Routing massive amounts of stormwater into beaches through pipes can have significant environmental, ecological, and health:

• Beach erosion: Discharging large volumes of stormwater into beaches can accelerate coastal erosion. The force of stormwater flow can strip sand from the beach, destabilize dunes, and weaken natural coastal defences. Sediments from SWDs can alter natural sand movement patterns.
• Pollution of coastal waters: SWDs in Chennai have often been reported to also carry sewage. Such water when routed directly to the beach introduces these pollutants into the coastal ecosystem, directly impacting marine life.
• Marine ecosystem disruption: Sudden influxes of fresh water can disturb the salinity levels of coastal waters, impacting marine species adapted to specific saline conditions. Pollutants carried by the stormwater can also cause toxic algal blooms, harm fish populations, and disrupt the broader ecosystem. An example of this was the bio-luminance spotted across Chennai beaches.
• Backflow during high tide: During high tide, there will be a backflow of waterflooding in low-lying areas or streets near the coast, as the pipes intended to carry water away from these areas are instead carrying seawater back into them. It will also increase the pressure on the drainage system and accelerate erosion of pipes due to saltwater, thus increasing maintenance costs. 
• Impact on tourism: Polluted stormwater discharges can make beaches unsafe for recreational activities such as swimming, surfing, and fishing, negatively impacting local tourism and the economy.

Such discharge can be seen not at one but two places on Thiruvanmiyur beach and multiple places all along the Chennai coast. At Palavakkam and Kottivakkam, sewage is let out at the beach through pipes.

The beaches from Marina to Uthandi come under CRZ 1A and 1B. As per the Ministry of Environment and Forest, “No new construction shall be permitted within 500 metres of the High Tide Line. No construction activity, except facilities for carrying treated effluents and wastewater discharges into the sea, facilities for carrying seawater for cooling purposes, oil, gas and similar pipelines, will be permitted between the Low Tide Line and the High Tide Line.” Any other construction is a violation.

This practice underscores the need for a sustainable and environmentally sound flood mitigation strategy that takes into account the fragile coastal ecosystem and the well-being of local communities.

What would it take for the GCC to take notice and take corrective action immediately?

Efforts to Resolve the Issue

In 2022, Councillor J.Kayalvizhi tried to address the situation and cleared a part of the obstruction on L.B.Road (Adyar Times dated 30 Oct 2022). The residents also took their grievances to the National Green Tribunal (NGT), requesting that their stormwater drains (SWD) be connected to L.B. Road (near Hot Chips) to prevent flooding. This plea led to various government departments being asked by the tribunal to respond to the delay in providing relief to the residents.

Greater Chennai Corporation (GCC) officials initially agreed to study the SWD issues and promised to design a more efficient drainage system. However, they and other departments (CMWSSB, BSNL, etc.) pointed fingers at each other for the delays, leaving the residents frustrated and with no clear solution in sight (Adyar Times dated 15 Oct.2023).

Continuing Flooding

Despite assurances from the GCC, Kamaraj Nagar’s residents continue to face the same challenges during this year’s monsoon. On Oct.17, the East Kamaraj Nagar (North) Residents Welfare Association filed an interim application with the NGT, highlighting the GCC’s failure to resolve the flooding issues. They highlighted that GCC’s stormwater management plan has been inadequate, particularly during heavy rains in mid-October.

The GCC had previously claimed that the majority of the work to fix the drainage issues had been completed, with only 5% of the project left. However, residents reported that the key component of the solution – a well designed to store stormwater and pump it into the Buckingham Canal, had failed to perform as expected. The well, about 20 feet deep, was unable to hold sufficient water, and the pump installed was not powerful enough to extract water (3 feet of water coming in and 1 inch of water pumped out), thus leading to flooded homes.

Sewage water complicates the problem

Even before the construction of the well was over, residents reported that sewage had started flowing into it. Despite informing the local councillor and the GCC, the issue remained unresolved. Thus to draw attention to the issue, residents staged a protest on Oct.12, demanding that the GCC take immediate action to complete the project before the monsoons intensified.

se rapidly, overwhelming the GCC’s pumps. The rainwater entered homes on the 2nd and 3rd East Streets, highlighting the inadequacy of the well design and the pump’s capacity. Additionally, the stormwater was not being discharged directly into the drains, but instead into chambers, which created reverse pressure and worsened the flooding.

