WATER TREATMENT TECHNOLOGY (TAS 3010) LECTURE NOTES 10 - Water Distribution System

Izan Jaafar, Engineering Science, FST, UMTIzan Jaafar, Engineering Science, FST, UMT

© SHAHRUL ISMAIL, DESc.University College of Science and Technology Malaysia

CHAPTER 3:Environmental Microbiology

CHAPTER 10 : CHAPTER 10 : CHAPTER 10 : CHAPTER 10 :

TAS 3101 : WATER TREATMENT TECHNOLOGY

Water Water

Distribution Distribution

System System

Water Water

Distribution Distribution

System System

Izan Jaafar, Engineering Science, FST, UMTIzan Jaafar, Engineering Science, FST, UMT

Menu

1) Introduction

2) Water Distribution

3) Distribution Types

4) Distribution Requirement

5) Storage Reservoir

6) Distribution Pipes

7) Wastage

Izan Jaafar, Engineering Science, FST, UMTIzan Jaafar, Engineering Science, FST, UMT

- “Delivery of water from pumping station by gravity flow and delivers it thorughout the district to be served.

- Includes reservoirs for purposes of storage, equalizing pressures and subsequent distribution, together with pipes, valves, hydrant and other appurtenances for carrying waters, service pipes, meters etc.

- Enable the water utility to deliver water to its customer with maintaining the biological quality of water in the distribution system. Assessment : Collecting routine water quality samples from the distribution system and analyzing them for the presence or absence of total coliform bacteria.

Introduction

Izan Jaafar, Engineering Science, FST, UMTIzan Jaafar, Engineering Science, FST, UMT

- “To stop, start or control the flow of water’

- Different valves are used to perform different functions

- Some valves, e.g. butterfly, globe, pinch and needle valves are also used for throttling the flow

- Other types; e.g. check valves used to control the direction of the flow of water

Distribution System Valves

Izan Jaafar, Engineering Science, FST, UMTIzan Jaafar, Engineering Science, FST, UMT

- Damage :

i. Corrosion or rusting internally – Water quality

ii. Corrosion or rusting externally – Nature of soil conditions.

- Materials : Adequate strength and durability

- Sufficient pressures must be maintained

- Must be installed at sufficient depths below the ground surface – protection against traffic loads.

Water Distribution

Izan Jaafar, Engineering Science, FST, UMTIzan Jaafar, Engineering Science, FST, UMT

- Quality of distribution system influence internal corrosion rate of distribution system pipes.

- Main quality parameters affect corrosion rates:

1. pH 5) Chlorides

2. Hardness 6) Sulphates

3. Dissolved Oxygen 7) Chlorine

4. Total Dissolved Solids 8) Hydrogen sulphide

9) Bacteria

Damage

Izan Jaafar, Engineering Science, FST, UMTIzan Jaafar, Engineering Science, FST, UMT

1) Sufficient capacity of water

2) Sufficient pressure

3) Low-cost

4) Easier to maintain

5) Stable condition

Distribution - Requirement

Izan Jaafar, Engineering Science, FST, UMTIzan Jaafar, Engineering Science, FST, UMT

TYPESTYPES

GRAVITY GRAVITY DIRECT PUMPEDDIRECT PUMPED

GRAVITY AND PUMPEDGRAVITY AND PUMPED

Distribution - Types

Izan Jaafar, Engineering Science, FST, UMTIzan Jaafar, Engineering Science, FST, UMT

1) Gravity force

2) The water level or water distribution plant located higher from the service areas

3) Not using pump

4) Low-cost and effective

1 – Gravity System

Izan Jaafar, Engineering Science, FST, UMTIzan Jaafar, Engineering Science, FST, UMT

GRAVITY FLOW

Supply Source (Dam)

Treatment Plant

Service Reservoir

Service Area

GRAVITY SYSTEM

1 – Gravity System – Con’d

Izan Jaafar, Engineering Science, FST, UMTIzan Jaafar, Engineering Science, FST, UMT

1) Pumped direct to the consumer

2) Level of water sources is at the same height or lower from the service areas

3) Power failure – breakdown the system

4) Several types of pump

5) Expensive

6) Less Effective

2 – Direct Pumped System

Izan Jaafar, Engineering Science, FST, UMTIzan Jaafar, Engineering Science, FST, UMT

River

Treatment Plant

Service Area

DIRECT PUMP SYSTEM

Pump

Pump

Direct Pumped System – Con’d

Izan Jaafar, Engineering Science, FST, UMTIzan Jaafar, Engineering Science, FST, UMT

