Understanding Saul Kere

This document attempts to understand the cascading lake system around Saul Kere, its current state, its biodiversity, and its influence on the water system of Bengaluru.

1. Saul Kere and the urban flooding of September 2022
•The cascading tank system of Bengaluru has lost its original identity (as a water source for irrigation) in the current urban context.
•The urban flooding that occurred in September 2022 has been attributed largely to the ignorance of this system.
•Saul kere was identified as one of the lakes where the flooding issue escalated onto the outer ring road and Sarjapura road.
•On 30
th
September 2022, Biome team along with MAPSAS and others went around Saul Kere to survey this issue and subsequently
find possible solutions to avoid such disasters in the future. This document outlines the finding from that undertaking.

2. Saul Kere in 2002
Kaikondrahalli lake
Command Area
Constructed area
•This map shows the Saul
Kere area in 2002.

•The command area for the
lake is roughly mapped.

•A constructed area within
the lake can be identified in
2002 which was later
cleared.
Google Earth Image 03/2002
Bellandur Lake

3. Kaikondrahalli Lake
Bellandur Lake
29 Feet wide
Saul Kere in 2002
•Map shows the presence of two outlets
(White Line) downstream of the Saul
Kere through the command area.
•Yellow arrows represent the water flow
direction.

1.Waste weir Outlet – North west
corner of the Lake
2.Sluice Gate Outlet – From the
north side of the Lake (center of the
Lake Bund)

•These Kaluves were measured on Google
earth to be approx 29 feet wide (as wide
as Primary Kaluve or Raja Kaluve)
Saul Kere
Google Earth Image – 09/2002

4. Kaikondrahalli
Bellandur
Saul Kere in 2022
•Currently, in 2022, the Waste
weir (Kodi) outlet and drain is
functioning (marked in Green)

•The Sluice gate outlet (marked
in white) is absent.

•The yellow Arrows represent
the flow direction of the drains.
Google Earth Image - 02/2022

5. Saul Kere
Bellandur Kere
Varthur Kere
Saul Kere’s
watershed
Natural Drainage and
Watershed
of Saul Kere
The Map shows the natural
drainage networks (lines in
shades of blue) and the
entire watershed (area
marked in light Blue) of the
Saul Kere.


The drainage of the
watershed is produced using
ASTER Digital Elevation
Model - satellite Data
Kaikondrahalli Kere
Halanayakanahalli Kere
Doddakannalli Kere

6. Saul Kere
watershed
Detailed natural
Drainage networks
Of
Saul Kere

The Map shows a very
detailed natural drainage
networks (lines in shades of
blue)

The entire watershed (area
marked in Pink) of the Saul
Kere.


The drainage. watershed is
produced using ASTER
Digital Elevation Model
satellite Data
Saul Kere
Bellandur Kere
Varthur Kere
Kaikondrahalli Kere
Halanayakanahalli Kere
Doddakannalli Kere

7. Saul Kere
Bellandur
Saul Kere
Zoomed in Map for
the detailed natural
drainage network
pattern in and
around Saul Kere
area.

8. Outlet
Inlet
Inlet
Inlet
Inlet
Inlet
Saul Kere
Current Inlet and Outlets of Saul Kere

9. Outlet
Inlet
Inlet
Inlet
Inlet
Outlet
Saul Kere
Natural Drainage Inlets and Outlets of Saul Kere using Digital Elevation Model data.
•Map represents the
natural inlets and
outlets of Saul kere.

•Yellow arrows show
the direction of flow.

•The outlet Marked in
Yellow circle was the
sluice gate outlet
that existed in 2002,
because the
downstream was a
command area for
irrigation.

10. Data from Dishank App.
for Saul Kere
A part of the Kere is marked
as Private Property
No Drains or Outlets mapped in
the downstream of Saul Kere
Saul Kere

11. Consolidated –
revised Master Plan
2015 Map

Proposed Land use
Map
Saul Kere Region

12. Legends
Green – Eco Sensitive Zone
Blue line – Stream/Drain
Saul Kere
Zoomed in Master plan 2015 Saul Kere Region:
The revised master plan of Bangalore 2015 demarcates the Saul kere’s downstream as an Eco sensitive
zone, but Kaluve or storm water drains are not mapped.