Calls for permanent solutions

Residents pointed out that stormwater from Kamaraj Nagar is supposed to be discharged into the SWD at L.B. Road, but this has not happened due to obstructions, including BSNL cables blocking the drains and sewage discharge preventing proper flow. Furthermore, rainwater from L.B. Road itself has added to the flooding problems. Residents have called for the final discharge point of stormwater to be moved to the southern side of Thiruvalluvar Salai and for the Buckingham Canal to be desilted to ensure it can handle the increased water flow.

In their application to the NGT, the residents requested the tribunal to direct the GCC to redesign and implement an efficient SWD system that ensures seamless connectivity to the Buckingham Canal. They hope that with proper planning and execution, they can finally experience a flood-free monsoon in the next season.

The ZO sought the cooperation of the RWAs and volunteers to help steer through the upcoming monsoon with the following suggestions:

• Educate all residents about safety measures and flood preparedness, e.g., essential provisions to be stocked etc.
• Collaborating with local authorities to monitor drainage systems and water levels. 
• Assisting the elderly and differently-abled, during emergencies. The residents were requested to maintain a database of the elderly, differently-abled and pregnant women in their locality and be in touch with them for any help.
• Organising clean-up drives to prevent blockages in water channels. The ZO informed that despite multiple cleanups in water channels, poor civic sense among the public was leading to frequent choking of drains.

The residents also took this occasion to present their issues and questioned about practices in place/lessons learnt from last year’s monsoon. The highlighted issues include:

• SWD issues: No desilting of existing stormwater drains (SWDs), choked catchment pit with tar and mud, catchment pit sealed during road laying, improper slope leading to the drain, no check on sewage being let out into SWDs, disconnected SWDs (especially at Kamaraj Nagar East and Journalist Colony) and insufficient depth of SWD (Kannapa Nagar).
• Sewage issues: Most of the neighbourhood complained of sewage backflow inside residences during monsoon, especially when the roads were flooded. Also overflowing sewage on the roads. The Councillor also informed that they are upgrading pumping stations to tackle the issue.
• EB issues: After the construction of SWDs, the EB lines are out in the open and pose an enhanced risk during monsoon due to: (a) can cause tripping, (b) make pavements not fit for walking, (c) one hopes that the EB wires are well insulated.
• CMRL issues: The residents of 2nd Avenue Indira Nagar pointed out that due to CMRL work, the existing SWD has been rendered useless and the alternative SWD constructed has not been connected with the main pipe. The ZO informed that he would look into it. During the rains of Sep.25, the residents informed that the roads were totally flooded and the water was inches from entering homes. Despite informing the Corporation, help came in late and water did not recede till the wee hours of Sep.26.
• Flooding: Residents pointed out rampant concretisation as the main culprit of flooding, with no place for the water to seep in. Residents of Rukmini Road (Kalakshetra Colony) looked forward to a flood-free monsoon. The Councillor informed that diesel pumps are being readied and will be deployed at the slightest flooding. Residents of Dr.Radhakrishna Main Road and Kalakshetra Road (Thiruvanmiyur) pointed out that flooding prolonged in their areas due to pumping out of water by residences with basements. they suggested that the pumped water must not be let out on the road, but must be collected in tankers and discharged into water bodies. Residents of Karpagam Gardens thanked the GCC for relaying a bigger capacity SWD and for coordinating with Shiv Nadar School and Theosophical to ensure smooth water flow.
• Pruning of trees: The Councillor stated that the GCC had allotted the pruning machine for 3 days each for each ward, however, she has requested it for a longer time as areas like Kalakshetra Colony have more greenery.
• Encroachments: Residents pointed out encroachments on pavements have rendered pavements unfit for walking and this issue is aggravated during monsoon due to the flooding of roads.
• Other issues: Proper desilting of the Buckingham Canal end to end and its maintenance for proper flood mitigation. A check on rainwater harvesting systems in residences as well as commercial establishments to ensure no run-offs and recharge of groundwater. Relaying of all left-out roads with proper slope to prevent waterlogging. Residents also requested the GCC to obtain a GO to clean vacant plot (including private) to ensure their cleanliness, tackle waterlogging and prevent anti-social elements (especially in Velachery areas). They also pointed out that snakes are often seen during monsoon, which bite other animals. They asked for measures to be taken for the voiceless as well. Velachery residents also sought a check on encroachments around water bodies and canals, and ensure that channels were clear and big enough to take the load of water. They also requested the Corporation to prepare for the worst scenario and stock relief places with food and water so that residents don’t need to depend of air-drop of food packets.

The ZO concluded by stating that pumps will be deployed in advance at all places that are prone to flooding and enhanced anti-flooding measures will be deployed from next year onwards. Residents also pointed out that the presence of other stakeholders like TNEB, CMWSSB etc. was essential for constructive discussions in such meetings.

