A product of WRI Ross Center for Sustainable Cities

VITTAL BOGGARAM & RAJ BAGATH

MAPPING, MEASURING AND MITIGATING

URBAN WATER CHALLENGES

Photo Credit: Arnie Papp/Flickr

WHY DO WE NEED IUWM

Image Source – WB, WRI, ToI, UConn

CITY WATER ASSESSMENT TOOL - BENGALURU

Photo Credit: Live Once Live Wild/Flickr

WHERE DOES OUR WATER COME FROM

Image Source – GFW Water, Aqueduct

2800

726

270

17.5

0 500 1000 1500 2000 2500 3000

Total Rainfall

Cauvery River Flow

Karnataka Allocation

Provided for City

Cauvery (TMC)

FUTURE THREATS TO AVAILABILITY

Image Source – GFW Water, KSAPCC

BENGALURU’S WATER

DEMAND

836

372

67

1752

3027

0 1000 2000 3000 4000

Domestic

Commercial and Public

Industrial

Vegetation

Total

Water Demand 2011 (MLD)

• Total = human + vegetation• Human (2011) = 1,275MLD• Human (2017) = 1,595MLD• Vegetation (2014) = 1,752MLD

Photo Credit: Chetiya Sahabandu/Flickr

BENGALURU’S WATER

SUPPLY

1350

-664

686

1611

244

1367

2961

-1000

-500

0

500

1000

1500

2000

2500

3000

3500

Water Availability (MLD)

• Kaveri = 1,350MLD• NRW (49.25%) = 664MLD• Human Supply = 68lpcd• Rainfall = 1,611MLD• Total Available = 2961MLD

BENGALURU’S WATER

STRESS

• Around 2.2million no piped supply (25%)

• Areas outside former BMP area at most stress

• Self provision by buying water or groundwater extraction

Photo Credit: John Loo/Flickr

URBAN RISKS –

LOSS OF WATER RESOURCES

154

11698

30

0

50

100

150

200

1990 2000 2010 2015

Surface Water Loss (sqkm)

• Loss of Surface Water 125sqkm (1990-2015)• Major loss outside BBMP• Groundwater depletion (1,000ft)

Photo Credit: Jonny/Flickr

URBAN RISKS –

LAND SUBSIDANCE

• City is Sinking• City Subsidance – 2.34cm to

3.17cm (average 2.73cm)• Excessive groundwater

pumping• Reduced recharge potential

URBAN RISKS –

VEGETATION CHANGE

• City’s Vegetation Changing (2014-17)

• Loss is higher outside BMP• Loss due to Urbanization• Gain around lakes due to

weeds

URBAN RISKS – HEAT ISLAND &

LST JANUARY 2017

Shanti Nagar Bus Depot Langford

Town

Kalasipalayam

JayanagarLal Bagh

2,601,513

11,072

1,524,389

0

500,000

1,000,000

1,500,000

2,000,000

2,500,000

3,000,000

Above Mean Extremetemperature(above 34)

1 DegreeIncrease

People Exposed to Heat in Jan 2017(C)

• LST 2014-17• Change in temp +8C and -10C• North, west and south-west

getting hotter• South and south-east cooler.

URBAN RISKS – LST CHANGE

URBAN FLOODING – DYNAMIC MODELS

Photo Credit: Thomas Leuthard/Flickr

URBAN FLOODING –

ANALYSIS

138,249

29,994

Urban Flooding

Population in Begur and Arakere wards

Population facing stagnation / flooding in Begur andarakere wards

• Begur & Arakere Wards• 10cm for 5 hours• 1,40,000 population• 30,000 Impacted

CITY SANITATION WATCH

– OPEN DEFECATION

2011 Data – 1,33,913 OD

Photo Credit: McKay Savage/Flickr

CITY SANITATION WATCH –

PIPED SEWER NETWORK

2million no access to piped sewer

CITY SOLUTIONS

Photo Credit: Diego Torres Silverstre/Flickr

BENGALURU’S

WATER BALANCE

WATER REUSE POTENTIAL –

K&C VALLEY STP

Defence

K&C Valley STP

HAL Airport

Bellandur Lake

CHIKKABALLAPURA MASTER PLAN 2031

LAKE REVIVAL – ‘KERE’ PROJECT

Design Credit: Rajeev Malagi

WATER SENSITIVE URBAN DESIGN

Design Credit: Rajeev Malagi

WAY FORWARD

THANK YOU FROM WRI INDIA

Vittal Boggaram Sahana Goswami

Raj Bhagat

V Surya Prakash

Radha Chanchani