s, s ci en ti st s, m an ag er s a nd e ve n t he g en er al

c on su me rs w ho w an t s t o k no w m or e a bo ut t he w at er t he y d ri nk . T he t ex t h as

been designed to give you an integrated overview of drinking water quality and

t o a ct a s a r ef er en ce g ui de . I t s ho ul d b e u se d i n c on ju nc ti o n w it h t he I nt er ne t

w h er e v e ry d e ta i l ed i n fo r ma t io n c a n b e a c ce s se d a n d f o r t h at r e as o n k e y U RL s

h a ve b e en g i ve n w he r e a p pr o pr i at e i n t h e t e x t .

T h e r o y a l ti e s f r o m t h is t e xt h a ve b e en d o na t e d t o Wa t er Ai d (www.wateraid.

org.uk) , w hi ch i s a n i nt er na ti o na l n on -g ov e rn me nt al o rg an iz at i on ( NG O)

d ed ic at ed t o t he p ro vi si on o f s af e d ri nk in g w at er, s an it at io n a nd h yg ie ne

e d u c a t i o n t o t h e w o r l ds p o o r e s t c o m m u n i t i e s . A s y o u t u r n o n y o u r t a p a n d s a f ec l ea n w a te r p o ur s o u t, r e me m be r t h at t h is r e al l y i s s om e t hi n g v e ry s pe c i al a n d

t h a t i t h a s g i v e n u s t h e w o n d e r f u l s o c i e t y i n w h i c h w e l i v e t o d a y . I f y o u c a n h e l p

Wa te rA id i n g iv in g t hi s g if t t o o th er s t he n t ha nk y ou .

Preface to the seco nd ed itio n xv
http://www.wateraid.org.uk/http://www.wateraid.org.uk/http://www.wateraid.org.uk/http://www.wateraid.org.uk/


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Acknowledgements

I a m v e r y g r a t e f u l t o t h e v e r y m a n y p e o p l e w h o h a v e k i n d l y p r o v i d e d m e w i t h

i n fo r ma t i on . I w ou l d e s pe c ia l ly l i ke t o t h an k a n y p u bl i sh e rs o r o r ga n iz a ti o ns

w h o h a ve g i ve n t h ei r p e rm i ss i on t o r e pr o du c e, o r t o m o di f y, c o py r ig h t m a te r ia l

i n t hi s t ex t.

xvi


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P A R T I

INTRODUCTION TO WATER SUPPLY


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18.00

2 0 .0 0 e ac h d a y (F i gu r e 20.1). De ma nd i s g re at er d ur in g w ee ke nd s b ya bo ut 1 2% , w it h d em an d b ei ng h ig he r i n t he s um me r t ha n i n t he w in te r. I n t he

U K t h e t y pi c a l h o us e ho l d w a te r c o ns u mp t io n , t y pi c al h e re m e an i ng a f a mi l y o f

t wo a du lt s a nd t wo c hi l dr en , i s c ur re n tl y 5 10 l d1. T hi s i s e qu iv al en t t o a p er

c ap it a w at e r c on su mp ti o n r at e o f 1 501 8 0 l d1. L es s t ha n 20 % o f t he wa te r

s u pp l ie d i s c o ns u me d f o r d r in k in g o r f o od p r ep a ra t io n , w i th t o il e t u s h in g t h e

s i n g l e m a j o r u s e o f w a t e r ( T a b l e 1.2) . O w n e r s h i p o f c e r t a i n w h i t e g o o d s , w h i c h

h a s i n c r e a s e d d r a m a t i c a l l y o v e r t h e p a s t 2 0 y e a r s , h a s a n i m p o r t a n t i nu e n c e o n

w at er u sa ge . F or e xa mp le i n t he U K, 9 4% o f h ou se ho ld s o wn ed a w as hi ng -

m ac hi ne i n 2 00 3 c om pa re d t o j us t 7 9% i n 1 98 3. A s im il ar t re nd h as b ee n s ee n

w i t h d i s h w a s h e r o w n e r s h i p , w h i c h i s c u r r e n t l y 3 1 % i n t h e U K c o m p a r e d t o 5 %o ve r t he s am e p er io d. O n a v e ra ge a d is hw as he r a dd s a n e xt ra 6 l d1 t o t h e p e r

c a p i t a c o n s u m p t i o n , i n c r e a s i n g t h e o v e r a l l d e m a n d b y a b o u t 4 % . T a b l e 1.3 gives

s o m e i d e a o f t h e a m o u n t o f w a t e r s u c h a p p l i a n c e s u s e . A t t h e t o p o f t h e l i s t a r e

a u to m at i c w a sh i ng - ma c hi n es , w h ic h c a n u s e a s t ag g er i ng 1 0 0 l i tr e s e a ch t i me

t h e y a r e u s e d . A b a t h u s e s o n a v e r a g e 9 0 l i t r e s a t i m e c o m p a r e d w i t h a s h o w e r

t ha t c a n u s e a s l i t tl e a s 5 l m in1, a l t h o u g h t h i s d e p e n d s o n t h e s h o w e r h e a d u s e d .

F o r e x a m p l e , a p o w e r s h o w e r c a n u s e i n e x c e s s o f 1 7 l i t r e s p e r m i n u t e . G a r d e n

s pr in kl er s u se a bo ut a 1 00 0 l h1, w hi ch i s t he a ve ra ge d ai ly w at er u sa ge f or

s ev en o r e ig ht p eo pl e. C le ar ly n ot a ll t he p ub li c s up pl ie s a re u ti li ze d f or

Ta b l e 1 .2 Ty p ic a l c u rr en t d o me s t ic w a te r u s e i n E n gl a nd a n d Wa l es

Use % Use %

Toilet 35 Washb asin 8

Kitchen sink 15 Outside use 6

Bath 15 Sho wer 5

Wash ing -machin e 12 Dishwasher 4

Ta b l e 1 .3 A ve ra ge w at er u se o f a r an ge o f a ct iv it i es a nd a pp li an ce s

Pu rp ose o f water u se Frequency Litres

Co o kin g , d rin kin g , wash in g -u p

a n d p e r s on a l h y g ie n e

per person per day 27

Bath one 90

Sh ower one 20

To ilet one 69a

Automatic was hin g-machin e one 100

Dish washin g machine o ne 50

Hosepipe/sprinkler per minu te 18

a M o d e r n c i s t e r n s n o w u s e 4 l i t r e s , o r m o r e c o m m o n l y 6 l i t r e s , c o m p a r e d t o

9 l i tr e s i n o ld e r s y st e ms .

1.2 Water co nsumption 5


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d om es ti c p ur po se s. T hi s i s i ll us tr at ed b y t he a na ly si s o f d ai ly w at er u sa ge i n

19845 by the former Severn and Trent Water Authori ty. Of the total

1 942 Ml d1 s u pp l ie d e a ch d a y, 8 4 0 M l w a s u s ed f o r d o m es t ic p u rp o se s , 5 3 0 M l

f o r i n du s tr i al , 5 0 M l f o r a g r i c ul t ur a l p u rp o se s a n d a r e ma r ka b le 5 2 2 M l ( 2 6. 9 %)

w a s l o st e v er y d a y t h ro u gh a l e ak y d i st r i bu t io n s y st e m ( Ta b le 1.4).