13. Observations from field visit on existing condition of Saul Kere and its drain

14. Proposed drainage work after the floods happened between soul kere and Bellandur lake
Proposed SWD in red line Proposed Retaining wall in red block

15. Saul Kere Area:
O.233 Sq km = 23.33 Ha = 57.65Ac
Watershed area:
11.08 (left) + 12.59 Sq km(Right)
= 23.67Sq km = 2367ha = 5848Ac

Land Use Type: (Approx)
Left watershed:
Total Area: 11.08 sq km
Green: 01.63 sq km
Urbanized: 9.45 sq km
Right Watershed:
Total Area: 12.59 sq km
Green: 04.282 sq km
Urbanized: 08.31 sq km
Spatial Data - Area, Land use Land cover type

16. Spatial Information
Elevation change:

Watershed left: 930m to 870m
Watershed right: 910m to 870m
930
920
910
900
890
880
870
910
900
890
880
870
930
920
910
900
890
880
870
Halanayakanahalli
Doddakannalli
Parappana Agrahara
Kaikondrahalli

How many lakes are draining
= Approx 13 lakes
9 (left watershed) + 4 (right watershed)

17. Apart from looking at the Saul Kere from Hydrological, Flood mitigation and Socio-economic
perspectives, it is home to more than 205 Bird species including several migratory birds, and
more than 517 species of insects and animals.

Links to Ebird and Inaturalist websites:
•No. of birds recorded to be seen in Saul Kere: https://ebird.org/hotspot/L5643010
•The time of a year when certain species of bird visit Saul Kere:
https://ebird.org/barchart?r=L5643010&yr=all&m=
•Other insects and animal:
https://www.inaturalist.org/observations?nelat=12.92191845728196&nelng=77.68370847406574
&place_id=any&subview=map&swlat=12.915183970911295&swlng=77.67658452692218

Biodiversity at Saul Kere

18. 1.Major identified Issues:
•Choking - Saul Kere’s Outlet bottlenecks at outer ring road, consider choking due to solid waste
•Increasing the elevation of the downstream area of saul kere where goat grazing people stay.
•Narrowing of the Outlet from Bellandur to Varthur
•Absence of drain from Halayakanahalli Kere causes sheet flow flooding in Sarjapur road

1.Potential Interventions:
•Flood modelling for Saul Kere Area
•Calculate amount of water saul kere can retain to mitigate floods
•Constant monitoring and controlled release of water from Keres in pre monsoon so Keres can
retain water from post monsoon rainfall

1.Things to further investigate:
•Survey the new 800 mm drain pipe at Sarjapura road near Rainbow Drive
•Examine the Elevation change where saul kere outlet meets the outer ring road area
•Reconnaissance survey of Hallanayakahalli Kere (why lake is not filling?)
•Why there is increase in flow from Upstream Lakes of Saul Kere?
•Examine bund strength before Desilting Saul kere and Kasavanahalli Kere
Potential interventions and Things to be cognizant of:

19. 1.BBMP is looking to expand the choke points, namely
●Choke point-1 on NR Layout road
(approx GPS coordinates: 12.921780, 77.677995)
●Choke point-2 on ORR service road, bordering Adarsh Palm Retreat
(approx GPS coordinates: 12.927026, 77.679424)

1.Given the change in rainfall pattern, rainfall intensity and increase of paved and concrete areas, will the
expanded drains be sufficient to drain the area in a short period of time and avoid flooding?

1.Calculation of total runoff from the Saul Kere watershed and Flood modelling would help and better
understand mitigation measures if required.

Pointers after Saul Kere Survey

20. Drains Width:

•Primary Kaluve = 22+ Feet
•Secondary Kaluve = 16 to 22 Feet
•Tertiary Kaluve = 6 to 9 Feet
Buffer Zones for Kaluve:

•For Primary Kaluve = 50m
•For Secondary Kaluve = 25m
•For Tertiary Kaluve = 15m
Miscellaneous information