As the institute community experiences water shortage, Nishant Prabhu assesses the situation and suggests measures to be taken.
Causes and Issues
The northeast monsoon having failed to replenish Chennai‘s reservoirs, the city is staring at yet another, perhaps worse, water crisis after 2017. Before the beginning of this year, Chennai was facing a rainfall deficit of 24%, which has now risen to over 54%. As of January, less than 14% of water was available in water resources in and around the city.
Though the primary cause of this crisis is the diminished rainfall, officials of World Resources Institute (India) have conceded that poor demand management has significantly contributed to the development of this condition. “When the supply is more, consumption pattern changes causing overconsumption”, stated a Senior Project Officer, WRI India. Over the years, utilization of water resources has been steadily increasing for irrigation, domestic and industrial uses. No significant steps have been taken so far to rejuvenate the reservoirs, nor has there been planning based on future water needs. Professor and Officiating Director S Janakarajan from Madras Institute of Developmental Studies pointed out that Madras has had water crises in the past despite good monsoons. “Chennai does not have a long term strategy to deal with water crises. We solely depend upon two or three reservoirs and we think that we are well off to deal with the summer season” he complained.
Owing to the scarcity, CMWSSB has been able to supply only 650 MLD (million litres per day), against the city’s demand of 850 MLD. The fact that this number is likely to dwindle further into the summer is worrying water officials.
Conditions in the Institute
Before the crisis began, the institute was receiving a supply of 2 million litres a day from the metro, of which about 0.4 million litres were recycled for reuse. This is done by the Sewage Treatment plant set up near Research Park road. The institute also taps its lake reservoirs, providing us with about 0.3 million litres a day. Summing up, the institute had a potential pool of about 2.7 million litres a day – sufficient to cater to the campus’ daily needs.
As February inched closer and the city succumbed to its misfortune of inadequacy, the supply to our campus was drastically reduced by over 60%. The supply of water since has been rather irregular.
Water is currently being supplied to the institute by the metro in two rounds a day: 5 AM and 5 PM or 8 AM and 8 PM. However, water isn’t always received at the said times, and quite often, we don’t receive any water at all. We received an average of only 0.4 million litres from metro over the previous two weeks. Moreover, we received absolutely zero water from the metro during the second weekend of this month. About 0.3 MLD is being procured through lorries and about 0.2 to 0.3 MLD from the lakes. The Sewage Treatment Plant recycles about the same amount as before. This sums to about 1.3 MLD, which is only about 6.5% of the campus’ requirement.
“The water that is procured is supplied equally to all hostels”, says Nihal, the Hostel Affairs Secretary. “How long the water lasts in a hostel depends on how carefully the residents use it”, he added. Going by our calculation, each of the 20 hostels receives about 65 000 litres a day. The usage pattern of each residential zone differs and varies drastically over time. In emergency situations, some hostels have to be provided more water as compared to others. In general, hostels with more residents use up water faster than others.
“We always have 3 lorries of water ready, in case emergency situations arise”, said Nihal, when asked about measures that have been taken to address any emergency situations that may arise. It is at the hostel General Secretary’s discretion to take up the initiative and request for one of these lorries, in case the said hostel is in dire need of the resource. The contacts are available at every local hostel office.
In particular, Godavari and Sarayu were hard hit last weekend. Having spoken to Godavari’s hostel legislator, it was known that the hostel did not receive any water for the entirety of Saturday evening. The officials had to contact the Engineering unit for help, who provided the residents with a water tanker to temporarily satisfy their needs. Reportedly, not many tankers were available at the moment, which is why they were incapable of supplying through the overhead tanks to the taps.
Earlier this semester, the plumbing system of Godavari was under maintenance. The legislator informed the correspondent that one of the overhead tanks still isn’t working properly, and that the authorities have promised to get it fixed by Wednesday. Currently, the work is under progress. The hostel is still facing issues with availability of water, but not as much as it faced on Sunday.
While Godavari had an ill maintained tank, Sarayu’s pump gave up. The hostel General Secretary informed the correspondent that the hostel hadn’t been receiving water all through Sunday and for a short period on Monday. As the water level from where water was pumped into the tank reduced, the pump was unable to supply any water overhead. A tanker was requested for the residents who carried water for their needs in buckets. As of now, water is limited but the tank is opened up at peak hours.
