Urban Water

Urban Water

Department of Hydro Sciences, Institute for Urban Water Management

Peter Krebs Dresden, 2010

1 Global water aspects

2 Introduction to urban water management

3 Basics for systems description

4 Water transport

5 Matter transport

6 Introduction to water supply

7 Water extraction

8 Water purification

9 Water distribution

10 Introduction to wastewater disposal

11 Urban drainage

12 Wastewater treatment

13 Sludge treatment

Urban Water Chapter 5 Introduction to water supply © PK, 2010 – page 2


5.1 Goals of water supply

5.2 Overview over water supply system

5.3 Water need


Peter Krebs

Urban Water





5.3 Water need


Peter Krebs

Urban Water


„Sufficient Drinking Water of good Quality at any Time “

Political decision making

sufficient how much, how long during dry periods ?

good quality hygiene, to be drunk, for toilet flushing, how long ?

any time extreme drought, contaminated water spring

Task of water supply


Implementation via guidelines, threshold values

DIN 2000

„Drinking water should be appetizing and tempting,

colourless, clear, cold, odourless, and perfectly fresh with

regard to taste.“

Drinking water quality


Att./No.

Parameter Unit Limit value

1/1 Escherichia coli (100 ml)-1 0

1/2 Enterokokken (100 ml)-1 0

1/3 Coliforme Bacteria (100 ml)-1 0

2/I/1 Acrylamid mg/l 0,0001

2/I/2 Benzole mg/l 0,001

2/I/3 Boron mg/l 1

2/I/4 Bromate mg/l 0,01 *) (01.01.2008)

2/I/5 Chrome mg/l 0,05

2/I/6 Cyanide mg/l 0,05

2/I/7 1,2-Dichlorethane mg/l 0,003

2/I/8 Fluoride mg/l 1,5

2/I/9 Nitrate mg/l 50

2/I/10 Biozids individual mg/l 0,0001

2/I/11 Biozids in total mg/l 0,0005

Limits (i), EU


Att./No.


2/I/12 Mercury mg/l 0,001

2/I/13 Selen mg/l 0,01

2/I/14 Tetra-chlore-ethen und Tri-chlore-ethen mg/l 0,01

2/II/1 Antimon mg/l 0,005

2/II/2 Arsenic mg/l 0,01

2/II/3 Benzo-(a)-pyren mg/l 0,00001

2/II/4 Lead mg/l 0,01 *) (01.12.2013)

2/II/5 Cadmium mg/l 0,005

2/II/6 Epichlorehydrine mg/l 0,0001

2/II/7 Copper mg/l 2

2/II/8 Nickel mg/l 0,02

2/II/9 Nitrite mg/l 0,5

2/II/10 Polycyclic aromatic carbon hydroxids mg/l 0,0001

2/II/11 Trihalogenmethane mg/l 0,05

2/II/12 Vinyl chloride mg/l 0,0005

Limits (ii), EU


Anl./Nr. Parameter Unit Limit value

3/1 Aluminium mg/l 0,2

3/2 Unionised Ammonia mg/l 0,5

3/3 Chloride mg/l 250

3/4 Clostridium perfringens (100 ml)-1 0

3/5 Ferric mg/l 0,2

3/6 Colour (spectral Absorption coefficientHg 436 nm)

m-1 0,5

3/7 Odour limit value 1 2 at 12 °C, 3 at 25 °C

3/8 Taste 1 Acceptable for consumer

3/9 Colony number at 22 °C 1 Without anomal change

3/10 Colony number at 36 °C 1 Without anomal change

3/11 Conductivity S/cm 2500 at 20 °C

3/12 Manganese mg/l 0,05

3/13 Sodium mg/l 200

Limits (iii), EU


Att./No.


3/14 Total organic carbon (TOC) Without anomal change

3/15 COD mg/l O2 5

3/16 Sulfate mg/l 240

3/17 Turbidity (NTU) 1,0

3/18a Hydrogen pH 6,5 und 9,5

3/18b Calcit solution capacity mg/l CaCO3 At purification station: 5combined water: 10

3/19 Tritium Bq/l 100

Limits (iv), EU





5.3 Water need


Peter Krebs

Urban Water


Ground water

Storage

Industry

Settlement

Lake, dam

Water protection

Tight construction

Protection zone

Pressure

Saftey barriers

Spring intake

Protection zone

Purification

Water distribution

Structure of a water supply system


Regional water supply systems in Germany


Regional water supply system in USA


0

1.000

2.000

3.000

4.000

5.000

6.000

7.000

1991 1995 1998

Consu

mpti

on p

er

year

in 1

06 m

³

Ground- and spring water River bank filtrate Surface water

0

200

400

600

800

1.000

1.200

1.400

Saxony Bavaria NRW

(Umweltbundesamt (2001), pp. 52ff.)

Consumption and origin of drinking water in Germany





5.3 Water need


Peter Krebs

Urban Water


Variations in consumption

Climate variations (Dry / wet years)

Variations in Economy

Changes in consumption

Trends in population development

Technical development

Comfort and Hygiene

Consumption pattern

Living standard

Law, guidelines

…

Effects on water need


Qd average daily consumption over a year

Qh average hours consumption at average day

Qd,max maximum daily consumption of a year

Qh,max maximum hours consumption at maximums day

fd Peak days factor

fh Peak hours factor

Parameters to characterise consumption (i)


Parameter Decisive for

Maximum daily water needQd,max = fd ∙ Qd

Purification, reservoir

Average hourly need at average day Qh = Qd / 24

Maximum hours need at maximum day Qh,max = fh ∙ Qd / 24

Distribution system

Parameters to characterise consumption (ii)


28%

34%

12%

6%6%

6% 4% 2%2%

28% WC

34% bathing/shower

12% washing cloths

6% personal hygiene

6% wash dishes

6% cleaning

4% watering

2% cooking/drinking

2% cleaning cars

Drinking water consumption of private households

Documents

Urban Water