Kristal Halite apartments in Bellandur implemented rainwater harvesting and water metering.

1. KRISTAL CAMPUS II:
INTEGRATED WATER
MANAGEMENT
Best Practices in Water Management in the Urban
Residential Sector

2. Background
■ Gated community on Sarjapur-Bellandur Road
■ 3 apartments (Halite I, II and Brookite) with a total of 96 individual units
■ No access to BWSSB water supply
■ Access to sewage disposal system, flows into Bellandur STP
■ Water demand is met mainly through tanker supply (40KL per day)
■ 2 borewells on site, only 1 yielding water (10-12KL per day)
■ A third borewell was being dug at the time of the visit
■ Total depth of bore is 1480ft, with water being struck at 1000ft
■ Estimated yield of new well is 36KL per day

3. Approach
■ Kristal residents employ a simple and efficient approach to water management
Water
Sub-metering
• Record individual household usage
• Early leak detection
• Billing transparency
Rainwater
Harvesting
• 80% coverage of rooftop area
• Ground-level filtration
• Storage and reuse

4. Sub-metering
• One of the major tasks of the sub-metering exercise was
the pipeline retrofitting.
• The existing metal plumbing was being retrofitted with
CPVC at the time of the visit.
• In order to replace the aging, encrusted metal pipes
• Ensure adequate flow to the water meters.

5. Deposits in old metal pipes

6. Sub-metering Layout
• A large delivery line carries water from the Overhead Tank to individual sections
of the building
• This line is then split and metered according to the number of apartments in
that section.
• The metered line is laid then out in a ring along the parapet wall
• Splitting off to service bathroom and kitchen areas through the existing
plumbing ducts.

8. Rainwater Harvesting
• The building was constructed such that individual roof sections drained into a common
vertical down-pipe
• At the ground level these pipes were sloped to the back of the building
• The individual down-pipes were joined to a large 6 inch pipe
• The water then travels through a gravel filter system
• A first flush mechanism is provided prior to the filter unit
• The filtered water flows into the 90KL main sump
• A heavy rain results in savings of 20-30 KL litres (Rs. 2,000-3,000 in tanker costs)

9. Rainwater down-pipe
Filtration System
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First-flush valve

10. Valve to be closed during maintenance
and first rain flushing
The filter is an interconnected 2 chambered unit with gravel and activated
carbon used as filter media
The size of each chamber is 2ft*2ft*2ft
Details of Filter Unit

11. Building Manager’s Perspective A word from the plumber
Sub-metering
• Ensures efficient water use
• Better management of water assets
• Accountable and transparent billing
RWH
• Reduces tanker dependency
https://www.youtube.com/watch?v=CBje3tQW5vw&feature
=youtu.be
Benefits of sub-metering
• Lesser wastage
• 20-30% water savings
• Low maintenance
• Avg. cost of 13-16k per flat
https://www.youtube.com/watch?v=xd0h6F
LQAw4