Chennai is going through water scarcity. The city faced two consecutive monsoon failures and major sources of water are dry.
Various Reasons for the Water Scarcity:
- In 2017 and 2018, the state had received deficit rainfall.
- In 2018, Chennai received lowest rainfall of 75.55 cm as against 149.5 cm in 2017.
- Due to deficit rainfall, the four major reservoirs – Chembarambakkam, Cholavaram, Poondi & Puzhal – that supply water to Chennai, were dried.
- The heat wave in this summer in Chennai made the situation worse.
- The city does not have perennial water source.
- The four main water reservoirs are currently at less than one percent of storage level.
- Loss of many water bodies in the city.
- Coovum and Adyar rivers are polluted.
- Urban sprawl continues to occupy more space and hence the water bodies shrink.
- Urbanization is the major reason for encroachment of water bodies and mixing of sewage with city’s rivers and lakes.
- Due to increase in population, encroachments taken place in the city.
- Constructions close to the water bodies taken place illegally
- Lack of rainwater harvesting
- Lack of awareness among people
Steps Taken by the Government
- Everyday 525 MLD of water is being distributed in the city.
- Abandoned quarries are utilized to draw and supply water to the public after testing and treatment of water.
- Tanker lorries are used to supply water throughout the city.
Metro Water Tankers
Chennai metro water acquires water through pipelines and tankers from Veeranam tank, Retteri Lake, Neyveli Acquifer and Minjur & Nemmeli desalination plants.
Private tankers acquire water from agricultural wells and borewells.
Water from Quarries
Water is taken from quarries in Sikkarayapuram near Mangadu and also from Erumaiyur quarries. Then the water is conveyed through pipeline to a water treatment plant in Chembarambakkam. Then the water is treated and distributed to Mogappair distribution station. Finally, the water is pumped from Mogappair station through pipelines and lorries.
Two more plants to treat sewage
- Chennai Metro water set up two more tertiary treatment reverse osmosis plants to treat sewage and supply to industries.
- The two plants in Koyambedu and Kodungaiyur with capacity to treat 15 million litres of sewage daily each.
Under this scheme, common people and local farmers were involved in cleaning up the lakes. The desilting work would be carried out in 1829 lakes during 2019-20 and fund of Rs. 499 crore has been allocated for this purpose. In Chennai, desilting work would be carried out in four reservoirs.
Chennai received its first water train from Vellore district on July 12, 2019. The train carrying 2.5 million litres in 50 wagons, covered 200 km from Jolarpet to Villivakkam in four hours. Chennai received its first train -load of water after a gap of 18 years. From Villivakkam railway station, the water will be distributed across the city.
Grey Water Recycling
Grey water recycling made mandatory for industries. Permission will be granted to new industries and multi-storey building only if they commission grey water recycling plant.
Desalination plants at Minjur and Nemmeli use the reverse osmosis drinking water supply.
Sustainable Solutions For Water Problem:
- Rainwater harvesting will help to conserve water for future use.
- Committees formed with officials from Chennai corporation and Metro water to develop rainwater harvesting facilities. Technical guidance will be given by officials on rainwater harvesting at residents. The rainwater harvesting potential for a terrace of 1000 sq.ft house is 1.2 lakh litre.
Development of Technology
Agriculture and Industries are the major water consumer. New technology should be developed in such a way to reduce their consumption.
Treated sewage water can be used for flushing toilets, AC systems and running ventilation.
Conservation of Floodplains
Construction activities must be avoided on the floodplains
- Desalination of seawater can be done for obtain drinking water.
- In this process, the seawater is first treated for removing suspended solids. Then, the disc filters and ultrafiltration membranes are used to remove sediments and finer sand particles from water. Then the sea water flows through reverse osmosis membrane which removes salinity and reduce the level of total dissolved solids at 500 ppm
- Then, the treated seawater is sent for re-mineralizing, with carbon dioxide and time to make it fit for consumption. Finally, it is conveyed to sump for distribution.
Restoration of old rivers:
- Restoration of Coovum and Adyar rivers will help to sought out water scarcity.
- The Chennai River Restoration Trust and Chennai metro water would prepare project report for restoring the polluted waterways in the city. The project report will give proposals to arrest sewage pollution, construction of sewage treatment plants and strengthening sewage network in the city. It would look for ways to establish a dedicated grid for recycled water.
Jal Shakti Abhiyan:
- The Central government launched this scheme on July 1, 2019 to promote rainwater harvesting and conservation efforts in over 1500 blocks in 255 water stressed districts.
- The Central government officials monitor the programme with intervention areas such as intensive afforestation renovation of traditional water bodies, reuse and recharge structures and watershed development.
Water Resources Conservation and Augmentations mission:
The State Government announces “Tamilnadu water resources conservation and Augmentation Mission”, a people’s movement in order to conserve and manage water. The work will be carried out through the National Rural Employment Guarantee scheme at the cost of Rs. 750 crore.
Preventing Water Pollution:
“Nadanthai Vaazhi Cauvery” project which aims at preventing the Cauvery from getting polluted. The government assures to take steps to prevent pollution of Bhavani, Vaigai, Amaravati and Thamirabarani.
Trees can save the city from the impact of extreme weather. Their root structures absorb water, preventing flooding and the stored water will be helpful during drought. Plants help in bringing rain.
Awareness and education:
Awareness and education on water scarcity should be increased. There are lots of people who are unaware of the reality of water scarcity. People must be educated to conserve water.
Prevention of encroachments on water bodies:
- Due to encroachment, lakes area was reduced. In order to identify lake areas and boundaries, boundary stone should be laid permanently and the encroachers should be moved to another area. This will help in increasing the area of waterbodies.
- The way forward is to ensure ground water recharge and preserve waterbodies. The protection of water bodies will help in sustaining groundwater recharge and also prevent flood. Preventive and sustainable actions should be taken for future.