L osse s f rom l ea ks a re a wi de spr ea d p ro bl em a s wa te r m ai ns no t o nl y

d e t e r i o r a t e w i t h a g e , b u t a r e o f t e n d a m a g e d b y h e a v y v e h i c l e s , b u i l d i n g w o r k o r

s u bs i de n ce . L e ak a ge c o nt r ol i s a v i ta l m e th o d o f c o ns e rv i ng w a te r. D e te c t in g

a n d r e pa i ri n g l e ak s i s b o th l a bo u r i n te n si v e a n d t i me c o ns u mi n g, w h ic h m e an s

t h a t i t i s v e r y e x p e n s i v e . H o w e v e r , i f l e a k s a r e n o t c o n t r o l l e d t h e n w a t e r d e m a n d

w il l e sc al at e, wi th m os t o f t he e xt ra d em an d s ee pi ng a wa y i nt o t he g ro un d

i n st e ad o f m a k i n g i t s w a y t o t h e c o n s um e r. I n E n g l an d a n d Wa l es 3 6 08 M l o f t h e

1 5 3 78 M l o f t re at ed w at er s up pl ie d e ac h d ay w as l os t d ur in g 2 00 4/ 5 t hr ou gh

l ea ka ge , 2 58 4 M l d1 f ro m t he d is tr ib ut io n m ai ns ( 17 % o f t ot al i np ut ) a nd

1 02 4 Ml d1 f ro m s up pl y p ip es ( 7% o f t ot a l i np ut ) . T he c ur re n t l ea ka ge r at e i s

Ta b l e 1 .4 E s ti m at e d d a il y u s e o f w a te r s u pp l ie d b y t h e f o r m e r S e v e r n a n d Tr en t

W a t e r A u t h o r i t y d u r i n g 1 9 8 45 . A d a p t e d f r o m A r c h i b a l d ( 1986) with permission

from the Economic and Social Research Council

Amoun t used Amoun t used

T ype o f use (Ml d1) Purpo se (Ml d1)

Domestic 840 Basic 288

Toilet flu shing 242

Bathing 155

Was hing -m ac hin e 1 14

External use 27

Luxury app liances 14

I n d us t r i al a n d

c ommercial 530 Processin g 256

Do mestic 153

Co oling: direct 77

Co oling: recycled 44

Agricultural 50 Livestock 35

Do mestic 10

Protected crops 3

Outd oor irrigation 2

Unac counted fo r 522 Distribu tion system 287

Co n su mers service

pipes

167

Trunk main s 52

Service reservoirs 16

T otal 1942

6 T he water bus iness


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3 3% l ow er t ha n t he p ea k l ea ka ge r at es r ep or te d i n 1 99 4/ 5, b ut h as r em ai ne d

static each year since 1997/8 at bet ween 22% and 25% despite a huge

i n v e s t m e n t b y t h e w a t e r c o m p a n i e s i n r e p a i r s a n d r e p l a c e m e n t t o t h e d i s t r i b u t i o n

n e t w o r k e a c h y e a r ( F i g u r e 1.1) . C u r r e n t l y , 2 4 % o f a l l w a t e r t r e a t e d i s b e i n g l o s t

d u e t o l e ak a ge .

S t u d i e s o f w a t e r u s a g e a r e v e r y d i f c u l t t o c a r r y o u t , a s i n d i v i d u a l u s e o f w a t e r

i s s o v ar ia bl e . A ct ua l a v er ag e c on su mp ti on v al ue s m ay a ls o h id e w at er l os t b y

l e a ka g e w i th i n t h e h o us e ho l d p l u mb i n g s y s t e m f o r e x a mp l e . T h e N a ti o na l Wa t e r C ou nc i l (1982) c ar ri ed o ut a d et ai le d s tu dy o f w at er u sa ge a nd f ou nd t ha t t he

a c t ua l a v e ra g e c o n su m pt i on l e ve l s w e re s l ig h tl y l o we r t h a n t h o se c a l cu l a te d b y

t h e c o m p a n i e s a t t h a t t i m e ( T a b l e 1.5) . T h i s a n d s u b s e q u e n t s t u d i e s o n t h e p a t t e r n

o f d om es ti c w at er u sa ge h av e s ho wn t ha t p er c ap it a c on su mp ti on d ec re as es

s l i g h t l y w i t h a n i n c r e a s e i n h o u s e h o l d s i z e , a n d t h a t s o c i a l g r o u p i n g s a l s o h a v e a n

inu en ce , w it h S oc ia l G ro up A u si ng a bo ut 5 0 l d1 m or e t ha n S oc ia l G ro up E

(Bailey et al ., 1986) ( Ta b le 1.5) . I t w as a ls o s ho wn t ha t t he d ai ly v ol um e o f

w a te r c o ns u me d p e r h o us e ho l d f o r n o n- p ot a bl e p u rp o se s i s d e pe n de n t o n t h e

s iz e o f t he h ou se ho ld . S o o n a n at io na l b as is a bo ut 3 % o f t he t ot al v ol um e o f

d om es ti c w at er c on su me d e ac h d ay i s u se d f or p ot ab le p ur po se s, w hi ch i se q u i v a l e n t t o a b o u t 1 0 l i t r e s f o r t h e a v e r a g e h o u s e h o l d . I n t e r e s t i n g l y , 2 5 % o f t h e

r s t d r a w s o f w a t e r t a k e n f r o m t h e s y s t e m e a c h d a y a r e f o r p o t a b l e p u r p o s e s , a

h ab it t ha t m ay h av e s ig nic a nt c o ns e qu e nc e s i n t h os e a r ea s w he r e t h e w a t e r i s

c o rr o si v e a n d l e ad o r g a lv a ni z ed p l um b in g i s u s ed ( C ha p te r 27).

1.3 Acceptable water quality

Wa te r r ap id ly a bs or bs b ot h n at ur al a nd m an -m ad e s ub st an ce s, g en er al l y

m ak in g t he w at er u ns ui ta bl e f or d ri nk in g w it ho ut s om e f or m o f t re at me nt .

6000Losses from supply pipes

Losses from distribution mains

5000

4000

3000

megalitreslostdaily

2000

1000

0

19923 19945 19967 19989 20001 20023 20045

Figure 1.1 W a t e r l e a ka g e

r e p o rt e d i n E n g l an d a n d

W a l es d u r i ng t h e p e r i o d

1 9 9 2/ 3 t o 2 0 0 4/ 5 . A d a pt e d

f r om D e fr a (2006) w it hp e r mi s s i on f r o m D e f ra .

1.3 Acc eptable water quality 7


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I mp or ta nt c at eg or ie s o f s ub st an ce s t ha t c an b e c on si de re d u nd es ir ab le i n

e x c e ss a r e :

1. Colour . T h i s i s d u e t o t h e p r e s e n c e o f d i s s o l v e d o r g a n i c m a t t e r f r o m p e a t y s o i l s , o r t h e

m i ne r al s a lt s o f i r on a n d m a ng a n es e .

2. S u s p e nd e d m a t t e r . T h i s i s n e m i n e r a l a n d p l a n t m a t e r i a l t h a t i s u n a b l e t o s e t t l e o u t o f

s o l u ti o n u n d e r t h e p r e v a il i n g c o n d i ti o n s .

3. Turbidity. T h is i s a m e as u re o f t h e c l a r it y, o r t r an s pa r en c y, o f t h e w a t e r. C l ou d in e ss

c an b e c a us ed b y n um er ou s f ac to rs s uc h a s n e m i ne r al p a rt i cl e s i n s u sp e n si o n, h i gh

bacteria concentrations, or even n e b u b bl e s d u e t o o v e r- a er a ti o n o f t h e w a t e r.

4. Pathogens. T he se c an b e v ir us es , b ac te ri a, p ro to zo a o r o th e r t yp es o f p at ho ge ni c

o rg an is m t ha t c an a dv er se ly a ff ec t t he h ea lt h o f t he c on su me r. T he y c a n a ri se f ro m

a n im a l o r h u ma n w a st e s c o nt a mi n at i ng t h e w a te r r e so u rc e .

5. Hardness. E x ce s si v e a n d e x tr e me l y l o w h a rd n e ss a r e e q ua l ly u n de s ir a bl e . E x ce s si v e

h ar dn es s a ri se s m ai nl y f ro m g ro un d wa te r r es ou rc es w he re as v er y s of t w at er s a re

c h a r a ct e r i st i c o f s o m e u p l a n d c a t c h m e n ts .

6. T a s te a n d o d o u r . U n p l e a s a n t t a s t e s a n d o d o u r s a r e d u e t o a v a r i e t y o f r e a s o n s s u c h a s

c o nt a mi n at i on b y w a st e wa t er s , e x ce s si v e c o nc e nt r at i on o f c e rt a in c h e mi c al s s u ch a s

i r o n , m a n g a n e s e o r a l u m i n i u m , d e c a y i n g v e g e t a t i o n , s t a g n a n t c o n d i t i o n s d u e t o a l a c k

o f o xy ge n i n t he w at er, o r t he p re se n ce o f c er ta in a lg ae .

