If all goes as planned, Gujarat over the next decade will have an extensive network of deep-sea pipelines to discharge effluents from its seven industrial clusters—Ahmedabad, Vadodara, Ankleshwar, Surat, Vapi, Sarigam and Jetpur—into the Arabian Sea. Aiming to save the Sabarmati and other critically polluted rivers of the state, the Gujarat government informed the Vidhan Sabha in September that seven such deep-sea pipelines, also known as marine outfalls, are in various stages of planning and execution. The state’s first such major pipeline was made operational in 2016 in Bharuch district—from Jhagadia industrial estate to the coastal village of Kantiyajal about 60 km away—which disperses treated effluents into the Gulf of Khambhat at a depth of 11 metres, 9.4 km from the shore.
While the Rs 8,000 crore-plus project is expected to give rivers flowing through the state a new lease of life, environmentalists have raised concern over its possible impact on marine ecosystems and coastal habitations. Industries in Gujarat produce 575 million litres per day (MLD) of effluents. Of this, 60 MLD, or 11 per cent, is discharged directly into the sea, and the remaining 515 MLD, or 89 per cent, is let into various rivers and creeks.
The Central Pollution Control Board (CPCB) in 2018 identified 20 polluted river stretches in Gujarat, of which five—Sabarmati, Bhadar, Bhogavo, Amlakhadi and Vishwamitri—are classified as ‘critically polluted’. The pollution in the Sabarmati in Ahmedabad and Mahi near Vadodara has, in particular, become unbearable due to its detrimental impact on aquatic life and the lingering stench. Untreated and illegal discharge of industrial wastewater and domestic sewage into these non-perennial rivers has been identified as the root cause.
The Need For Outfalls
According to the Comprehensive Environment Pollution Index (CEPI), the industrial clusters of Vatva and Narol in Ahmedabad, Ankleshwar in central Gujarat and Vapi in south Gujarat have been among the ‘critically polluted areas’ since 2018—leading to a CPCB moratorium on any expansion in these clusters. Looking for a solution at the time, representatives of multiple industrial estates had urged the government to construct a network of marine outfalls in the state. This is because the norms for effluent discharge into the deep sea are relaxed in comparison to those for rivers, thus reducing the cost of treatment.
Take, for instance, the permissible limit for biochemical oxygen demand (BOD) and chemical oxygen demand (COD)—both used to determine the amount of organic pollution in liquid waste. While the CPCB mandates a maximum BOD of 30 milligrams per litre and COD of 250 mg per litre in the case of treated effluents being discharged into rivers, the norms have been relaxed to 100 mg and 500 mg, respectively, when it comes to deep-sea discharge. Why such relaxation? Because marine outfalls rely on the assimilative capacity of the sea to further dilute any detrimental effects of industrial waste.
“By implementing deep-sea disposal solutions and providing appropriate deep-sea lines, it is possible to remove the tag of critically polluted areas from these clusters,” noted a Gujarat Chamber of Commerce and Industry (GCCI) report while making a case for marine outfalls. This will “allow for [industrial] expansion in these regions and create direct and indirect employment opportunitiesâ€ægenerating revenue for the government,” it added. The proposal, though approved by the industries department, was rejected by the water resources department. The reason being that the outfalls were proposed at the site where the Gujarat government plans to undertake its ambitious Kalpasar project—a freshwater reservoir envisaged for tidal power generation, drinking and irrigation purposes—by building a 30-km-long dam across the Gulf of Khambhat. (First proposed in 1988, the project is still undergoing feasibility studies.)
The grand plan
So, while the marine outfall proposal hit a roadblock, the Gujarat High Court had been repeatedly taking the state government to task over the past few years for its inability to clean the Sabarmati. In June this year, the government was directed to submit a concrete time-bound action plan in this regard. A month later, the water resources department finally gave its nod to the deep-sea effluent discharge project, but only after the total length of the pipeline originating in Ahmedabad was extended from 130 km to 210 km to take its outfall point beyond the proposed Kalpasar lake. Following this, the other six pipelines have also received an in-principle approval. The Gujarat Water Infrastructure Limited and Gujarat Pollution Control Board (GPCB) are the executing agencies.
