Wastewater recycle and reuse:

The need of the hour Workshop

Date: 18 April 2012,

Ministry of Urban Development, Govt. of India

Uday G. Kelkar, Ph.D., P.E., BCEE

M. N. Thippeswamy, Chief Engineer (Rted), BWSSB

Experience of Bangalore in Reuse

– Lessons Learned

GoK has allocated 600 cusec or 17 Cumecs (1469 Mld) of raw water from Cauvery River to BWSSB, with CWSS Stage IV - Phase I commissioning, raw water drawl is about 929 Mld

Balance raw water available is about 540 Mld

Raw Water (Mld) from Cauvery river

Stage I ( 1974) : 150

Stage II ( 1982) : 150

Stage III ( 1994-95) : 314

Stage IV Phase I (2002) : 315

Stage IV Phase II : 540

Total Abstraction 1469

Source Availability

Water Sources for Bangalore City

Projected Water Demand and

Availability of Fresh WaterBBMP AREA

Year

Population

Million

Demand

in MLD

Available

MLD

Shortfall

MLD

2001 5.4 870 540 310

2007 7.5 1219 840 379

2015 8.8 1720 1500 220

2021 10 2125 1500 615

2036 12.5 2550 1500 1050

Population figures as per CDP

Wastewater Treatment

Number of Wastewater

Treatment Plants

12 (Including 2 Tertiary

Treatment plants)

Total Installed Capacity 718 MLD

Quantity of treated

wastewater

350 MLD

Quantity of usage of

treated water

4 MLD (Supplied to

International Airport, BEL etc.

Treated effluent flowing

into the valleys

346 MLD

Integrated Water Resource

Management

Reuse of Wastewater from

Vrishabhavathi Valley,

Bangalore

UF/GAC Plant

Upgradation of

T.G. Halli WTP

V-Valley –

180+120 MLD

Mailasandra

75 MLD

Kengeri – new

120 MLD

Chodanapura

New 20 MLD

Bangalore City

V-Valley Reuse

T.G. Halli

Reservoir

To Byramangala

Tank

Proposed V. Valley STP Process

Primary

Treatment

Initial

Future

180

MLD Secondary

Treatment

Existing

Tertiary30

MLD

150

MLD

New

Tertitary

To other

reuse

(30 MLD)

To

Tavarkere

(150 MLD)

To other

reuse or

river

(30 MLD)

120

MLD

Down rated to 30 MLD primary effluent

Primary

Treatment

120

MLD Secondary

Treatment

120

MLD

New

Tertitary

To other

reuse or

river

(30 MLD)

120

MLD

Recycle and Reuse of Raw Sewage forRecycle and Reuse of Raw Sewage for

Indirect Potable Use Indirect Potable Use –– Process Flow Process Flow

(Water management scheme in V and K&C Valley)(Water management scheme in V and K&C Valley)

STPs under JBIC

Project with

Nitrification/De-

Nitrification

Tertiary Treatment

as separate add-on

for Phosphorus

removal

Travel in Water

Course for a min of

40 Kms for natural

freshening

Ultra-Filtration

Membrane Treatment

for Entero Virus

Removal

Pumping to Raw Water

Reservoir Site

Further Treatment

through WTP with

Filtration and

Disinfection of

water

Finished Water for

Distribution

Pumping to Fresh

Water Reservoir

Site

Mixing with Raw Water

Reservoir

• 135 MLD of tertiary treated water after chlorination is

pumped to Tavarekere over a 23 km distance.

• This water is is further treated using Ultrafiltration (UF)

followed by Granular Activated Carbon (GAC) process to

produce water that is free from all microbial and viro-

logical contaminants at Tavarekere

• This water is then discharged into Arkavathy River for a

travel of 7 kms for Natural purification and Assimilation

before mixing it with the Existing T. G. Halli reservoir

source. This water will serve as the raw water source for

T.G. Halli WTP

• The Existing T.G. Halli WTP will be renovated using

membrane filtration processes to produce 135 MLD of

potable water which is pumped to Bangalore City.

Process

Proposed Indirect Potable use -

Bangalore

135 MLD Reuse Process Scheme

STP

Raw

Sewage

TTPUpgraded

Tertiary

Treatment

Plant

Pumping

Station

Wastewater

Treatment Plant

(BNR)

23 Kms, 1300 mm

diameter MS pipe.

70 MLD (150 MLD)

Break

Tank/Cascade

Aerator and

micro-strainer at

Tarverkare

75 MLD

(150 MLD)

UF

Backwash

/reject

Ultrafiltration (UF)

Plant 70 MLD (145

MLD) Break Tank

After UF

Plant

High rate settler/UF

to recover

backwash water

Waste to Lagoon

Granular

Activated

Carbon (GAC)

filters

GAC Backwash

Treated water

sump

Cl2 addition

(for residual

maintenance)

Cl2 addition

(Super

chlorination)

Arkavathy

River

7 Kms

Inlet to T G

Halli Reservoir

Raw Water

UF

Reservoir

Reverse

Osmosis (RO)

Cl2 addition

To BWSSB

Distribution System

(pumping)

V-valley Plant

Premises Tarverkare

Upgraded T G Halli WTP

Dam

Reclaimed water

Kum

udavath

i Riv

er

67.5 MLD

(135 MLD)

45 MLD

(85 MLD)

25 MLD

(50 MLD)

70 MLD

(140 MLD)

