Rain Water Harvesting System at Rain Water Harvesting System at Brigade MilleniumBrigade Millenium

(Cassia Block)(Cassia Block)

- Shankar Rao. Refurb India.- Shankar Rao. Refurb India.(refurb_india@yahoo.com)(refurb_india@yahoo.com)

As presented in “The Water Workshop for Apartment Communities” Organized by ApartmentADDA.com

• One of the earliest high rise apartment blocks in South Bangalore.

• The 5 blocks named after flowers:

Cassia

Mayflower

Magnolia

Laburnum

Jacaranda

• All 16 storey-tall with roof catchment of 2200 sq.m except for Laburnum.

• Today’s presentation is about :

CASSIA BLOCK

Rainwater Disposal – Rainwater Disposal – Pre RWHPre RWH

• Roof top water from 15th/16th floor.

• Down pipes 27 nos. led down chutes in the building center to Basement.

• Down pipes connected to 7 exit pipes.

• Rainwater flows out to Municipal drain/STP/open wells.

FLOW CHART – STORE & USE

FLOW CHART – STORE & USEFLOW CHART – STORE & USE

The ChallengeThe Challenge• Topography of Cassia not conducive for

direct flow to ground sumps.

• Necessitates pumping from Basement level.

• Transit storage became mandatory.

• Rains – unpredictable in timing, duration and intensity.

• Manual monitoring/Control/Action undependable.

The Solution - The Solution - Fully automatized systemFully automatized system

PHASE I:

Programmable logic control to start/stop pumping depending upon flow/storage status.

The Solution - The Solution - Fully automatized systemFully automatized system

PHASE II:

Action to meet the following ‘what if’ emergencies:• Filter block leading to Column Water Build-up.• Basement tanks full & ground sumps full and

rain continues.

The Solution - The Solution - Fully automatized systemFully automatized system

REMEDIES:

• Bypass valves made to change flow status.• Manual intervention for the above ruled out.• Self-operated mechanism activated – How?

The Solution - The Solution - Fully automatized systemFully automatized system

INNOVATIVE HYDRAULIC ACTIVATION SYSTEM:

• No electric power is required, hence no dependence on power supply.

• Water pressure available from roof top tank invoked.

The Solution - The Solution - Fully automatized systemFully automatized system

MECHANISM EMPLOYED:

A) Incase of tank overflow,

a float valve moves up &

opens water flow from roof top.

This action hydraulically moves

the bypass valves appropriately.

The Solution - The Solution - Fully automatized systemFully automatized system

B) Incase of a Filter block,

hydrostatic pressure builds up,

activating a spring-loaded lever,

thus opening the inlet valve;

Pressure activates hydraulically

to move bypass valves to

appropriate position.

Rainwater UtilizationRainwater Utilization

• BWSSB stipulates 70-75% water utilization from roof top catchment.

• Open paved catchment – no stipulation.

CATCHMENT AND RAIN YIELD AT CASSIACATCHMENT AND RAIN YIELD AT CASSIA

TypeTotal area in

sq.mStorage &

use RechargeTotal

harvested % Used

A B C B+C

Roof top 2200 1870 210 2080 95

Paved open 2800 0 1440 1440 51

Unpaved 687 0 500 500 73

TOTAL 5687 1870 2150 4020 72

Rainwater UtilizationRainwater Utilization

Shankar Rao. Refurb India.refurb_india@yahoo.com

80-4173 7584http://www.refurbindia.com/