Goa's Mandovi River Faces Persistent Faecal Coliform Contamination Near Casino Zones
In a concerning environmental development, water samples collected from areas surrounding the casinos anchored in the Mandovi River have consistently shown elevated levels of faecal coliform, according to recent reports from the Goa State Pollution Control Board (GSPCB). Testing conducted at five key locations over several years reveals that the water has exceeded permissible limits for faecal coliform every month since 2022, with some periods recording levels up to 200% or higher than the allowed threshold.
Alarming Test Results and Statistical Analysis
The permissible limit for faecal coliform is set at 100 or less MPN per 100ml, where MPN stands for Most Probable Number—a statistical method used to estimate the concentration of viable microorganisms like E. coli in water samples. However, data tabled in the assembly indicates that, except for a couple of months, faecal coliform levels have remained 100 to 200% above this limit throughout the year, particularly during the 2024-25 period. For instance, in July and December 2024, readings soared to 2,300 MPN per 100ml, starkly contrasting the prescribed 100 MPN.
Underlying Causes and Pollution Classification
Reports attribute these high contamination levels to the ongoing impact of untreated or partially treated wastewater discharges into the Mandovi River. Despite findings of good oxygenation, stable pH, and low organic load in the water samples, the persistent faecal coliform presence highlights significant pollution issues. In a reply to the assembly, Chief Minister Pramod Sawant noted that the Central Pollution Control Board had initially classified a stretch of the Mandovi as a Priority IV river due to pollution in 2022. However, based on subsequent assessments, the river's status improved, leading to its removal from the polluted river classification in September 2025.
This reclassification was based on tests of 13 parameters, including copper, zinc, manganese, and iron, all of which were found within permissible limits. Yet, the faecal coliform levels remained alarmingly high, raising questions about the river's overall health despite meeting other criteria for declassification.
Casino Sewage Management and Regulatory Oversight
In response to the contamination concerns, the assembly reply detailed that all casinos operating in the Mandovi have onboard sewage collection tanks. These tanks are emptied under the supervision of GSPCB officials and the Captain of Ports, with the transferred sewage then sent for treatment at the PWD STP in Patto. A logbook is maintained by casino vessels to record sewage transfers, and this documentation is duly acknowledged by regulatory authorities to ensure compliance and monitoring.
The situation underscores the need for continued vigilance and enhanced measures to address water quality issues in Goa's iconic Mandovi River, balancing tourism activities with environmental protection.