Ta b l e 1 .5 C o mp a r is o n o f a v er a ge w a te r c o ns u mp t io n p e r p e rs o n i n t h re e w a te r

c o mp a ny a re a s w i t h r es p ec t t o h o us e ho l d s i ze a n d s o ci o -e c on o mi c g ro u p

Adapted from National Water Council (1982) with permission from the National

Wa t e r C o u n c il

A v er a ge w a te r c o ns u mp ti o n ( 1 d1)

South West Severn Trent Thames

H o u se h o ld s i z e

1 126 116 136

2 124 118 151

3 118 109 123

4 110 92 116

5 103 96 103

6 97 75 977 92 69 64

S o c ia l g r o up

A 138 126 134

B 124 117 126

C1 122 100 124

C2 111 93 113

D 103 93 102

E 86 76 94



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7. H a r m fu l c h e m i ca l s. T h e r e i s a w i d e r a n g e o f t o x i c a n d h a r m f u l o r g a n i c a n d i n o r g a n i c

c om po un ds t ha t c an o cc u r i n w at er r es ou rc es . T he se a re a bs or be d f ro m t he s oi l o r

o c cu r d u e t o c o nt a mi n at i on f r om s e wa g e o r i n du s tr i al w a st e wa t er s .

Wa te r t re at me n t a nd d is tr ib ut io n i s t he p ro ce ss b y w hi c h w at er i s t ak en f ro mw at er r es ou rc es , m ad e s ui t ab le f or u se a nd t he n t ra ns po rt ed t o t he c on su me r.

T h i s i s t h e f i r s t h a l f o f t h e h u m a n o r u r b a n w a t e r c y c l e , b e f o r e w a t e r i s a c t u a l l y

u se d b y t he c on su me r ( Fi gu re 1.2). The second half of the cycle is the

c o ll e ct i o n, t r ea t me n t a n d d i sp o sa l o f u s ed w a te r ( s ew a ge ) ( G ra y, 2004).

T he o bj ec ti ve o f w at er t re at me nt i s t o p ro du ce a n a de qu at e a nd c on ti nu ou s

s u pp l y o f w a te r t h at i s c h em i c al l y, b a ct e ri o l og i ca l ly a n d a e st h et i c al l y p l ea s in g .

M o re s pe c i fi c al l y, w a te r t r ea t m en t m u st p r od u ce w a te r t h at i s :

1. Palatable t h at i s , h a s n o u n pl e as a nt t a st e ;

2. Safe

it s ho ul d n o t c on ta in a ny p at ho ge ni c o rg a ni sm o r c he mi ca l t ha t c ou ld b eh a rm f ul t o t h e c o ns u me r ;

3. Clear b e f r ee f r om s u sp e n de d m a tt e r a n d t u rb i di t y;

4. C o l o u r l e s s a n d o d o u r le s s b e a e st h et i c t o d r in k ;

5. R e a s o na b l y s o f t t o a l l o w c o n s u m e r s t o w a s h c l o t h e s , d i s h e s a n d t h e m s e l v e s w i t h o u t

e x ce s si v e u s e o f d e te r ge n ts o r s o ap s ;

6. Non-corrosive w a te r s h ou l d n o t b e c o rr o si v e t o p i pe w or k o r e n co u ra g e l e ac h in g o f

m e ta l s f r om p i pe s o r t a nk s ;

7. L o w i n o rg a ni c c o n te n t a h i gh o r ga n ic c o nt e nt w i ll e n co u ra g e u n wa n te d b i ol o gi c al

g ro wt h i n p ip es o r s to ra ge t an ks , w hi ch c a n a ff ec t t he q ua li ty o f t he w at er s up p li ed .

W it h t h e p u bl i ca t io n o f d r in k in g w a te r s t an d ar d s s u ch a s t h e E u ro p ea n U ni o n

D ri nk in g Wa te r D ir ec ti ve ( 98 /8 3/ EE C) ( Ap pe nd ix 1 ) a nd t he S af e D ri nk in g

W a t e r A c t ( 1 9 7 4 ) i n t h e U S A , w h i c h h a s g i v e n r i s e t o t h e N a t i o n a l P r i m a r y a n d

S e co n da r y D r in k in g Wa t er S t an d ar d s ( A pp e nd i x 2 ) , w a te r m u st c o nf o rm t o t h e

s t an d ar d s l a i d d o wn f o r a l a rg e n u mb e r o f d i ve r se p a ra m et e r s. I n E n gl a nd a n d

Wa le s, f or e xa mp le , t he E ur op ea n D ir ec ti ve i s e nf or c ed b y t he Wa te r S up pl y

TREATMENTWORKS

WATER RESOURCES AND TREATMENT DISTRIBUTION DEMAND SEWERAGESEWAGE TREATMENT

TREATMENTWORKS

WATERTOWER

BOREHOLE

SERVICERESERVOIR

IMPOUNDINGRESERVOIR

RIVER

RIVER

Figure 1.2 Schematic

d i a g ra m s h o w in g t h e r o l e

o f t h e w a t e r c o m p an i es i n

s u pp l yi n g w a te r t o t h e

c o n s um e r a n ds u b s eq u e n tl y t r e at i n g i t

b e fo r e r e t u rn i ng i t t o t h e

hydrological cycle

(Latham, 1990) . D e m an d s

s h o wn a r e i n d u st r i al ,

d o m es t i c , fi r e - fig h t i ng a n d

l e a ka g e . A d a pt e d w i t h

p e r mi s s io n f r o m t h e

C h a rt e r ed I n s t it u t io n o f

W a t er a n d E n v ir o n me n t al

Management.

1.3 Acc eptable water quality 9


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Ta b l e 1 .6 L i st o f t he 1 0 w at er a nd s ew er ag e c om pa ni es a nd 1 6 w at er o nl y

c o mp a ni e s s u pp l yi n g d r in k i ng w a te r i n E n gl a nd a n d Wa l es a n d t h ei r w e b

addresses

Water and sewerage companies

A n g li a n W a t er S e r vi c e s L t d www.an g lian water.co .u k

D w r C y m ru C y f yn g e di g ( W e ls h W a t er ) www.d wrcymru .co .u k

N o r th u m br i a n W a t er L t d www.n wl.co .u k

S ev e rn T r en t W at e r L t d www.stwater.co .u k

S ou t h W es t W a te r L t d www.so u th westwater.co .u k

S o u th e r n W a t er S e r vi c e s L t d www.so u th ern water.co .u k

T h am e s W a t er U t i li t i es L t d www.th ameswater.co .u k

U n i te d U t i li t i e s W a t e r P l c www.u n ited u tilities.co m

W e s se x W a t er S e r vi c e s L t d www.wessexwater.co .u k

Y o r ks h i r e W a t e r S e r vi c e s L t d www.yo rksh irewater.co mWater only companies

A l b io n W a t er L t d www.alb io n water.co .u k

B o u rn e m ou t h & W e s t H a m ps h i re

W a t er P l c

www.b wh water.co .u k

B r i s to l W a t er P l c www.b risto lwater.co .u k

C a m br i d ge W a t er C o m pa n y P l c www.camb rid g e-water.co .u k

C h o ld e r to n a n d D i s t ri c t W a t er

C o m pa n y L t d

www.water-g u id e.o rg .u k/

ch o ld erto n -water.h tml

D e e V al l ey W at e r P lc www.deevalleygroup.com/

DVW/DVW.htm

E s se x & S uf f ol k W a te r ( N ow

p ar t o f N or t hu m br i a W a te r L t d)

www.eswater.co .u k

F o l ke s t on e & D o v er W a t er

S e r vi c e s L t d

www.fd ws.co .u k

H a rt l ep oo l W at e r P l c ( N ow p a rt

o f A ng l ia n W a te r S e rv ic e s L t d)

www.h artlep o o lwater.co .u k

M i d K e n t W at e r P l c www.mid ken twater.co .u k

P o r ts m o ut h W a t er P l c www.p o rtsmo u th water.co .u k

S ou t h E as t W a te r P l c www.so u th eastwater.co .u k

S o u th S t a ff o r ds h i r e W a t e r P l c www.so u th -staffs-water.co .

