river bank filtration experience in south jakarta indonesia

River Bank Filtration for

Cilandak Water Treatment Plant

Raw Water Optimization

Draft REPORT

2012

WATER RESOURCES DEVELOPMENT SECTION

WATER RESOURCES DEVELOPMENT & PROCESS OPTIMIZATION DEPARTMENT

WATER ENGINEERING SERVICES DIRECTORATE

WRD & PO WATER RESOURCE DEVELOPMENT

DEPARTMENT SECTION

Riverbank Filtration for Cilandak WTP Raw Water Optimization | i

LIST OF CONTENTS

LIST OF TABLES ii

LIST OF FIGURES ii

LIST OF ATTACHMENTS ii

1. BACKGROUND 1

2. OBJECTIVE 2

3. HYDROGEOLOGICAL STUDY 2

3.1 Exploration Wells and Pumping Test 2

3.2 Water Quality 3

4. RBF WELLFIELD DESIGN AND IMPACT ASSESSMENT 6

4.1 Design 6

4.2 Cilandak Shallow Aquifer Simulation 7

5. COST AND BENEFIT ANALYSIS OF THE PROJECT 7

5.1 Cost 7

5.2 Benefit 7

5.3 Cost and Benefit Analysis 9

6. WELLFIELD CONSTRUCTION 9

7. RBF FURTHER STAGES FOR THE FUTURE 11

ATTACHMENTS


DEPARTMENT SECTION

Riverbank Filtration for Cilandak WTP Raw Water Optimization | ii

LIST OF TABLES

Table 3.1 Water Quality of Surface Water and RBF Wells 4

LIST OF FIGURES

Figure 1.1 Riverbank Filtration Techniques 1

Figure 3.1 Pilot pumping tests at two RBF wells 2

Figure 3.2 Pumping Test of Cilandak wells 3

Figure 3.3 Electrical Logs Interpretation 3

Figure 3.4 Manganese, Ammonium and Turbidity of Cilandak raw water (2009 –

2010) 4

Figure 4.1 Wellfield and its Piping 6

Figure 4.2 Well / Borehole Design 6

Figure 5.1 Ammonium at Cilandak raw water 7

Figure 5.2 Manganese at Cilandak raw water 8

Figure 5.3 Detergent at Cilandak raw water 8

Figure 6.1 Drilling Activity 10

Figure 6.2 Coarse Sand Additions 10

Figure 6.3 New Well Constructed 11

LIST OF ATTACHMENTS

Attachment 1 Estimation Cost for Electrical Consumption of RBF Pumps 11

Attachment 2 Chemical Saving Calculation 12


DEPARTMENT SECTION

Riverbank Filtration for Cilandak WTP Raw Water Optimization | 1

1. BACKGROUND

Cilandak Water Treatment Plant is classical clarification / filtration treatment plant,

treating Krukut river waters since 1980, with a production capacity of 400 l/s. As there is an

increasing urban development in the upstream of Cilandak WTP, raw water becomes

progressively more polluted with domestic used water, thus rising Ammonia, Detergent and

Organic load, exceeding WTP’s ability to eliminate it completely, mainly during dry season. In

addition, Chemical OPEX has highly increased (mainly Activated Carbon and Chlorine

consumption) and raw water shortages are common when dry season reaches its peak.

Based on the above, riverbank filtration (RBF) technique could solve this deficit as RBF is a

cost-effective, natural treatment technology that takes advantage of geological and biological

natural filtration, instead of chemicals use, to treat surface water and groundwater supplies.

So, this technology is at the forefront as a method for not only treating existing raw surface

water supplies but also for developing new and sustainable water supplies. The use of

chemicals and production of sludge are minimized.

Moreover, RBF is a technique to capture water of the river by inducing it to flow through the

bank. So the advantages of RBF are:

� As bank storage

� Natural treatment process occurred

� Reduce dramatically turbidity

� Heavy metal sorption

� Adsorption and inactivation of microorganisms

� Biodegradation of organic pollutants

The illustration of RBF is available at Figure 1.1 below:

Figure 1.1 Riverbank Filtration techniques


DEPARTMENT SECTION


2. OBJECTIVE

River Bank Filtration in Cilandak Water Treatment Plant is a project aiming to improve

raw water quality in a first stage by capturing it by shallow wells near Krukut River through

natural biological and mechanical filtration. In a second stage, after upsizing transmission,

RBF water will be added at the outlet of the Plant in order to increase Cilandak WTP

production.

