Water Loss Management In Distribution PipeBasic Knowledge

1. Water Balance IWA concept

3. Reduce Non Revenue water Concept

2. Water Loss Indicator

Why water loss is Important ?

- Lack of water resource

- Save operating cost

- Save energy for pumping

- Increase Level of operation pressure

- Reliability in distribution pipe system

- Excellent service quality

Background Leak

Main Leak

Can’t recordunavoidable

Can detect

Water Balance IWA concept

System

Input

volume

SIV

1715.8

(100%)

AuthorisedConsumption

1289.1(75.13%)

RW1282.4

(74.74%)

Non

Revenue

Water

(NRW)

433.4 (25.26%)

Bill Authorised

UnbillAuthorised

ApparentLosses

62.1 (3.6%)

RealLosses(CARL)364.6

(21.2%)

Water

Losses

UFW

426.7

(24.87%)

Billed Metered Cons 1282.4 (74.74%)

Unbilled Unmetered Cons 6.7 (0.39%)

Unauthorized Cons 17.2 (1%)

Customer Meter Inaccuracies & Data Handling Error 44.9 (2.6%)

Leakage on Trunk Mains

Billed Unmetered Cons 0 (0%)

Unbilled Metered Cons 0(0%)

Leakage on Service Connectionsup to metering point

Show each component of water

Leakage on Distribution Mains

Billed Meter consumption = customer pay from billing system

Unbilled consumption = Amount water that can authorized from evaluate

Use in operation , Utility Blow off / Fire HydrantUse in construction/Repair

Authorized Consumption

Component of Authorized consumption

Customer useBlow off / Fire HydrantUse in construction

Apparent Loss / Commercial Loss

Physical loss / Real loss

Illegal in consumptionInaccuracy of Meter

Leakage in pipe

Water loss

Component of Water loss

UnbilledAuthoried

NRW

Advantage of using Water BalanceWB

- Show all components of water

- Clearly , Classify

- Low estimate Data / Realizable

Disadvantage of using Water BalanceWB

- Lack of Data / 1 Billing cycle for Water balance

- Customer billing cycle not finish in same time

- All of master meter must operation all time Error occur when estimate data

Water loss Indicator

UFW unaccounted of water

Volume / Percentage

NRW non revenue waterNRW non revenue water

Volume / Percentage

ILI Infrastructure leakage index

Non Unit

Water Audit Concept

Loss Indicator

“Top – Down”Water balance

Collect SIV , Componet each water

“Bottom - Up”Use MNF to evaluate

Amount of loss

MNF is the Minimum Flow rate at Night time

Assumption 1.Leakage all time 2. At night time Consumption is very low

3. MNF is nearless Leak flow 4. Use Daily MNF for estimate Water loss

Minimum Night Flow

%UFW

%UFW = %(SIV – Authorized consumption)/ SIV

Advance - Easy for Calculate - Easy for collecting data- Easy for monitoring Trend

In same area

Disadvantage - Error if over estimateAmount of water which Unmetered- Can not compare inSome area

Non revenue water

%NRW = %(SIV- Billed consumption) /SIV

Advantage - Easy - Refer to Revenue

Note - NRW > UFW

Example Calculate of UFW,NRW

SIV

5000

(100%)

AuthorizedRW?

Non

Revenue

Water

(NRW) ??

Billed

Unbilled

ApparentLosses

RealLosses(CARL)

Water

Losses

UFW ??

Billed Metered Cons 2500

Unbilled Unmetered Cons 300

Unauthorized Cons 100

Customer Meter Inaccuracies & Data Handling Error 150

Leakage on Trunk Mains 500

Billed Unmetered Cons 500

Unbilled Metered Cons 200

Leakage on Service Connectionsup to metering point 250

Leakage on Distribution Mains 500

3000 (60%)3000

500 3500 (70%)

1500 (30%)2000 (40%)

250

1250 24%

Area 1

Area 2

Area 3

Area 7

Area 4 Area 6

Area 5

15% 22%

32%

43%

7%

32%

38%

Water loss300 m3

270 m3

180 m3

600 m3

250 m3

350 m3

700 m3

Volume loss

450 กม.

800 กม.

250 กม.

180 กม.

700 กม.

400 กม. 300 กม.