Conditions in Chennai
The groundwater levels in Chennai have gone down by an average 1 to 1.5 meters since July last year. The average groundwater levels this year have been at about 7.6 meters below ground level, against 5.7 meters in December 2017. About 70% of the wells have gone dry this year, compared to only 25% in 2017.
Officials have observed alarming dips in groundwater levels across various locations in the city. Places like T Nagar, Triplicane, Choolaimedu and Maduravoyal have had more than a meter’s dip. At other places including Adyar, Ashok Nagar and Vadapalani, the reservoirs have become bone dry.
There are about 3600 water bodies in Kanchipuram, Chennai and Tiruvallur that are facing a deficit. Satellite imagery of the Chembarambakkam lake shows the reduction in its levels in 2017 and 2019.
Chennai administration is working towards identification of new quarries and lakes that will help reduce the blow of water scarcity in the upcoming months. Currently, a new quarry in Erumaiyur has been identified and pipelines are being laid from the same to Chembarambakkam to Water Treatment plants so as to maintain supply to the city. About 13 lakes have been surveyed around the city, of which 3 have been identified as potential reservoirs for tapping water this summer. Two desalination plants will be operated in the city to meet its demands. However, in the process of supplying water to the city, the desalination plants inflict substantial damage to the marine ecosystem, making them only a temporary measure.
Although the situation this year is worse than what was in 2016, officials assert that they are better prepared to handle the crisis than last time. “We will have more sources of water now than we had in 2017 because we will have water from Veeranam reservoir (fed by Mettur dam) due to resolution of the Cauvery water dispute and the water levels in Kandaleri reservoir (fed by river Krishna) is better than that in 2017″,said a senior official from CMWSSB. “Once the monsoon season is officially over, the restrictions placed on usage by CMWSSB will be back”, he added.
IITM’s Sewage Treatment Plant
While the city is reeling under the drought, our campus has an inspirational story to tell. In January 2017, our institute commissioned a state of the art 4 MLD (max capacity) sewage treatment plant (STP) armed with the latest Sequential Batch Reactor technology. The system was developed over a course of 3 years, with a costing of about INR 20 crore. This plant is capable of ameliorating raw sewage water to potable standards. A fully automatic Treated Water Distribution System is in place with 20 km long pipelines connected to every household, hostel and academic complex. The treated water conforms to Central Pollution Control Board (CPCB) norms and also has extra UV filtration and ozonation systems.
The government has given its nod to CMWSSB to replicate IITM’s successful model of ‘recycling and reusing’ sewage water to rejuvenate water bodies. The officials admitted that they are frantically looking for measures to rejuvenate the water bodies, considering the fact that they are only at 14% of their capacity. The sewage water will be treated in an STP similar that we have here and then will be discharged into lakes. They hope recharge groundwater and also create a sustainable source this way. Reportedly, the state administration has sanctioned a sum of INR 86 crore for this supply augmentation project.
Remedial Measures: What you can do
It is very likely that water supply will collapse further in the upcoming days. The institute will rely majorly on ‘grey water’, which is what recycled water from the sewage treatment plant is called. When asked whether it is a wise choice to stay in the campus during the upcoming summer, HAS deferred commenting. However, there are certain basic measures that the hostelers (or any other residents) should undertake in order to conserve as much water as possible.
- Reducing the usage of washing machines. They consume a lot of water, and therefore it is best to keep their usage minimal.
- Using buckets instead of shower heads while bathing. Studies show that a standard bucket bath consumes about 20 litres of water, while even special low flow shower heads(running at about 7 litres per minute) make even a short 5 minute souse a 35 litre affair. Further, people with bathtubs end up using no less than 150 litres per visit.
- Carrying water in a mug or bottle for brushing teeth or washing face. Even the small amount of water that flows away when we use a tap for this task matters.
- Any leakages in plumbing, whether in the hostel or outside, should be immediately reported to the General Secretary of the hostel who will then contact appropriate authorities to get the line rectified.
- Avoid using drinking water for sanitary purposes. Drinking water is as much a scarce resource as tap water.
- Keeping bathroom doors closed at all times. Monkeys are intelligent enough to open taps to drink but not to close them after they are done.
- Keeping taps in all bathrooms closed at all times. It is observed that in the absence of water supply, people turn on taps to check for water and then forget to turn them off. When the supply is reinstated, water keeps flowing leading to immense amount of wastage.