3. HYDROGEOLOGICAL STUDY

Hydrogeology Study is important for the project as it studies the water beneath the

earths’ surface, in particular groundwater. It also involves the flow and chemical interactions

of groundwater within aquifers and requires understanding of geology, math, physics and

chemistry. Groundwater dynamics, exploration, drilling and aquifers tests, sustainable

allocation of groundwater, contamination, and computer modeling are part of the study.

By the study, we will be able to explain in detail the impact of RBF wells to the surrounding

areas’ groundwater.

3.1 EXPLORATION WELLS AND PUMPING TEST

Feasibility study of RBF in Cilandak consisted in 2 exploration wells of 6 inches diameter and

30 meters depth. These boreholes were drilled at about 10 and 20 m respectively from

Krukut River.

The superficial geology of the region (Quaternary) is quite homogenous, composed by three

meters of red silt (soil) overlaying black volcanic sands until 30 m depth. Water table was

detected at 1 m below the soil surface level. Hydraulic conductivity of the sands is in the

order of 20 m/day, resulting from long term pumping tests, as seen in Figure 3.1 and 3.2.

Figure 3.1 Pilot pumping tests at two RBF wells


DEPARTMENT SECTION


Figure 3.2 Pumping Test of Cilandak Wells

Electrical logging is also a valuable water well drilling tool. It could locate and determine the

exact thickness and position of water bearing formations at specific site. For Cilandak wells,

the electrical logs interpretation is illustrated in Figure 3.1.


DEPARTMENT SECTION


Figure 3.3 Electrical Logs Interpretation

3.2 WATER QUALITY

The quality of Krukut River as Cilandak raw water is much fluctuated. Below is the graph

of Cilandak raw water quality 2009 – 2010.


DEPARTMENT SECTION


Figure 3.4 Manganese, Ammonium and Turbidity of Cilandak raw water

(2009 – 2011)

We estimate that Cilandak WTP has a limited capacity to eliminate Ammonium, a frequent

indicator of organic pollution, no more than 0,5 mg/l in raw water. As Krukut River waters

very often exceeds this concentration of Ammonium, it can be found in the treated water in

very fluctuant contents, normally below PERMENKES regulation maximal limits (1 mg/l) .

However, being Ammoniun a high consumer of Chlorine, it is very difficult to maintain a well

stable concentration of Free Chlorine in the treated water.

Another concern of raw water quality impacting on treated water is the high concentration of

Detergent.

While compared to the water coming from the RBF wells, the surface water was highly

polluted. Table 3.1 below shows the values by each parameter analyzed.

Table 3.1 Water Quality of Surface Water and RBF Wells

Surface Water RBF Water

Drinking

Water Standar

pH - 7.0 6.9 6.5-8.5

Turbidity NTU 79 2 5

Conductivity μmhos/cm 180 209

Nitrite mg/L 0.2 <0.01 3

Sulfate mg/L 13 6 250

Color PtCo

<4 15

Ammonium mg/L 0.8 <0.1 1.5

Iron mg/L 15.4 0.6 0.3

Manganese mg/L 1.6 0.2 0.4

Detergent mg/L 0.4 0.1 0.05

0

100

200

300

400

500

0

2

4

6

8

10

Jan-09 Jul-09 Jan-10 Jul-10 Jan-11 Jul-11 Jan-12

NT

U

mg

/L

Manganese Ammonium Turbidity


DEPARTMENT SECTION


Fluoride mg/L <0.1 0.2 1.5

Sulfide mg/L 0.003 0.001

Chromium mg/L <0.023 0.004 0.05

Phosphate mg/L 2.7 0.3

Cuprum mg/L

0.02 2

Hardness mg/L 77 83 500

Chloride mg/L 16 4 250

Organic Matter mg/L 22 3 10

Fecal Coliform Col/100mL 1,600,000 10

4. RBF WELLFIELD DESIGN AND IMPACT ASSESSMENT

4.1 DESIGN

There are 10 wells constructed in the area of Cilandak WTP, at the Krukut Riverbank. Each

well has 6 inches diameter and 30 meters depth. Figure 4.1 below shows the wellfield design

and its piping, while Figure 4.2 is showing the well / borehole design.