u kS ut t on a n d E as t S u rr e y W a te r

P lc

www.waterp lc.co m

T e nd r i ng H u n dr e d W a t er

S e r vi c e s L t d

www.th ws.co .u k

T h r ee V a l le y s W a t er P l c www.3valleys.co .u k

1.4 Water utilities 11
http://www.anglianwater.co.uk/http://www.dwrcymru.co.uk/http://www.nwl.co.uk/http://www.stwater.co.uk/http://www.southwestwater.co.uk/http://www.southernwater.co.uk/http://www.thameswater.co.uk/http://www.unitedutilities.com/http://www.wessexwater.co.uk/http://www.yorkshirewater.com/http://www.albionwater.co.uk/http://www.bwhwater.co.uk/http://www.bristolwater.co.uk/http://www.cambridge-water.co.uk/http://www.water-guide.org.uk/http://localhost/var/www/apps/conversion/tmp/scratch_5/cholderton-water.htmlhttp://www.deevalleygroup.com/http://localhost/var/www/apps/conversion/tmp/scratch_5/DVW/DVW.htmhttp://www.eswater.co.uk/http://www.fdws.co.uk/http://www.hartlepoolwater.co.uk/http://www.midkentwater.co.uk/http://www.portsmouthwater.co.uk/http://www.southeastwater.co.uk/http://www.south-staffs-water.co.uk/http://www.south-staffs-water.co.uk/http://www.waterplc.com/http://www.thws.co.uk/http://www.3valleys.co.uk/http://www.3valleys.co.uk/http://www.thws.co.uk/http://www.waterplc.com/http://www.south-staffs-water.co.uk/http://www.south-staffs-water.co.uk/http://www.southeastwater.co.uk/http://www.portsmouthwater.co.uk/http://www.midkentwater.co.uk/http://www.hartlepoolwater.co.uk/http://www.fdws.co.uk/http://www.eswater.co.uk/http://localhost/var/www/apps/conversion/tmp/scratch_5/DVW/DVW.htmhttp://www.deevalleygroup.com/http://localhost/var/www/apps/conversion/tmp/scratch_5/cholderton-water.htmlhttp://www.water-guide.org.uk/http://www.cambridge-water.co.uk/http://www.bristolwater.co.uk/http://www.bwhwater.co.uk/http://www.albionwater.co.uk/http://www.yorkshirewater.com/http://www.wessexwater.co.uk/http://www.unitedutilities.com/http://www.thameswater.co.uk/http://www.southernwater.co.uk/http://www.southwestwater.co.uk/http://www.stwater.co.uk/http://www.nwl.co.uk/http://www.dwrcymru.co.uk/http://www.anglianwater.co.uk/


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T h er e a r e t h re e f o rm s o f r e gu l a ti o n o n w a te r u t il i t ie s , e c on o mi c , q u al i ty a n d

e nv ir on me nt al . E co no mi c a nd n an ci al r eg ul at io n d ep en ds o n w he th er

c o mp a ni e s a r e p r iv a te l y o r p u bl i cl y o w ne d , w he r e as q u al i ty a n d e n vi r on m en t al

r eg ul at io n a re i mp os ed o n a ll w at er u ti li ti es b y t he i mp le me nt at io n o f E C

D i r e c t i v e s o r o t h e r l e g i s l a t i o n , a l t h o u g h t h e r a t e o f i m p l e m e n t a t i o n a n d t h e e x a c t

n a tu r e o f t h ei r i m pl e me n t at i on m a y d i ff e r s l ig h tl y.

S o whi le l arg el y p ri va ti ze d, UK wa te r u ti li ti es a re r egu la te d b y t he

g ov er nm en t t hr ou gh l eg is la ti on a nd s ta nd ar ds , a nd i n t hr ee k ey a re as b y

g o v e r n m e n t - a p p o i n t e d o r g a n i z a t i o n s . I n E n g l a n d a n d W a l e s t h e W a t e r A c t 1 9 8 9

e na bl ed p ri va ti za ti on o f t he wa te r i ndu st ry, a nd t hr ou gh i ts nu me rou s

a me nd me nt s m ak es t he p ri nc ip al r eg ul at or s t he S ec re ta ry o f S ta te , t he Wa te r

S e r v ic e s R e g u l at i o n A u t ho r i t y a n d t h e E n v i ro n m e nt A g e nc y.

T he w at er u ti li ti es i n E ng la nd a nd Wa le s a re d if fe re nt t o o th er b us in es s

s ec to rs i n t ha t t he y d o n ot h av e t o c om pe t e f or d om es ti c c us to me rs a nd o nl yc o m p e t e i n a v e r y l i m i t e d w a y f o r i n d u s t r i a l c u s t o m e r s . F o r t h a t r e a s o n t h e p r i c e

t h e y c a n c h a r g e f o r w a t e r i s r e g u l a t e d t o p r o t e c t c u s t o m e r s f r o m b e i n g e x p l o i t e d .

T hi s f un ct io n i s c ar ri ed o ut b y t he Wa te r S er vi ce s R eg ul at i on A ut ho ri t y i n

E n gl a nd a n d Wa l es w ho i s c h ar g ed w i th p r ot e ct i n g c u st o me r s i n t e r es t s w h i l e

e n su r in g t h at t h e p r iv a te l y o w ne d w a te r c o mp a ni e s c a rr y o u t a n d n a n c e t h e i r

f u n c t i o n s p r o p e r l y . T h e W a t e r S e r v i c e s R e g u l a t i o n A u t h o r i t y r e p l a c e d t h e O f ce

o f Wa te r S er vi c es ( Of wa t ) a s t he G ov er nm en t s s ta tu to r y w at ch do g (www.

ofwat.gov.uk ) i n A p r i l 2 0 0 6 i n o r d e r t o b r i n g i t i n l i n e w i t h t h e o t h e r e c o n o m i c

r e gu l at o rs , a l th o ug h t h e a c ro n ym O f wa t h a s b e en r e ta i ne d . I t i s t o t h is a u th o ri t y

t h a t c o n s u m e r s u l t i m a t e l y t a k e t h e i r c o m p l a i n t s a n d p r o b l e m s r e l a t i n g t o p r i c i n ga n d s t a n d a r d s o f s e r v i c e w h e n t h e y h a v e f a i l e d t o o b t a i n s a t i s f a c t i o n f r o m e i t h e r

t h e w a te r c o mp a ny i t se l f o r t h ro u gh t h e C o ns u me r C o un c il f o r Wa t er , w hi c h i s

a n i n d e p e n d e n t o r g a n i z a t i o n t h a t r e p r e s e n t s c u s t o m e r s i n t e r e s t s . T h e c o s t o f t h i s

i s b or ne b y t he l ic en ce f ee p ai d b y t he w at e r s er vi ce c om pa ni es a nd s ta tu to ry

w a te r c o mp a ni e s ( k no w n a s a p po i nt e es ) i n E n gl a nd a n d Wa l es .

M o re s p ec ic a ll y, t h e Wa t er S e rv i ce s R e gu l at i on A u th o ri t y, i n c o ns u lt a ti o n

w i th t h e S e cr e ta r y o f S t at e f o r E n vi r on m en t , F o od a n d R u ra l A f fa i rs , t h e We l sh

A ss em bl y a nd o th er i nt e re st ed g ro up s, h as t he p ri ma ry d ut y t o ( 1) e ns ur e t ha t

w a t e r a n d s e w e r a g e f u n c t i o n s a r e p r o p e r l y c a r r i e d o u t i n E n g l a n d a n d W a l e s a n d

( 2 ) e n s u re t h at t h e w a t e r u n d e rt a ke r s a r e a b le t o n a nc e t h e p r op e r o p er a ti o n o f

t h es e f u nc t io n s b y s e cu r in g r e as o na b le r e tu r ns o n t h ei r c a pi t al . S ub j ec t t o t h es e

primary duties the Authority is also responsible to: (i) protect the interests of

c us to me rs a nd p ot en ti al c us to me rs i n r es pe c t o f c ha rg es ( ha vi ng p ar ti cu la r

r eg ar d t o t he i nt er es ts o f c us to me rs i n r ur al a re as a nd t o e ns ur e t ha t i n xing

c h ar g es t h er e i s n o u n du e p r ef e re n ce t o wa r ds , o r u n du e d i sc r im i na t io n a g ai n st ,

c us to me rs o r p ot en ti al c us to me rs ); ( ii ) p ro te ct t he i nt e re st s o f c us to me rs a nd

potential customers in respect of other terms of supply, the quality of services

( t ak i ng i n to a c co u nt i n p a rt i c ul a r t h os e w h o a r e d i sa b l ed o r o f p e ns i on a bl e a g e)

a nd t he b en e

t s t ha t c ou ld b e s ec ur ed f ro m t he p ro ce ed s o f t he d is po sa l o f

http://www.ofwat.gov.uk/http://www.ofwat.gov.uk/http://www.ofwat.gov.uk/http://www.ofwat.gov.uk/


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c er ta in l an d t ra ns fe rr ed t o c om pa ni es w he n t he f or me r R eg io na l Wa te r

A u th o ri t i es w e re p r iv a t iz e d; ( i ii ) p r om o te e c on o my a n d e f c ie nc y o n t he p ar t

o f ut il it ies i n t he c ar ryi ng o ut o f t he wa te r a nd se we ra ge fu nct io ns i n a

s u st a in a bl e m a nn e r; a n d ( i v) f a ci l it a t e e f fe c ti v e c o mp e ti t io n b e tw e en p e rs o ns

h ol di n g o r s ee ki n g a pp oi nt me nt s u nd er t he Wa te r A ct a s w at er o r s ew er ag e

utilities.