1) Combination – Pump and Gravity

2) Excess water during low water demand will kept in the storage tank

3) Economical, pump used at constant rate

3 – Gravity & Pumped System

Izan Jaafar, Engineering Science, FST, UMTIzan Jaafar, Engineering Science, FST, UMT

River

Treatment PlantService Area

GRAVITY AND COMBINATION SYSTEM

Pump

Pump

Service Reservoir

Gravity Flow

Gravity & Pumped System

Izan Jaafar, Engineering Science, FST, UMTIzan Jaafar, Engineering Science, FST, UMT

- Supply water during emergencies

- Equalize supply and demand

- Maintain constant pressure in the distribution system

- Other functions :

1) Provide water during peak demand

2) Provide disinfectant contact time

3) Allow for blending

4) Allow for one-shift treatment operations

5) Allow for optimization of pumping costs

6) Provide water hammer protection

7) Provide water during blackouts and natural disasters

Storage Reservoir

Izan Jaafar, Engineering Science, FST, UMTIzan Jaafar, Engineering Science, FST, UMT

DEAD END / DEAD END / TREE SYSTEMTREE SYSTEM

GRID SYSTEMGRID SYSTEM

RING / RING / CIRCLE SYSTEMCIRCLE SYSTEM

LAYOUT OF LAYOUT OF PIPE SYSTEMPIPE SYSTEM

Pipe System

RADIAL SYSTEMRADIAL SYSTEM

Izan Jaafar, Engineering Science, FST, UMTIzan Jaafar, Engineering Science, FST, UMT

1) Sub main pipe connect to main pipe

2) Old town and cities – irregular developed & no definite patterns of roads and streets.

3) Cheap and easily designed

4) Not effective

5) Water pressure drop at the end of the distribution pipe

6) Water become stagnant at the end of the distribution pipe

A – Dead End/Tree System

Izan Jaafar, Engineering Science, FST, UMTIzan Jaafar, Engineering Science, FST, UMT

Kampung A

Kampung B

Main Pipe

DEAD END/TREE SYSTEM

Dead End/Tree System

Izan Jaafar, Engineering Science, FST, UMTIzan Jaafar, Engineering Science, FST, UMT

1) Main pipe and branches arranged in grid sequences.

2) Effective during maintenance work

3) Effective during fire or emergency

4) No stagnant water

5) Design method more complex

6) High cost

B – Grid System

Izan Jaafar, Engineering Science, FST, UMTIzan Jaafar, Engineering Science, FST, UMT

Main Pipe

GRID SYSTEM

Grid System

Izan Jaafar, Engineering Science, FST, UMTIzan Jaafar, Engineering Science, FST, UMT

1) Main pipe is positioned covering the outer of the service area

Main Pipe

RING/CIRCLE SYSTEM

C – Ring or Circle System

Izan Jaafar, Engineering Science, FST, UMTIzan Jaafar, Engineering Science, FST, UMT

1) Town or city divided into various circular or square zones and distribution reservoirs placed at the centre of each zone.

2) Suitable when town or city can be oriented with radial roads and streets.

3) Water from main reservoir is allowed to flow through main pipe and sub-main pipe and get collected at the distribution reservoir of each zone

4) Water is supplied to consumers through distributor pipe lines.

D– Radial System

Izan Jaafar, Engineering Science, FST, UMTIzan Jaafar, Engineering Science, FST, UMT

Radial System

Izan Jaafar, Engineering Science, FST, UMTIzan Jaafar, Engineering Science, FST, UMT

WASTAGEWASTAGE

LEAKING PIPELEAKING PIPE WATER METERWATER METER

STOLENSTOLEN

Distribution - Wastage

Izan Jaafar, Engineering Science, FST, UMTIzan Jaafar, Engineering Science, FST, UMT

- Main function : provide water for firefighting

- Spacing and location : Depends on fire protection and insurance needs

- Other function :

i. Flush the distribution system lines to remove sediments and biogrowth accumulation

ii. Supply water to construction projects

iii. Provide water to water trucks and street sweepers

Fire Hydrant

Izan Jaafar, Engineering Science, FST, UMTIzan Jaafar, Engineering Science, FST, UMT

THANKS FOR THANKS FOR

YOUR ATTENTION…..YOUR ATTENTION…..

THANKS FOR THANKS FOR

YOUR ATTENTION…..YOUR ATTENTION…..