Figure 4.1 Wellfield and Pipeline design


DEPARTMENT SECTION


Figure 4.2 Well / Borehole Design

4.2 CILANDAK SHALLOW AQUIFER SIMULATION

An aquifer model was designed in order:

1) to optimize the design of the wellfield

2) to simulate the impact of the wellfield over groundwater levels in Cilandak area.

The model was designed using the software Aquifer Simulation for Windows (ASMWIN 6.0), a

finite difference two dimenssional aquifer model.

The input data were taken from the hydrogeological study.

Wellfield configuration: 10 wells, 15 lps each one

Hydraulic conductivity: 2 x 10-5 m/s

Speciphic yield (aquifer storage): 15%

Krukut River leakeage: 10-4 1/s

Time: Transient condition, until 30 years since start running

WRD & PO

DEPARTMENT

Figure 4.3 Origin of water pumped by RBF wellfield. After less than 3 months of started

pumping, more than 90% of the water will come from Krukut River leakeage.

Figure 4.4. Water levels drawdown after 100 days and 30 years after start pumping. Water

table will On the West of Krukut River the levels will not be affected.

WATER RESOURCE DEVELOPMENT

Riverbank Filtration for Cilandak WTP Raw Water Optimization

water pumped by RBF wellfield. After less than 3 months of started



e West of Krukut River the levels will not be affected.


SECTION


water pumped by RBF wellfield. After less than 3 months of started



WRD & PO

DEPARTMENT

5. COST AND BENEFIT ANALYSIS OF THE PROJECT

5.1 COST

The total CAPEX of RBF Project

a. Drilling wells: 368 MIDR

b. Pumps: 560 MIDR

c. Piping: 372 MIDR

For electricity OPEX raised due to 10 pumps utilization, it will be about

267 MIDR electricity cost year

5.2 BENEFIT

Assumption of combining 250 l/

of parameters, such as Ammonium and Detergent. It will

especially for Chlorine and Activ

For Ammonium, the highest value recorded in 201

water from surface water and wells was resulted not more than

calculation. Figure 5.1 below shows the detail

calculated quality of mixed water


Riverbank Filtration for Cilandak WTP Raw Water Optimization

BENEFIT ANALYSIS OF THE PROJECT

of RBF Project is 1.3 BIDR, with the breakdown below:

MIDR

raised due to 10 pumps utilization, it will be about

MIDR electricity cost yearly. Detail calculation available in Attachment 1

Assumption of combining 250 l/s of Krukut River and 150 l/s of RBF, will decrease some

of parameters, such as Ammonium and Detergent. It will impact on reducing

especially for Chlorine and Activated Carbon.

For Ammonium, the highest value recorded in 2011 was around 3.4 mg/l, while mixing the

rom surface water and wells was resulted not more than 2 mg/l

below shows the detail of raw water quality data in 201

calculated quality of mixed water.


SECTION


raised due to 10 pumps utilization, it will be about 44.2 KWH or about

Attachment 1.

s of RBF, will decrease some

on reducing chemical use

mg/l, while mixing the

mg/l, based on the

of raw water quality data in 2011 and the


DEPARTMENT SECTION


Figure 5.1 Ammonium at Cilandak raw water

The same methodology also applied for manganese quality. For the highest value in 2011,

which was 0.7 mg/l, it could be decreased into 0.5 mg/l by mixing the raw water coming from

the surface water and wells. Figure 5.2 shows the whole data recorded in 2011 and its

calculated mixed water for manganese parameter.

Figure 5.2 Manganese at Cilandak raw water

For Detergent, 2 mg/l had been recorded in 2011 to be the highest value. By mixing the

water from Krukut River and water coming from RBF, the value could be decreased up to

1.3 mg/l. refer to Figure 5.3 for the whole data and mixed water values.


DEPARTMENT SECTION


Figure 5.3 Detergent at Cilandak raw water

5.3 COST AND BENEFIT ANALYSIS

Total investment of RBF Project construction = 1,300,000,000 IDR

Cost of electrical due to pumps utilization = 267,000,000 IDR

Saving is calculated based on the chemicals reduction, data of 2011.