To a c t a s a b u ff e r b e t w ee n c o ns u me r s w i th c o mp l a in t s a n d O fw a t i t se l f, t h e

Consumer Cou ncil for Water (www.ccwa ter.org.uk) i s a n i nd ep e n de nt g ro up

t ha t d ea ls w it h c on su me r c om pl ai nt s a t a p er so na l l ev el w he n t he y h av e n ot

r e c e i v e d s a t i s f a c t i o n f r o m t h e C o m p a n y c o m p l a i n t s p r o c e d u r e . O f w a t d e a l s w i t h

c om pl a in ts o f a m or e g en er al n at ur e i n r el at i on t o p ri ci ng , c om pe t it io n a nd

l e ve l s o f s e rv i ce p r ov i de d b y c o mp a ni e s.

S in ce 1 S ep te mb er 1 98 9 a ll t he w at er u ti li ti es i n E ng la nd a nd Wa le s h av e

o pe ra t ed u nd er t he t er ms o f a n i nd iv id ua l a pp oi nt me nt , w hi ch i s i n e ss en c e ak i nd o f o p er a to r s l ic en ce . T he t er ms o f t he a pp oi nt m en t s et o ut t he m ax im um

c h a r g e i n c r e a s e (K) f o r a l l r e g u l a t e d s e r v i c e s , m a i n l y w a t e r s u p p l y a n d s e w e r a g e

c ha rg es . A ls o d en ed a re t he c ir cu ms ta nc es u nd er w hi ch u nf or es ee n o r

previously unquantia b le o b li g at i on s p l ac e d o n t h e c o mp a ni e s m a y b e e l ig i bl e

f or c os ts t o b e p as se d o nt o c us to me rs , a p ro ce ss k no wn a s c o s t p a ss t h ro u gh.

T h e Wa t er A c t e n ab l es O fw a t t o m o ni t o r s t an d ar d s o f c u st o me r s e rv i ce , w h ic h

i nc lu de s t he a ss es sm en t o f t he s ta te o f u nd er gr ou nd a ss et s s uc h a s m ai ns a nd

s ew er s t o e ns ur e t ha t t he se a re p ro te c te d a ga in st p ro gr es si ve d et er io ra ti on .

A m on g t h e m a jo r n a nc i al p r ob l e ms f a ci n g t h e w a te r s e rv i c e c o mp a ni e s i s t h e

r eh ab il it at io n o f t ho us an ds o f k il om et r es o f o ld a nd l ea ki ng w at er m ai n s a nds e we r s, a n d t h e r e pl a ce m en t o f l e ad s e rv i ce p i pe s .

T he Wa te r A ct r eq ui re s e ac h w at er c om pa ny t o d ev el op a nd m ai nt ai n a n

efc ie nt a nd e co no mi c s ys te m o f w at er s up pl y w it hi n i ts a re a. I t m us t a ls o

e ns ur e t ha t a ll s uc h a rr an ge m en ts h av e b ee n m ad e f or p ro vi di ng s up pl ie s o f

w at er t o p re mi se s i n i ts a re a, m ak i ng s uc h s up pl ie s a va il a bl e t o p eo pl e w ho

d em an d t he m a nd f or m ai n ta in in g, i mp os in g a nd e xt en di ng i ts d is tr ib ut io n

s y st e m a s n e ce s sa r y, t o e n ab l e i t t o m e et i t s w a te r s u pp l y o b li g at i on .

I n S co tl a nd t he Wa te r I nd us t ry C om mi ss io ne r h as t he s am e f un ct io n a s

O fw at i n r el at io n t o S co tt is h Wa te r a nd o ve rs ee s c ha rg in g p ol ic y a nd s er vi ce

s t a n d a r d s . T h e C o m m i s s i o n e r i s s u p p o r t e d b y v e r e g i o n a l p a n e l s t h a t r e p r e s e n t

t he v ie ws o f c us to me rs . Wa te r s er vi ce s i n N or th er n I re l an d a re c on tr ol le d

c e nt r al l y b y g o ve r nm e nt w h o a l so s e t c h ar g es .

T h e D r in k in g Wa t er I n sp e ct o ra t e ( D WI ) (www.dwi.gov.uk) w as f or me d a t

t he b eg in ni ng o f J an ua ry 1 99 0 a nd h as n in e m ai n t as ks : ( 1) To c ar ry o ut

t e c h ni c a l a u d it s o f w a t e r c o m p a ni e s. T h i s i s a s y s t e m u s e d b y t h e D W I t o c h e c k

t h at w a te r s u pp l y c o mp a ni e s a r e c o mp l yi n g w i th t h ei r s t at u to r y o b li g at i on s a n d

w he th er t he y a re f ol lo wi ng g oo d p ra ct ic e. T he re a re t hr ee e le me nt s t o t hi s

t e ch n ic a l a u di t . F i rs t ly a n a n nu a l a s se s sm e nt b a se d o n i n fo r ma t i on p r ov i de d b y

t he c om pa ni es o f t he q ua li ty o f w at er i n e ac h s up pl y z on e, w at er t re at me nt

http://www.ccwa%20ter.org.uk/http://www.dwi.gov.uk/http://www.ccwa%20ter.org.uk/http://www.dwi.gov.uk/


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w o r k s a n d s e r v i c e r e s e r v o i r s , c o m p l i a n c e w i t h s a m p l i n g a n d o t h e r r e q u i r e m e n t s

a n d t h e p r o g r e s s m a d e o n i m p r o v e m e n t p r o g r a m m e s . T h e s e c o n d e l e m e n t i s t h e

i n sp e ct i on o f i n di v id u al c o mp a ni e s c o ve r in g a l l t h e a b ov e p o in t s a t t h e t i me o f

t he i ns pe ct io n, b ut a ls o a n a ss es sm en t o f t he q ua li ty a nd a cc ur ac y o f t he

i nf or ma t io n c ol le ct ed b y t he c om pa ny. T he t hi rd a nd n al e le me nt i s i nt e ri m

c h ec k s, w hi c h a r e m a de b a se d o n t h e i n fo r ma t i on p r ov i de d b y t h e c o mp a ni e s.

(2) T o i n s t i g a t e a c t i o n a s n e c e s s a r y t o s e c u r e o r f a c i l i t a t e c o m p l i a n c e w i t h l e g a l

requirements. (3) To i n ve s t ig a te i n ci d en t s t h at a d ve r se l y a f fe c t w a te r q u al i ty.

(4) To a d vi s e t h e S e cr et a ry o f S t at e i n t h e p ro s ec u ti o n o f w a te r c o mp a ni e s who

h av e s up pl ie d w at er f ou nd t o b e u nt f o r h u ma n c o ns u mp t io n . ( 5 ) To p r ov i d e

t e c h ni c a l a n d s c i e n tic a dv ic e t o M in is t er s a nd O f c i al s o f t h e D e p a r tm e nt f o r

Environment, Food and Rural Affairs (Defra) and Welsh Ofc e o n d ri nk in g

w a te r i s su e s. (6) To a ss es s a nd re sp on d t o c on su me r c om pl ai n ts w he n l oc al

procedures have been exhausted. A lm os t a ll o f t he se p ro bl e ms a re r es ol v ed b yr e f e r r i n g t h e c o m p l a i n t b a c k t o t h e w a t e r s u p p l y c o m p a n y c o n c e r n e d , r e q u e s t i n g

t he m t o i nv es ti ga te t he m at te r a nd r ep or t b ac k t o t he D WI . T he D WI m ay a ls o

a s k t h e l o c a l e n v i r o n m e n t a l h e a l t h o f c e r t o i n v e s t i g a t e t h e m a t t e r a n d t o r e p o r t

back. The DWI also works closely with Ofwat and will investigate and liaise

w i th t h em o n c o mp l a in t s. O fw a t r e ce i v es c o mp l ai n ts f r om C o ns u me r C o un c il

f or Wa te r a nd t he se m ay b e p as se d o n t o t he DW I. ( 7) To i d en t if y a n d a s se s s

n e w i s s u e s o r h a z a r d s r e l a t i n g t o d r i n k i n g w a t e r q u a l i t y a n d i n i t i a t e r e s e a r c h a s