Below are the highlights from the meeting:

At the meeting, the Corporation AE said that nothing could be done for the current rains, however, a permanent solution will be planned after ECR widening and the stormwater drain construction is complete, post which the line from Valmiki Street shall be joined to ECR. 

As a temporary measure, a sump / well with a submersible pump is being planned near the Adyar Bakery junction. Also, they will get approval for fixing a suitable pipe from the lowest point of Valmiki Street to ECR and the same will be implemented within a month. 

AE CMWSSB informed that a new plan has been prepared for relaying new pipelines and installing a pumping station opposite Shruthi Apartments, for 

which the Corporation needs to provide the necessary space for wells and pumps.

Meanwhile, the residents suggested the below temporary measures:

• Establish a pipeline connection from Cholapuram Street to the SWD in Valmiki Street so that rainwater flows to the drains of Kalakshetra Road or ECR as appropriate.
• Desilting and cleaning of the recharge wells and SWDs in Cholapuram and Valmiki Street.
• GCC could evaluate the possibility of constructing drain pits (at the discarded gym), to pump the stormwater (similar to the one at the Jayanthi Signal). This is in case Valmiki Street water cannot naturally run through to Kalakshetra Road, due to terrain issues.

In response to an affidavit filed by the East Kamaraj Nagar Residents Welfare Association with the National Green Tribunal, on the sewage and flooding issues of the locality, the Tribunal has asked the Greater Chennai Corporation (GCC) to file a report on the issue status by Nov.30.

The GCC told the Tribunal that they, in coordination with the other departments including the Highways Department, were planning on a permanent solution for the problem raised by the RWA, and requested 6-8 months of time to complete the coordination with other departments. The Tribunal asked the GCC to file a status report, with details on action taken, project report, funds sanctioned and timeline for completing the work.

The RWA, in their case, had requested to:

• Connect the stormwater drains (SWD) of Radhakrishnan Nagar directly to Buckingham Canal without entering East Kamaraj Nagar; Ensure that the SWDs in East Kamaraj Nagar (North) are connected to the Buckingham Canal to prevent flooding in East Kamaraj Nagar during monsoons.
• Fix sewage leak into SWD.
• Remove the dead BSNL cables inside SWDs, to allow free flow of water
• Rectify the gradient of SWD.

Following this, the Tribunal sought responses from Tamilnadu Pollution Control Board (TNPCB), GCC and Chennai Metro Water Supply and Sewerage Board (CMWSSB).

The GCC replied that:

• There is no SWD connectivity from Radhakrishnan Nagar to East Kamaraj Nagar (North). The flooding was because the locality is a low-lying area (almost 2-3 ft below Kalakshetra Main Road and Thiruvalluvar Salai of ECR), and thus all run-off gets accumulated there, necessitating pumping out of water, despite SWD.
• The old SWD at the Thiruvanmiyur LB Road signal was in a dilapidated state, thus hampering free flow of water. However, GCC resolved the issues of telecom cables and high tension wires and relaid the SWD. GCC has also agreed to study the functioning of the SWD network in West Kamaraj Nagar area and evolve suitable designs.

The CMWSSB stated that:

• The sewage outfalls have been plugged and the existing sewage system is adequate to ensure no overflow of sewage into SWDs.
• The mixing of sewage occurred in the months of Oct – Dec, 2021, due to unprecedented rains, when rainwater entered into the sewage system, leading to backflow of sewage. However, the same was resolved by CMWSSB and no issue of mixing was reported since.
• Some of the illegal sewer connections were plugged on being notified. GCC has been informed that some of the commercial establishments on L.B.Road were letting out sewage into SWD illegally, despite having a sewer connection. 
• Three of the machine holes, which were in dilapidated conditions, were fixed.
• Despite BSNL cables running through the SWD, it is frequently desilted to ensure free flow.

The TNPCB observed:

• Crisscrossing BSNL cables would hamper flow of water in case floatable solid waste got stuck over the cables. BSNL claims that the laid cables pre-date the SWD and thus the responsibility of the proper construction of SWD lies with the GCC, but the cables have to be rerouted after construction of SWD.
• SWD at Kamaraj Nagar was found to be at a lower level with respect to the L.B.Road – ECR, necessitating pumping out of water. GCC, however, must maintain gradients based on the topography of the region and the study conducted for the same. A new study to verify the gradient and take corrective measures was also suggested.
• Though no sewage water was found in the SWDs, CMWSSB has been instructed to ensure flow of sewage to treatment plants.