Monday, 13 January 2020

Can we protect our precious ground water on the sea cost of over 7500 kilometers of Indian cost line?


Can we protect our precious ground water on the sea cost of over 7500 kilometers of Indian cost line?

Our country - India is one of the richest country with its natural resources - gift of nature
India has over 7500 kilometres long sea cost and has the most fragile ecosystem. Ground water extraction along the sea cost has encouraged saline water intrusion to several kilometres inland. Ground water being the major source for domestic as well as industrial use has touched alarming levels of TDS. Water softeners and largescale water treatment plants are the order of the day for both domestic and industrial water requirement (unsustainable)
It is time we take scientifically correct and simple measures to harness rainwater and protect our ground water- Sustainable management


Ganjam, Odisha - Case study of Grasim Chemicals

Water pumped                                          2360 kld
Water supply on the way to villagers         500 kld
Water used in the plant                            1860 kld
Raw Water Quality TDS                            2600
Annual Rainfall                                         1238 mm



Road side drain to collect rainwater

Cement ring well infiltration gallery
Roof top rainwater from most of the buildings in the colony is harvested and being recharged in to the ground.
RainTap RoofWater filters are mounted on the wall to filter roof top rainwater from the buildings and used rainwater is used for domestic needs as the rainwater is purer than any other source in the colony.
Accelerated recharge wells


Testing of percolation of water through recharge wells 



















Large scale ground water recharge at the ‘Rushikulya’ river bank:

Three borewells of diameter 300 mm at depth of around 46 meters are the source of water on the bank of Rushikulya’ river.
Only two borewells are being used at present. The third borewell is not in use and is sealed from the top.
The percolation pond near the borewells has around 30,000 sqm catchment area and impound water by creating an impervious bund using HDPE liner. Recharge of rainwater through sub soil and augmented by drilling two recharge shafts with perforated / serrated casing pipe to a depth of 40 meters. The third borewell which is not in use is also in the water impounding area close to the bund. This borewell can also be used to recharge water as this is not being used to with draw water.
Perforated pipe ground water recharge shaft

HDPE lined rainwater collection pond for high volume groundwater recharge


To enhance the ground water recharge capacity, additional catchment of around 90,000 sqm area is developed near the pump house and the care taker house. Two impounding bunds with HDPE lining are created to form two separate ponds to collect rainwater.

As the catchment areas have water flowing in different directions, few channels are dug to lead the rainwater towards ponds with impervious bunds.

Water harvesting in the open field of the Grasim colony is established by creating precast cement ring wells for accelerated ground water recharge. The rainwater collected in the box type drain is intercepted at intervals and the water is diverted to the recharge wells created next to the drain.



To create awareness for water conservation and rainwater harvesting, over 30 schools are identified and the surface runoff from the playground and surrounding area of the school buildings is diverted to precast cement ring wells for accelerated ground water recharge.



Wednesday, 1 January 2020

Rainwater Harvesting Act 2009, 72 A - BWSSB


THE BANGALORE WATER SUPPLY AND SEWERAGE (AMENDMENT) ACT, 2009

“72A. Obligation to provide rain water harvesting structure

Within nine months from the date of commencement of the Bangalore Water Supply and Sewerage (Amendment) Act, 2009 every owner or occupier of a building having a sital area of 2400 square feet and above or every owner who propose to construct a building on a sital area of 1200 square feet and above shall provide for rain water harvesting structure in such manner, with such conditions as may be provided in the regulations failing which the Board may cause such rain water harvesting structure and recover the cost from the owner or occupier, as the case may be, arrears of land revenue.”

BWSSB Guideline for Rainwater Harvesting (RWH)

Minimum Requirement:

Rainwater storage (surface tank or underground sump) and ground recharge (RCC precast ring well) of minimum 20 liters per square meter of roof area and a minimum of 10 liters per square meter of paved open space provision shell be made. The open well / recharge well of depth of 3 meter (minimum) and diameter of .9 meter (minimum) with out filling in the well (like aggregates, jelly, sand etc.) provision shell be made.

You may store rainwater in a tank / sump or recharge rainwater in to the ground through a well or you can use a combination of these two to achieve the stipulated capacity of ‘X’ liter. Where X = roof area in sqm x 20 + paved open area in sqm x10.

The open well should be of minimum 3 ft diameter and 10 feet deep.
Ground water recharge should not be attempted at places where the ground water level is very high and at places where hard rock strata exists at shallow depths. It is suggested to build a shallow sump or install a surface tank for storing harvested rainwater.

Rainwater from the roof and through a filter should not be allowed directly in to a live borewell. It is advisable to allow the filtered rainwater in to an open well beside the borewell. In case of a failed or very low yielding borewell, you may allow a portion of overflow from your tank / sump which collects filtered rainwater from the roof. However a skilled person’s advice is required before recharging the borewell directly.



Government of India, Film Division presents 'Rain Man'