required . ( 8 ) To a s se s s c h em i c al s a n d m a te r i al s u s ed i n c o nn e ct i o n w i th w a te r

supplies. T he D WI o pe ra te s a s ta tu to r y s ch em e t ha t a ss es se s a nd a pp ro ve s ( if

a p pr o pr i a te ) t h e u s e o f c h em i ca l s i n t r ea t in g d r in k in g w a te r. T h is s c he m e a l soc ov er s t he c on st ru ct i on m at er ia ls u se d t o b ui ld w at er t re at me n t p la nt s a nd

d is tr ib ut io n s ys te ms . T hi s s ch em e i s t o p ro te ct t he p ub li c b y e n su ri ng t ha t a ll

c he mi c al s a dd ed t o w at er a re s af e, a nd t ha t t he c he mi ca ls w hi ch l ea ch f ro m

c o ns t ru c ti o n m a te r ia l s a r e a l so s a fe . I t i s a l so i m po r ta n t t h at s u ch c h em i ca l s d o

n o t e n co u ra g e m i cr o bi a l g r ow t h i n d i st r ib u ti o n s ys t em s t h at w ou l d a f fe c t t h e

t a s t e o r o d o u r o f t h e w a t e r . ( 9 ) To p r ov i d e a u t ho r i t a t iv e g u i da n c e o n a n a l yt i c a l

m e th o ds u s ed i n t h e m o n i to r i ng o f d r in k i ng w a te r .

A l l t h e w a te r s u pp l y c o mp a ni e s a r e i n sp e ct e d a n nu a ll y, a l th o ug h t h e l e ve l o f

i n sp e ct i on w i ll v a ry f r om y e ar t o y e ar. I n t h e r e p o rt t h at f o ll o ws t h e i n sp e ct i on ,

a r ea s o f c o mp l ia n ce a n d n o n- c om p li a nc e a r e i d en t ie d a n d r e co m me n da t i on s

m ad e t o e ns ur e f ul l c om pl ia nc e w it h s ta t ut or y r eq ui r em en ts , w hi ch i nc lu de s

prosecution where necessary. The DWI checks the sampling procedures and the

l oc at io n o f s am pl in g p oi nt s t o e ns ur e t ha t t he y a re r ep re se nt at iv e o f w at er

q u al i t y w i th i n e a ch w a te r s u pp l y z o ne . A b ou t 9 0 d i ff e re n t l a bo r at o ri e s a n al y ze

w a te r s u pp l i es f o r t h e w a te r c o mp a ni e s. D u ri n g i n sp e ct i on t h e p r oc e du r es u s ed

a nd t he t ra i ni ng a nd c om pe t en ce o f l ab or at or y s ta ff a re e xa mi ne d . T he a ct ua l

r e s u l t s f r o m s a m p l i n g a r e a l s o s c r u t i n i z e d , a s i s t h e d a t a - h a n d l i n g s y s t e m u s e d t o

analyz e them, which is done to ensure that the integri ty of the data is

m a i n t a i n e d . T h e D W I c o n c e n t r a t e s o n t h o s e r e s u l t s t h a t h a v e n o t c o m p l i e d w i t h



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t h e N a ti o na l S t an d ar d s, a n d e n su r es t h at t h e c o rr e ct f o ll o w- u p a c ti o n h a s b e en

t ak en . E ve ry d ay p ro ce du re s a r e c he ck ed a nd a ll t he d at a r ec or de d o n p ub li c

registers.

T h e D W I o n ly c o ve r s E n gl a nd a n d Wa l e s s o n e it h e r S c ot l a nd n o r N or t he r n

I re la nd h av e a s pe cic a g en c y c o nc e rn e d w i th d r in k in g w a te r q u al i ty, w h ic h

r e ma i ns t h e r e sp o ns i bi l i ty o f g o ve r nm e nt i n t h e f o rm o f t h e S c ot t i sh E x ec u ti v e

a n d t h e N o r th e r n I r e l an d Wa t e r S e r v ic e r e s pe c t i v el y.

E n vi r on m en t al q u al i t y r e g u la t io n i n E n gl a nd a n d Wa l es i s c a rr i e d o u t b y t h e

E n vi r on m en t A g en c y (www.environment-agency.gov.uk ) , w hi ch r ep la ce d t he

National Rivers Authority in April 1996. The local authorities have retained

t h ei r p u bl i c h e al t h r e sp o ns i bi l i ti e s a s t o t h e w h ol e so m en e ss o f d r in k in g w a te r,

a n d h a ve s p ec i a l p o we r s t o d e al w i th p r iv a te s up p li e s. T h e r e gu l at i on s r e fe r ri n g

t o w at er a bs tr ac ti o ns , i mp ou nd me nt s a nd d is ch ar ge s o f w as te wa te rs i s t he

r e sp o ns i bi l it y o f t h e E n vi r on m en t A ge n c y. T h ei r m a in r e gu l a to r y f u nc t io n sc o ve r ( 1 ) w a te r r e so u rc e s ( m os t ly a b st r a ct i on s , f o r w h ic h t h ey i s su e l i ce n ce s a s

w e ll a s i n de p en d en t ly m o ni t or i ng r i ve r q u al i t y) ; ( 2 ) p o ll u ti o n c o nt r ol t h ro u gh

t h e i s s u i n g o f d i s c h a r g e l i c e n c e s , a l s o k n o w n a s c o n s e n t s , t o b o t h i n d u s t r i e s a n d

s e wa g e t r ea t me n t w o rk s o p er a te d b y t h e w a te r s e rv i ce c o mp a ni e s; ( 3 )sheries;

( 4) l an d d ra in ag e a nd o o d p r ot e ct i on ; a n d n a ll y ( 5 ) c o ns e rv a ti o n, a m en i ty,

r e cr e at i on a n d n a vi g at i on . W h il e D e fr a a l so h a s r e gu l at o ry f u nc t i on s, i t i s t h e

a c t i v i t i e s o f t h e D W I t h a t a r e o f m o s t i m p o r t a n c e w i t h r e s p e c t t o d r i n k i n g w a t e r .

T he S co tt i sh E nv ir on me nt P ro te ct io n A ge nc y ( SE PA ) (www.sepa.org.uk )

c ar ri es o ut a s im il ar f un ct io n t o t he E nv ir on me nt A ge nc y a nd h as t he d ut y t o

c on tr ol d is ch ar ge s t o r iv er s a nd s ea s, c on se rv e w at er r es ou rc es , p re ve nt pollution and promote conservation throughout Scotland. In Northern Ireland,

t h e W a t e r S e r v i c e i s m o n i t o r e d b y t h e E n v i r o n m e n t a n d H e r i t a g e S e r v i c e (www.

ehsni.gov.uk ).

1 .4 .2 C ha rg es

O n e o f O f w a t s m o s t i m p o r t a n t t a s k s i s r e v i e w i n g i n c r e a s e s i n c h a r g e s m a d e b y

t h e w a te r c o mp a ni e s. U nd e r a c o mp l ex p r ic i ng f o rm u la t h e w at e r c o mp a ni e s i n

E ng la nd a nd Wa le s c an i mp os e p ri ce i nc re as es i n l in e w it h t he c ur re n t r at e o f

ina t i o n p l u s a n i n d i v i d u a l s u m k n o w n a s t h e K f a c t o r . T h i s e x t r a c h a r g e K takes

a cc ou nt o f t he n ee d t o n an ce t he m aj or i mp ro ve me nt s p ro gr a mm e a nd t he

a mo un t i s d ec id ed b y O fw at e ac h y ea r. T he p ro du ce r p ri ce s c on st ru ct io n

o ut pu t i nde x i s u se d whe n c ons ide ri ng c os t pa ss t hr ou gh. Fo r c ap it al

e xp en di tu re p ri ci n g, a n i nd ex s pe cic al ly a pp li ed t o t he w at e r i nd us tr y, t he

public works non-roads index (PWNRI) is used. The representative weighting in

t h e r e t a i l p r i c e i n d e x ( R P I ) f o r g a s , t e l e c o m s a n d w a t e r a r e 2 . 1 % , 1 . 6 % a n d 0 . 7 %

r es pe c ti ve ly. T he b as ic r eg ul a ti on o f c ha rg e i nc re as es ( %) i s b y t he f or mu la