Pipe length

%NRW

6

2

7

4

3

1

5

Volume

7

6

4

1

2

5

3

Length

7

5

1

4

6

3

2

High

Low

How to Ranking Area

Key factor independent to water loss

Water loss

Pipe length

Pressure

Seviceconnection

ILI infrastructure leakage index

ILI = CARL / UARL

Advantage - Use variable of factor - Use for Ranking Priority - Can compare for every area

Disadvantage - Many source of data - Hard to calculate

20

(Unavoidable Annual Real Losses, UARL)

Lm คอื Distribution pipe length (km)

Nc คอื No of Connection (point)

Lp คอื Service pipe length (Km)

P คอื Pressure ( m)

UARL= [18Lm + 0.8Nc + 25Lp]P (liter/day)

In each area that has differentComponent has unequal UARL

Standard operating Pressure = 50 m

(ILI)

CARL (Current annual real loss)

UARL(Unavoidable Annual Real Losses)

For example :

CARL from WB table 1,000,000 Liters/day

DMA has Pipe length = 30km , Service pipe = 3 km , 1500 concection , average P = 8 m

UARL = (18x30 + 0.8x1500 + 25x3)x8 = 14,520 Liter/sec

ILI: 1000000/14520 = 68.9

NRW

(%)

CARL

(Liters/Day)

UARL

(Liters/Day)

ILI

(times)

Area A 20 450 50 9

Area B 40 400 100 4

Area C 35 350 35 10

Example (ILI) VS NRW

1

147

.96

136

.83

91.1

3 123

.01

141

.48

352

.61

45.4

2

53.1

0

46.2

7

69.2

4

38.9

8

118

.13

164

.12

92.9

3

37.5

8

29.00 30.16

26.39

29.72 30.78

34.67

21.29

27.33

21.73

24.72

22.97

35.49

36.66

33.50

26.43

0

5

10

15

20

25

30

35

40

0

50

100

150

200

250

300

350

400

ILI VS UFW in Branch office of MWA

ILI

%Loss

ILI

UFW

CARL= 40%

ELL

Leakagemanagement

1)PressureManagement

2) Speed & Quality

of

Repairs

3) ALCALR - time

4) PipeReplacement4 Element of Sustainable Leakage Control Strategy as Contineous Improvement Activities

System Input Volume

PoorPressure Revenue

Water

High Pressure

Optimize Pressure

% Non-Revenue Water

UARL

Factor of loss volume

No of Leak point

Flow Rate

Uncontroling

-external force- Pipe Material

-Pipe age- Soil settlement

- Pressure- Leak area

- Metering Error - Illegal consumption

ELL Economic leakage level is the optimum

Level of leakage at the lowest Total Cost

Cost of water is vary direct to the amount of waterInvestment margin is vary indirect to %Reduce of NRWIn term of exponentioal

ELL

The Economic Balance

Cost of Leakage Control

LOSSES (ML/D)

Bac

kgro

un

d L

eak

age

and

Re

po

rte

d B

urs

t

CO

ST O

F LE

AK

AG

E C

ON

TRO

L A

ND

WA

TER

LO

SS

Economic Leakage LevelWhere the total cost is at a minimum

Economic Level of Leakage (ELL)

Leak Run Time Awareness

Time

Total volume loss= (A+L+R)time x Flow rate

AwarenessLocationRepair

AA LL RR

- Flow rate vary direct to Pressure - To reduce loss if can reduce ALR time

What is ALR time ?

Pressure Management

To control unnecessary flow rate

To increase consumption flow rate

To decrease error in meter recording

For efficient in Water loss activities

Relation between Loss & Pressure

n1(L/Lo) = (P/Po)N1

n1 Find from “Pressure step test”Generally = 0.5 – 1.5

FAVAD (Fixed and Variable Area Discharge)

L = Cd x A x (2gP)0.5

Pressure Management concept

Pressure Management concept

0

5

10

15

20

25

30

0

50

100

150

200

250

0 5 10 15 20 25

Flow independent to pressure (Consumption)

Pre

ssure

(m

)

Flow dependent to pressure (Leak)

Total Flow

Pressure Trend curve

Pressure Management

Active leakage control ??

Objective To Reduce Leak time A & L time

Monitoringsystem

Pin pointActivities

Loss & Ranking Warning & AleartSystem

Pipe replacement concept

Objective To Reduce Repair time

Protect for reburst pipe

Expand the life time of Pipe

- Limitation of Budget

- Plan for new investment project

- Limitation of Budget

- Financial analysis in project

- Evaluate & Priority of Pipe construction route

- Select the best of material & construction

technique by economic value

- Plan for new investment project

Q & AQ & A