67.5 MLD

(135 MLD)1

2

34

Bangalore Pilot Experience

Test Report no. → 69683-08 49166-08 68498-08 30424-08 13803-09 25548-09 17203-09 76756-09 18284-09 74339-09

Units December January February March April May June July August Septembe

r

1 pH - 6.8 7.3 7.7 7.6 7.6 7.4 7.3 7.2 7.2 7.4

2 Total Suspended Solids mg/l 133 123 132 102 117 109 236 188 168 110

4

Total Kjeldahl Nitrogen

(as N) mg/l 28.28 42.28 35.84 36.96 39.48 34.44 36.4 37.8 65.8 72.8

5

Ammonical Nitrogen (as

N) mg/l 4.21 30.82 26.82 24.53 24.77 20.36 24.91 29.59 24.55 28.52

7 Total Dissolved Solids mg/l 814 732 768 760 772 768 806 932 756 836

8 BOD3 at 27°C mg/l 270 144 84 132 120 162 135 144 102 138

9 COD mg/l 460 380 230 430 380 540 470 490 330 420

10 Iron (as Fe) mg/l 1.93 4.2 8.3 4.84 6.24 4.682 0.551 0.488 4.59 1.97

11 Manganese (as Mn) mg/l <0.051 <0.051 < 0.051 0.29 0.383 0.25 0.24 0.23 0.24 0.326

12 Carbonates (as CO3) mg/l 0 0 0 0 0 0 0 0 0 0

13 Chlorides (as Cl) mg/l 111.97 84.97 94.97 104.97 119.96 109.97 139.96 174.94 113.96 129.96

14 Fluorides (as F) mg/l 0.133 1.66 0.435 0.295 0.323 0.378 0.869 0.971 0.839 0.76

15 Hydroxides (as OH) mg/l 0 0 0 0 0 0 0 0 0 0

16 Nitrites (as NO2) mg/l 0.132 0.071 0.014 0.057 0.062 0.57 0.08 0.048 0.018 0.023

17 Sulphates (as SO4) mg/l 0.91 36.13 21.49 24.16 28.66 27.27 31.12 30.61 21.9 24.87

18 Sulphites (as SO3) mg/l 63 24 9 9 12 18 21 27 66 84

19 Calcium (as Ca) mg/l 78.4 56 48 56 64 60 60 76 51.2 57.6

20 Magnesium (as Mg) mg/l 9.6 24 24 24 24 26.4 19.2 21.6 16.32 18.24

21 Selenium (as Se) mg/l 0 0 0 0 0 0 0 0 0 0

22 Silica (as SiO2) mg/l 16.48 25.19 32.59 29.85 30.59 28.3 31.41 28.22 28.7 31.63

23 Barium (as Ba) mg/l 1.08 0.541 < 0.18 0.541 0.631 1.89 0.721 1.17 <0.18 4.14

26 Faecal Coliforms /100ml >1600 >1600 > 1600 > 1600 >1600 >1600 >1600 >1600 >1600 >1600

27 E.coli CFU/ml UC 140 UC UC 41 43 194 118 104 134

Average values over 12 month period

Parametereffluent from V-

Valley Plant

Tertiary Treatment

Plant output Arkavathy River 7 Kms before meeting T.G. Halli Reservoir

BOD mg/L 22 1.6 12

COD mg/L 65 8 27

Sulfate mg/L 24.7 13 86.18

Magnessium 28 19 62.5

Phosphaste mg/L 1.8 0.6 2.8

Ammonia mg/L 25 5 8

TDS mg/L 450 228 320

Fecal Coliforms/ 100 mL > 1600 2 > 1600

Ecoli/100 mL >400 3 >600

PROJECT COSTNo. Work

Rs.

Crores

1 Lifting of V Valley water for biological treatment (BNR), tertiary

treatment utilising by upgrading existing facilities of 60 MLD TTP 98.00

2 Pumping station for pumping tertiary treated water to Tavarekere –

Civil, Electrical and Hydro Mechanical 25.98

3 Substations and electrical systems at V valley 6.20

4 Pumping station for transferring water to Tavarekere 25.00

5 Pumping main from V valley to Tavarekere 46.15

6 Inlet micro-straining, U F Plant, GAC at Tavarekere, 135 MLD

capacity 135.00

7 Gravitation pipeline to Arkavathy river 2.12

8 Arkavathy River course protection 2.10

9 Rehabilitation of TG Halli WTP with Ultra filtration and Reverse

osmosis and pumping mains to city 102.00

10 Sub total 442.55

11 Contingencies at 3% 13.27

12 Administrative charges at 0.5% 2.21

13 Design and basic engineering at 1.0% 4.42

14 Statutory clearances at 2% 8.85

15 Total 471.33

Suggested Financial Model for Project ImplementationSuggested Financial Model for Project Implementation

Contractor

SPV

Water Board,

Stakeholders and

others

Recycled Water

Revenue

Stakeholders

Equity

Financial

Institutions

Govt./

Donor Grant

Cost Comparison

Present Landed Water Cost (Cauvery Water)

24 Rs/kL

Cost of High quality treated water from V-valley to

Arkavathy River

12 Rs / kL

Contract type – take or pay at the Arkavathy River

Discharge Point. - Payback to BWSSB in 8 years,

Time Horizon

Survey, Preparation of Bid Documents,

Pre Qualification: 3 Months

Tender Call and Award 4 Months

Construction and Commissioning 18 Months

Present Status:

1) Development of Public Participation Program,

Outreach program

1) DPR, Bid Document and Pre-qualification is

complete.

THANK YOU