RPI K, s o m os t c ha rg es r is e e ac h y ea r b y K p e rc e nt a g e p o in t s m o re t h an t h e

a nn ua l r is e o f i n

a ti on . T ho se c ha rg es c ov er ed b y t hi s f or mu la a re t he b as ke t

http://www.environment-agency.gov.uk/http://www.sepa.org.uk/http://www.ehsni.gov.uk/http://www.ehsni.gov.uk/http://www.ehsni.gov.uk/http://www.ehsni.gov.uk/http://www.sepa.org.uk/http://www.environment-agency.gov.uk/


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i t em s , w h ic h a r e u n me a su r ed w a te r s up p ly a n d s e we r ag e s e rv i ce s , m e as u re d

( me te re d) w at er s up pl y a nd s ew er ag e s er vi ce s, a nd a ls o t ra de e f u e nt , w h ic h

c o v e r s m o s t w a t e r c o m p a n y c h a r g e s . T h e v a l u e o f K w a s s e t f o r t h e r s t t i m e i n

J an ua ry 1 99 1 w he n O fw at c al cu la te d t he R PI a s 9 .7 %, c om pa re d t o 2 .4 3% i n2 0 05 , a n d a l lo w ed v a ry i ng K v a lu e s f o r e a ch w a te r u n de r t ak e r. I n r e ce n t y e ar s

t h e f o r m u l a K RPI U h a s b e e n u s e d w h e r e U i s a n y u n u s e d K t h e c o m p an yw is he s t o c ar ry f or wa rd f or u se i n f ut ur e y ea rs ( Ta bl e 1.7) ( Of wa t , 2006).

P ri ci ng i s n ow d on e u si ng a n an c ia l m od el c al le d A qu ar iu s 3 w hi ch c an b e

e x am i ne d o n O f wa t 's w e bs i te .

C ha rg in g h ou se ho ld c us to me rs f or w at e r a nd s ew er ag e i s b as ed o n t hr ee

d i ff e re n t s y st e m s: ( 1 ) u n me t er e d c h ar g es t h at a r e e i th e r x ed o r b as ed o n t he

r at ea bl e v al ue ( RV ) o f t he c us to me r s p ro pe rt y; ( 2) m et er ed c ha rg es t ha t a re

based on the amount of water recorded by the customers m e t e r ; o r ( 3 ) a s s e s s e d

c h a r g e s t h a t a r e b a s e d o n t h e a m o u n t o f w a t e r a c u s t o m e r w o u l d b e l i k e l y t o u s e

i f h e / s h e h a d a m e t e r . I n E n g l a n d a n d W a l e s u n m e t e r e d c o n s u m e r s h a v e t h e r i g h t

t o r eq ue st a w at er m et er, w hi ch i s t te d f re e o f c ha rg e. O n t he o th er h an d

c o m p a n i e s h a v e t h e r i g h t t o c o m p u l s o r i l y i n s t a l l m e t e r s w h e r e t h e r e i s a c h a n g e

o f o c c u p i e r o r w h e r e a c u s t o m e r ( 1 ) w a t e r s h i s / h e r g a r d e n u s i n g a n o n - h a n d - h e l d

a pp li an ce ; ( 2) h as a s wi mm in g p oo l o r p on d w it h a c ap ac it y >1 0 0 00 l it re s

t h at i s r e pl e ni s he d a u to m at i ca l ly ; ( 3 ) h a s a b a th , s p a o r J a cu z zi w i th a c a pa c it y

>2 3 0 l i t r e s ; ( 4 ) h a s c e r t a i n t y p e s o f s h o w e r , i n c l u d i n g p o w e r s h o w e r s ; ( 5 ) h a s a

w a t e r t r e a t m e n t u n i t t h a t i n c o r p o r a t e s r e v e r s e o s m o s i s ; o r ( 6 ) l i v e s i n a n a r e a o f

w a te r s c ar c it y a s d e te r mi n ed b y t h e S e cr e ta r y o f S t at e .

Ta b l e 1 .7 P r ic e l i mi t s, i n cl u di n g K , u s ed i n t h e c a l c ul a ti o n o f w a te r c h ar ge s b y w a te r s e r vi c e c o mp a ni e s i n

England and Wales during 2006/7. (Adapted from Ofwat (2006) with permission from Ofwat.) The retail

price index (RPI) for this period is 2.43. Unused K is carried forward (U)

W a t er C o m pa n y K f o r 2 0 06 / 7 ( % )

P r i c e l i m i t

(K RP IU)

(%)

Actual

i n c re a s e i n

average

c h a rg e ( % )

U carried

f o r w ar d ( % )

U f r o m 2 0 05 / 6

(%)

Anglian 0.0 2.43 2.43

Dwr Cymru 3.6 11.09 6.41 4.68 5.06

Northumbrian 3.7 6.16 6.16 0.03

Severn T rent 4.8 7.23 6.58

South West 9.8 12.23 12.23

Southern 3.9 6.33 6.33

T hames 2.1 4.53 4.53

United Utilities 6.4 8.83 8.82 0.01

Wessex 4.9 7.33 7.33

Yorkshire 4.9 7.33 7.33

Weig hted average 4.0



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M et e re d c ha rg es c om pr is e o f t wo e le me nt s, a x ed s ta nd i ng c ha rg e a nd av ol um e tr ic c ha rg e b as ed o n t he a mo un t o f w at er u se d ( Ta bl e 1.8) . O nl y t wo

c o mp a ni e s h a ve i n tr o du c e d m e te r ed t a ri f fs t o r e wa r d l o w- v ol u me u s er s . T h es e

a r e A n g l i a n W a t e r ( w h i c h n o w o w n s H a r t l e p o o l W a t e r C o m p a n y ) a n d M i d K e n t

Wa te r C om pa ny. T he t ar if f i nc lu de s n o s ta nd in g c ha rg e b ut c on su me rs p ay a

h ig he r v ol um et ri c c ha rg e. S o i n o rd er t o b re ak e ve n t he y m us t u se


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t o 1 4 9 f o r u n m e t e r e d s u p p l i e s . T h e a v e r a g e u n m e t e r e d w a t e r s u p p l y b i l l v a r i e d

f o r t h is p e ri o d f r om 11 2 ( S ou t he r n Wa t er ) t o 1 69 ( S ou t h We s t Wa t er ) f o r t h e

s er vi ce c om pa ni es a nd f ro m 80 ( Po rt sm ou th Wa te r) t o 16 7 ( Te nd ri ng

H un dr ed Wa te r) f or t he w at er o nl y c om pa ni es . S o a l it re o f t ap w at e r c os ts o n

a v er a ge a b ou t 0 .1 0 o r 0 .1 9 i n cl u di n g t h e f u ll c o st o f s e wa g e t r ea t me n t .

To g et h er t h e U K w a te r c o mp a ni e s s u pp l y d r in k in g w a te r t o o v er 2 0 m i ll i on

properties and operate 1000 reservoirs and over 2500 water treatment works.

Tog et he r wi th 90 00 se wa ge t re at me nt wo rk s a nd i n e xc ess o f 7 00 00 0

k il om et re s o f m ai ns a nd s ew er s t he y h av e a n a nn ua l t ur no ve r o f m or e t ha n

7 b il li on m ak in g w at er a v er y b ig b us in es s i nd ee d. E ac h y ea r m or e t ha n

3 b il li on a re i nv es te d b ac k i nt o t he i nd us tr y i n E ng la nd a nd Wa le s a lo ne .

1.5 Water conservation

1 .5 .1 W at er d e ma nd m a na ge me nt

W a t e r d e m a n d m a n a g e m e n t ( W D M ) , a r o s e f r o m t h e k e y p r i n c i p l e s o f t h e D u b l i n

Statement (ICWE, 1992) , w h i c h w e r e r e s t a t e d a t t h e S e c o n d W o r l d W a t e r F o r u m

h e l d a t T h e H a g u e i n 2 0 0 0 . W a t e r d e m a n d m a n a g e m e n t , s o m e t i m e s r e f e r r e d t o a s

d e ma nd -s id e m an ag em en t, u se s a r an ge o f t oo ls s uc h a s c on se rv at i on , p ri c in g,

water-efc i en t t ec hn ol og i es a nd p ub li c e du ca ti on i n c on ju nc t io n w it h e xi st in g

water supply infrastructure (i.e. supply-side management) to address the problems

o f d w in d li n g w a te r s u pp l ie s a n d e s c al a t in g w a te r d e m an d . T h e s h or t fa l l b e t we e n

s up pl y a nd d em an d i s a w or l dw id e p ro bl em t h at i s b ei ng e xa ce rb at e d i n m a ny

a r e a s b y c l i m a t e c h a n g e . A l t h o u g h a p p l i c a b l e t o a l l w a t e r u s e r s i n c l u d i n g i n d u s t r ya n d t h e b i g g e s t u s e r a g r i c u l t u r e , t h e s e c t i o n b e l o w d e a l s o n l y w i t h d r i n k i n g w a t e r

s u pp l ie s . Wa t e r d e m an d m a na g em e n t h a s b e e n p i o n e er e d i n C a na d a t h r ou g h t h e