Chlorine saving = 405,979,451 IDR

Activated Carbon saving = 749,218,725 IDR

Coagulant saving = 291,963,591 IDR

KMnO4 saving = 42,285,600 IDR

Total chemical saving = 1,489,447,364 IDR

Total saving = total chemical saving – electrical cost

= 1,489,447,364 IDR – 267,321,600 IDR

= 1,222,125,764 IDR

Payback period of the project is calculated based on the investment divided by total saving:

= 1,300,000,000 IDR / 1,222,125,764 IDR

= 1.06 years

Detail calculation can be found on the Attachment 2.


DEPARTMENT SECTION


6. WELLFIELD CONSTRUCTION

The initial 2 wells, the construction was made in the end of 2010. For the rest 8 wells

was drilled in mid of 2011.

Figures below show the activities during construction.

Figure 6.1 Drilling Activity

Figure 6.2 Coarse Sand Additions


DEPARTMENT SECTION


Figure 6.3 New Well Constructed

7. RBF FURTHER STAGES FOR THE FUTURE

Based on the results given from the Project of RBF at Cilandak WTP, RBF could be useful to

the other places in order to improve the raw water quality. Of course, it will need further

assessment.

For Cilandak in particular, the second stage, after upsizing transmission, RBF water will be

added at the outlet of the Plant in order to increase Cilandak WTP production.


DEPARTMENT SECTION


Attachment 1

Estimation Cost for Electrical Consumption of RBF Pumps

Pump of RBF wells:

For 6 wells use pump with capacity 12 l/s@20, each electrical power is 3.7 Kw

For 4 wells use pump with capacity 15 l/s@20, each electrical power is 5.5 Kw

Power Electricity of the 10 pumps:

For 12 lps � 6 pumps x 3.7 Kw = 22.2 Kw

For 15 lps � 4 pumps x 5.5 Kw = 22 Kw

Total power = 22.2 Kw + 22 Kw

= 44.2 Kw

Estimation of electrical cost is 700 IDR/Kwh

Total estimation of electrical cost for RBF pumps per year:

= 700 IDR / Kwh x 44.2 Kw x 24 hours x 30 days x 12 months

= 267,321,600 IDR / year


DEPARTMENT SECTION


Attachment 2

Table 1 Activated Carbon Saving Calculation

2011 Actual Data Calculation with Mixed Water (Krukut + RBF)

Month Detergent

Avg. (mg/l)

Activated Carbon

Consumption (Kg)

Cost of

Activated

Carbon (IDR)

Detergent Avg.

(mg/l) % Removal

Activated Carbon

Consumption (Kg)

Cost of Activated

Carbon (IDR)

Jan-11 0.4

18,000

131,400,000 0.3 27% 13,074 95,442,568

Feb-11 0.5

20,450

149,285,000 0.3 29% 14,448 105,473,098

Mar-11 0.5

33,000

240,900,000 0.3 29% 23,375 170,637,500

Apr-11 0.2

29,925

218,452,500 0.2 21% 23,582 172,150,068

May-11 0.2

37,800

275,940,000 0.2 19% 30,713 224,201,250

Jun-11 0.3

18,025

217,442,500 0.2 26% 13,378 161,383,105

Jul-11 0.4

17,100

166,170,000 0.3 27% 12,469 121,165,625

Aug-11 0.9

33,500

244,550,000 0.6 33% 22,365 163,264,915

Sep-11 0.4

28,400

207,320,000 0.3 28% 20,553 150,034,211

Oct-11 0.7

25,000

309,700,000 0.5 32% 17,045 211,159,091

Nov-11 0.6

11,150

81,395,000 0.4 31% 7,654 55,875,666

Dec-11 0.7

32,800

430,840,000 0.5 32% 22,336 293,389,179

Total 305,150 2,673,395,000 220,992 1,924,176,275

Activated Carbon

Saving 749,218,725


DEPARTMENT SECTION


Table 2 Chlorine Saving Calculation


Month Ammonium

Avg. (mg/l)

Chlorine

Consumption (Kg)

Cost of Chlorine

(IDR)

Ammonium

Avg. (mg/l) % Removal

Chlorine

Consumption (Kg)