The total cost of construction is pegged at Rs 8,321 crore, of which the participating industries will bear 20-30 per cent. The pipelines are expected to become operational over the next 10 years, though their offshore length and depth are still being worked out. In the case of the Ahmedabad pipeline, which will cost about Rs 1,500 crore, 3,050 units from 11 industrial areas have joined the project. “Meeting the norms set for effluent discharge into rivers is financially unviable for the industry,” says former GCCI chairman Shailesh Patwari, while emphasising the project’s importance. “These norms are very strict globally as river water percolates into aquifers, and is used for irrigation and drinking. Moreover, not being perennial, the Sabarmati and other rivers fail to dilute the industrial discharge.” So, the industries in Gujarat, he adds, are left with two options: deep-sea discharge or zero liquid discharge. The latter process, wherein all water is recovered and contaminants reduced to solids, “is not financially viable for small- and medium-scale industries”, says Patwari. “So, deep-sea discharge is the only solution.”
A Cause Of Concern
The world’s first marine outfall, built in Santa Monica, United States, dates back to 1910. The largest, in Boston, discharges sewage after extensive treatment. Over 100 marine outfalls dot India’s 7,516-km coastline as well, but several reports have raised concern over the bulk of wastewater being disposed of without being treated properly, putting marine ecosystems at potential risk.
Despite the sea’s assimilation abilities, chemical-infested effluents are known to reduce the oxygen content in water, impacting marine life. Studies conducted by the Chennai-based National Centre for Coastal Research (NCCR), which works with state pollution control boards to monitor the effluent discharge at about 50 locations in India, have shown that the fish stock has taken a beating due to marine pollution, impacting the fishing industry over the course of time. “The Indian coastal waters do not face serious concern yet,” maintains NCCR director Dr M.V. Ramana Murthy. “If the norms are followed, we should be able to maintain the ecological balance.”
Eventually, it all boils down to the effective working of common effluent treatment plants (CETPs), set up to help small- and medium-scale enterprises—which are unable to afford the installation of pollution-control equipment—dispose of the effluents safely and economically. But in the case of deep-sea discharge, monitoring becomes all the more difficult as it may take time for the impact of dilution to become apparent.
“Dilution is not the solution,” says environmental activist Rohit Prajapati. A member of the joint task force formed by the Gujarat High Court to deal with pollution in the Sabarmati, Prajapati suggests that if the cost of treating certain chemicals is financially unsustainable for businesses, then “the solution is to phase out such chemicals, not dump them untreated into the sea”.
Poor functioning and monitoring of CETPs and flouting of effluent treatment norms by industries are the precise reasons that the rivers in Gujarat are severely polluted. A 27-km-long pipeline, which discharged treated effluents from three industrial clusters around Ahmedabad into the Sabarmati, had to be shut down earlier this year, says a reliable source privy to the development, after the detection of 167 illegal connections. How a 210-km pipeline passing through multiple industrial estates and villages will be monitored is anyone’s guess.
According to a veteran scientist, who prefers to remain anonymous, regulators decide the effluent discharge norms based on the existing pollution load of a water body, be it a river or a sea. “We do not have a detailed study regarding the carrying capacity of the Arabian Sea, particularly the Gulf of Khambhat,” he notes. “Then on what basis have the discharge norms been decided?” In its written reply in the state assembly on September 15, in fact, the Gujarat government had admitted that the environmental impact assessment is not needed to lay a deep-sea discharge pipeline.
Key Lessons
Prajapati says that a 2021 high court order had noted that the tidal activity in the Gulf of Khambhat “drives the highly toxic and polluted wastewater inland, to the estuaries of the Mahisagar and Sabarmati rivers, causing tremendous risk to the settlements, villages and towns in the region”. The functioning of the existing marine outfall does not inspire any confidence either. A report by the Narmada Pradushan Nivaran Samiti, a non-governmental organisation, in 2020—four years after the Jhagadia pipeline was made operational—alleged that the effluents did not meet the norms at the point of discharge from the CETP. Even as a committee appointed by the National Green Tribunal concluded that, barring a few exceptions, the treated effluents were within permissible limits, it conceded another finding of the NGO—there were over two dozen leakages in the pipeline, due to which the hazardous waste was seeping into farmlands.
According to a senior GPCB official, who talked to india today on the condition of anonymity, the working of the new CETPs will be monitored every fortnight, though checking the entire pipeline will still not be possible. “Agencies like the National Institute of Oceanography and the Council of Scientific and Industrial Research typically measure the impact [of outfalls] on marine life and ecology every two to three years,” he adds. “The Jhagadia pipeline hasn’t been found to damage the marine ecology.” Given that such claims have been contested time and again, it is imperative that the Gujarat government addresses all concerns promptly if it wants the project to be a success, from both environmental and economic perspectives.