POLIS water sustainability project (POLIS, 2005) a n d i n A u s t r a l i a , w h e r e t h e rst

w at er u se e f c i e nc y l a b el l in g s c he m e h a s r e c en t l y b e en i n t ro d uc e d ( A us t ra l i an

Government, 2005) . Spe cic actions may incl ude the integrate d use of

c o n s er v a t i on m e a s ur e s , m e t e r in g , c h a r gi n g , b u i l d in g r e g u l at i o n s i n c o r po r a t i ng

w at er u se m in im i za ti on , a nd t he i nc re as ed w at e r u se e f c i en c y o f a p pl i an c es

and x tu re s. To b e s uc ce ss fu l, W DM a ls o r eq ui r es t he d ev el op me nt o f n ew

m a na g e me n t t e ch n iq u es a n d s t ru c tu r es , t h e u s e o f d e ce n tr a li z ed t e ch n ol o gi e s,

a n d a c h an g e i n u s er a t ti t ud e s a n d b e ha v io u r.

Wa te r d em an d m an ag e me nt h as i de nt ie d the need to move away from

e x p e ns i v e , u n r e st r a i n ed a n d e c o l o gi c a l l y d a m a gi n g i n f r a st r u c t ur a l d e v e lo p m e nt

a ss oc i at ed w it h c on ti n ua ll y i nc re a si ng w at er p ro du ct i on . R at he r i t a im s t o

r e p l a c e t r a d i t i o n a l e n g i n e e r e d s o l u t i o n s w i t h a m o r e s u s t a i n a b l e a p p r o a c h w h e r e

e xi st in g r es ou rc es a re u se d m or e e ff ec ti ve ly s o t he re i s n o l on ge r a n ee d t o

e xp lo i t n ew s ur fa c e o r g ro un d w at er r es ou rc es , o r d am ag e e xi st in g r es ou rc es

f ur th er b y i nc re as in g a bs tr ac ti on o r b y t he c on st ru ct io n o f i mp ou nd in g

r es er vo ir s. T he P OL IS p ro je ct h as p ro po se d t en k ey a ct io ns t o a ch ie ve a

m o re s u st a i na b le u s e o f w a te r r e so u rc e s ( Ta b le 1.9) ( B r a n d e s , 2006) . A l l h a d t o



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Ta b l e 1 .9 T he t en k ey s t ep s i de nt ie d b y t h e P O LI S p ro j ec t t o a c hi e v e w a te r s u st a i na b il i t y. A d ap t ed f ro m

Brandes (2006) with permission from POLIS project, University of Victoria

Priority area Actio ns

Leakage co ntro l Locate and repair leaks:

Distrib u tio n n etwo rk

S u pp l y p i p es

Ho u seh o ld leaks

Water-effi cien t ap p lian ces

a n d fi x t ur e s

R e pl a c e t h e f o l lo w i ng w i t h

water-effi cien t mo d els:

Toilet

Showerhead

Taps/faucets

Wash in g -mach in e (lau n d ry)

Dish wash er

I m p le m e nt a t io n o f w a t er

d e m an d m a n ag e m en t ( W D M )

C r e at i o n o f p e r ma n e nt W D M s t a ff

I n t eg r a ti o n w i t h e x i st i n g s u p pl y - s id e m a n ag e m en t

S u f fic i e nt fi n a nc i a l s u p po r t

L o ng - t er m c o m m it m e nt t o W D M

L i nk i ng w a te r c on s er v at i on a n d de v el o pm e nt M a ke w a te r i nf r as t ru c tu r al f u nd i ng d e pe n de nt

o n W DM

C ap p in g l o ca l w a te r u s e s o t h at f u rt h er

d e ve l o pm e n t i s d e pe n d en t o n o f f se t t i ng n e w

d e m an d t h r ou g h c o n s er v a ti o n

Co nservation-orientated pricing Universal metering

Vo lu me-b ased p ricin g

Plann ing sustain ably Long-term strategic plann ing

S o f t- p a th a p p ro a c h t o p l a nn i n g

Rainwater harvestin g P romote decentralized infrastruc tu re

N ew b ui l di n gs t o r e ly o n r a in w at e r a s p r im a ry

w a t er s o u rc e

D e v el o p n e w g a r de n i ng m e t h od s

Water reuse P romote decentralized infrastru ctu re

D e v el o p h i g h- p r ofi l e d e m on s t r at i o n p r o je c t s t ob u i ld c o m m un i t y s u p po r t

Water-sen sitive urban d esign Integrate land use d ecis ion s and planning with

c a t c hm e n t m a n ag e m en t a n d w a t er c o n s er v a ti o n

Edu catio n Develo pment of a water ethic

I d e nt i f y a n d t a r ge t h i g h- w a t er - u s e g r o up s

P ro mo te co mmu n ity in vo lvemen t

P r o mo t e p r a ct i c a l a d v ic e a n d s o l ut i o ns

1.5 Water cons ervatio n 19


38/537

m e et t h e b a si c c r it e ri a o f b e in g t e ch n ic a ll y f e as i bl e , b r oa d ly a p pl i ca b le , s o ci a l ly

a c ce p t ab l e a n d c o st e f fe c ti v e c o mp a re d t o n o rm a l i n fr a st r uc t ur a l d e ve l op m en t .

T h es e a r e c o ns i de r ed b e lo w i n d e ta i l.

1 .5 .2 L ea k r e du ct io n i n w at er m ai ns

A l l w a t e r d i s t r i b u t i o n s y s t e m s s u f f e r f r o m l e a k s , w i t h t h e d e g r e e o f l o s s r e l a t e d t o

t h e a g e o f t h e p i p e w o r k . S o a s o u r s y s t e m s a g e m o r e w a t e r i s l o s t r e q u i r i n g e v e r

i nc re as in g i nv es tm en t t o m en d l ea ks . I n C an ad a 1 3% o f t he t ot al v ol um e o f t re at ed

w at er i s l o st v ia l ea ks , w h i le i n t h e U K i t i s 2 4 % e q u iv al en t t o 3 6 08 M l d1. I t i s

r e l a t i v e l y e a s y t o s a v e b e t w e e n 5 % a n d 1 0 % b y h a v i n g a d e d i c a t e d l e a k d e t e c t i o n

a n d r e p a i r s e r v i c e . H o w e v e r , i n t h e U K , t h e n a t i o n a l l e a k a g e r a t e h a s r e m a i n e d a t

a p p r o x i m a t e l y t h e s a m e l e v e l f o r a d e c a d e e v e n t h o u g h i n c r e a s i n g e f f o r t i s s p e n t

i n l e a k d e t e c t i o n a n d r e p a i r e a c h y e a r ( F i g u r e 1.1).There are a numbe r of ways in which leaks can be detect ed in water

n e t w or k s : w a t e r a u d i ts , s o n ic l e a k d e t e c t i o n a n d p a s si v e d e t e c ti o n . W a t er a u d i ts

c o m p a r e t h e a m o u n t s u p p l i e d t o t h e a m o u n t c o n s u m e d u s i n g w a t e r m e t e r s a t t h e

s up pl y a nd h ou se ho ld er s e nd s o f t he d is tr ib ut io n n et wo rk ( i. e. i nt eg ra te d

m e t e r in g ) . T h e I n t e rn a t i on a l Wa t e r A s s oc i a t i o n ( I WA ) a n d t h e A m e r i ca n Wa t e r

Wo r k s A s s oc i a t i on ( AW WA ) h a v e j o i n tl y d e v e lo p e d a s o p hi s t i c at e d w a t e r a u d i t

s y st e m t h at t a ke s i n to a c co u nt s y st e m- s pe c ic f ea tu re s s uc h a s p re ss ur e a nd

l en gt h o f p ip ew or k. T hi s m od el a ll ow s w ho le s ec ti on s o f t he w at er s up pl y

n e t w o r k t o b e c h e c k e d a t t h e s a m e t i m e a l l o w i n g a w a t e r b a l a n c e t o b e d r a w n u p

s o t ha t a ll w at er c an b e a cc ou

drinking water quality problems and solutions

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