Cost of

Chlorine (IDR)

Jan-11 0.5

14,455 104,798,750

0.32 30% 10,118.50 73,359,125

Feb-11 0.5

13,245 96,026,250

0.35 31% 9,154.63 66,371,085

Mar-11 0.7

14,500 105,124,275

0.47 33% 9,771.74 70,844,620

Apr-11 0.4

12,855 93,200,708

0.28 29% 9,119.02 66,114,252

May-11 0.5

13,545 98,201,250

0.35 31% 9,361.99 67,874,393

Jun-11 0.5

12,500 90,626,233

0.35 31% 8,639.71 62,638,720

Jul-11 0.7

14,300 103,675,653

0.44 32% 9,680.00 70,180,442

Aug-11 1.4

15,800 114,547,463

0.92 35% 10,253.19 74,333,992

Sep-11 1.6

13,050 94,612,863

1.00 35% 8,440.40 61,193,158

Oct-11 2.2

15,350 111,287,500

1.42 36% 9,827.11 71,246,558

Nov-11 1.6

15,750 114,187,500

1.02 35% 10,180.18 73,806,319

Dec-11 1.0

15,250 110,563,588

0.65 34% 10,056.44 72,909,917

Total 170,600 1,236,852,033

114,603 830,872,582

Saving klorin 405,979,451


DEPARTMENT SECTION


Table 3 Coagulant Saving Calculation


Month Raw Water

Volume (m3)

Turbidity

(NTU)

Coagulant

Consumption

(kg)

Cost of

Coagulant

(IDR)

Turbidity

(NTU) % Removal

Coagulant

Consumption (kg)

Cost of

Coagulant

(IDR)

Jan-11 1,057,931 80.3 35,063 59,607,100 50.9 37% 22,242 37,811,513

Feb-11 958,828 70.3 32,204 54,746,863 44.7 36% 20,471 34,800,611

Mar-11 1,049,449 70.7 35,403 60,185,653 44.9 36% 22,502 38,254,404

Apr-11 1,011,999 78.5 36,406 61,890,200 49.8 37% 23,101 39,272,532

May-11 1,043,812 91.4 35,192 59,826,400 57.9 37% 22,284 37,882,256

Jun-11 1,009,513 78.6 42,421 72,115,700 49.9 37% 26,918 45,760,790

Jul-11 1,002,624 67.6 39,429 67,029,198 43.0 36% 25,080 42,636,476

Aug-11 1,038,651 50.0 44,445 75,556,160 32.0 36% 28,445 48,355,489

Sep-11 988,391 72.3 45,418 77,210,039 45.9 36% 28,858 49,057,652

Oct-11 1,066,708 72.4 51,968 88,346,265 46.0 36% 33,018 56,131,226

Nov-11 1,025,331 70.3 36,046 61,277,435 44.7 36% 22,914 38,952,511

Dec-11 1,062,904 71.0 37,266 63,352,685 45.1 36% 23,685 40,264,647

Total 12,316,141

471,261 801,143,698

299,518 509,180,107

Coagulant Saving 291,963,591


DEPARTMENT SECTION


Table 4 KMnO4 Saving Calculation


Month

Manganese

Avg.

(mg/l)

KMnO4

Consumption

(kg)

Cost of

KMnO4(IDR)

Manganese

Avg. (mg/l) % Removal

KMnO4

Consumption (kg)

Cost of KMnO4

(IDR)

Jan-11 0.09

0.13

Feb-11 0.095

0.13

Mar-11 0.111

0.14

Apr-11 0.111

0.14

May-11 0.093

0.13

Jun-11 0.076

0.12

Jul-11 0.127

0.15

Aug-11 0.386 825 39,190,683 0.32 18% 675.98 32,108,946

Sep-11 0.432 926 43,980,298 0.35 20% 739.43 35,123,154

Oct-11 0.524 1,461 69,397,331 0.40 23% 1,122.23 53,306,156

Nov-11 0.335 365.73 17,372,175 0.28 15% 310.46 14,746,902

Dec-11 0.344 1,023 48,607,662 0.29 16% 862.68 40,977,389

Total

4,601 218,548,148

3,711 176,262,549

KMnO4 Saving 42,285,600

river bank filtration experience in south jakarta indonesia

Documents