Vaigai needs a thorough cleaning from the hills to the sea

197 pipes or canals bring sewage into Vaigai at 177 spots from Valipparai in the hills to Attrankarai in Ramanathapuram district where the river joins the sea, say experts

Trickling down the Varushanad hills near Valipparai village in Theni district, Vaigai river begins to take shape. Here, the water rippling over smooth pebbles on the riverbed is crystal clear. Fit for drinking, say the villagers and the team from Madurai Nature Cultural Foundation (MNCF), who were on a survey mission, drank the cool and sweet water before a sample was taken for testing.

Within 24 hours, the test was done at Water Quality Testing Laboratory, Water Watch Centre, The DHAN Academy, Madurai, and the result was shocking. As per the Central Pollution Control Board, water quality has been classified into A, B, C, D, and E category. The water taken from Valipparai was of D grade, which means it is fit only for wildlife and fisheries. This came as a shock for the MNCF people who were on a six-day continuous study from August 28 to September 2, right after the end of south west monsoon season when there was water flow in the river.

Apart from chemical fertilizers being used in the coffee plantation in the region, another major factor for contamination were the villagers themselves. Valipparai has conservancy workers, but no place to dispose of the waste. The garbage collected is heaped near the river and with no Under Ground Drainage (UGD) scheme, sewage is let into the river. This place is home to smooth coated otter, which as per the International Union for Conservation of Nature (IUCN) is a vulnerable species. But as pollution level rises, will the otter still call this place home, is a question.

The Vaigai river basin covers an area of 7,009.13 sq km. It originates from Varushanadu valley and flows northwards through Kandamanayakkanur. Numerous tributaries like Theniyar that joins Suruliyar joins the Vaigai near Kottaipatti. Thereafter, Vaigai flows east and then takes the south east direction till it joins Bay of Bengal. Varattar, Nagalar, Varahanadhi, Manjalar, Marudhanadhi, Sirumaliar and Sathayar that originate in Palani hills are the main tributaries that join Vaigai along its course. Uppar river originates in the Alagar hills and joins Vaigai near Manamadurai. The length of Vaigai river up to Ramanathapuram big tank is 266.71 km and from Ramanathapuram big tank to the sea it is 28.40 km. The total length of the river from its origin to sea is about 295.11 km.

As pointed out by an expert from Dhan Foundation, the river is seasonal. The flowing period can be said to be about four months in a year and this too depends on climatic conditions and rainfall in the catchment areas. After Vaigai dam was built and the parallel Periyar canal was established, the flow of water has been diverted to the canal thus resulting in less flow in the river. This creates a unique problem, especially when one takes into account the pollution level in the river as sewage stagnation is more during most of the months when there is nil flow.

The river course has urban settlements like Madurai, Cumbum, Uthamapalayam, Bodinayakkanur, Theni, Periyakulam, Manamadurai, Paramakudi and Ramanathapuram and also a large number of rural settlements that are highly populated.

Some of the settlements have no Sewage Treatment Plants (STPs) and some like Madurai that have STPs do not function to its full capacity. Fingers are pointed at unfinished UGDs in almost all these areas that have led to untreated sewage being let into the river. The MNCF team has identified 197 pipes or canals bringing sewage into Vaigai at 177 spots from Valipparai village to Attrankarai  in Ramanathapuram district where Vaigai joins the sea. As a result, out of the 36 samples collected by MNCF - 31 were collected in Vaigai river, 1 each in Suruliyar, Manjalar and Varahanadhi - nearly five samples from Vaigai river were below E grade and those collected from Suruli, Varahanadhi and Manjalar were D grade.

Tamildasan of MNCF says that what is imperative is not smart cities but smart villages. “By cleaning Vaigai along Madurai alone we cannot achieve complete success as protection of the river should start from the source,” he says and adds that waste and sewage management not just in cities but also in villages should be the moot point. 

There are no major polluting industrial units near Vaigai and the only major pollutants are household waste and sewage. Setting up STPs for urban areas is surely a costly affair that may run to few crores, but STPs in villages with less population can be done within few lakhs, says S. Praveen Kumar, a Dhan faculty member. Use of simple technology can bring about a significant change in water quality, he says.

The river, though seasonal, has not just an utilitarian connection with the people living on its banks but it also has an emotional and cultural tie. In ancient Tamil literature, Vaigai has been mentioned as ‘vaiyai’ and it has been mentioned more than 80 times in Sangam literature. The oldest inscription discovered in 1961 tells of Senthan Maran, a Pandya king, of 6th century BCE, building a sluice across Vaigai. The oldest ‘seppedu’ (copper plate grant) mentioning the river is from the period of Viswantha Nayakkar (1529-64 CE) that tells of grants given to Telugu speaking people in the region of Suruli Nadhi and Vaigai. There are 16 places along the river where people celebrate Alagar’s entry into the waterbody during the Chithirai festival.

It is this cultural connection that can be used to leverage people’s participation in conservation of the river, say conservationists. A river cannot be studied in isolation, the riverine ecosystem is of paramount importance. A healthy biosphere will keep the river healthy, says N. Karthikeyan of MNCF. Ancient literature points to numerous trees lining the riverfront, but with concretisation of the riverbanks the trees have all been cut and the green cover has been lost. “We recorded 80 ancient temples located about 1 km from the bank of the river but Thala Maram or sacred trees associated with these temples have all been lost. Trees act as a natural filter of pollutants, reduce soil erosion, and they not just regulate flow of water but also increase groundwater level and provide habitats for wildlife and fish,” he adds.

At Attrankarai  village, where the backwaters should have had a thriving mangrove, what remains are very scant flora associated with mangroves. The MNCF team noted an unrestrained growth of Prosopis juliflora throughout the course and with water hyacinth (Eichhornia crassipes) flourishing in many spots indicating the presence of sewage.

The wetland bird distribution also establishes the health of the river as they are responsive to environmental changes.

As the amount of sand in the river has decreased with increase in accumulation of mud and waste, the number of fish has also decreased. This has resulted in sightings of low numbers of piscivorous bird species like Kingfishers, terns and egrets while those eating worms and snails like open-billed storks, ibis and water fowl were found in large numbers.

With the health of Vaigai being important for sustainable development of the cities and towns that depend on it, experts feel that it is time town planners thought out of the box. Villages near the river course should become a focal point of nascent rural planning and performance evaluation of STPs in urban areas should be strictly enforced. The State government should have a strict river policy so that all stakeholders are answerable for their actions, they say.

Published - November 24, 2024 06:56 pm IST