By Lucy Gibson
For Assam, the Bharalu, a small tributary of the Brahmaputra, is a big concern. The Bharalu flows through the heart of Guwahati city, through densely populated residential, industrial, and commercial areas. As a result, Bharalu carries a large proportion of the city’s municipal wastes, including sewage and wastage from markets, commercial establishments, hotels and restaurants.
The State Pollution Control Board has marked Bharalu as one of the most polluted river stretching the country with a BOD level of 52.0 mg/l making it completely unfit for drinking and bathing purposes.
Additionally, this polluted river leads into the state’s biggest wetland wildlife sanctuary, Deepor Beel.
Deepor Beel is located about 10km Southwest of Guwahati city. It is considered one of the largest and important riverine wetlands in the Brahmaputra Valley. Yet, as a result of unchecked urbanisation, it is fed by contaminated water and waste carried by Bharalu river, posing a significant threat to the biodiversity of the wetland, home to many aquatic species and migratory birds.
Deepor Beel has significant biological and environmental importance.
It is the only major storm-water storage basin for Guwahati city which regularly faces prolonged water-logging during every monsoon. It is also home to a rich variety of flora and fauna: with 50 indigenous fish species recorded and 212 species of bird, including kingfishers, fishing eagles, adjutant storks, and numerous varieties of ducks. Surveys have also revealed 20 amphibians, 18 snakes, 12 lizards, and 6 turtle and tortoise species make the beel their home.
Additionally, the Asian Elephant regularly visits the beel and the nearby forested areas are home to Assamese Macaque, Slow Loris, Leopards, and even Chinese Pangolin have been recorded according to BirdLife International.
In fact, due to its significant biodiversity, Deepor Beel is a designated Ramsar Site, and a designated Important Bird Area by Birdlife International.
This water body is also of great importance to its human residents, who located in the periphery and catchment use the Beel for: fishing, as a waterway, and to raise boro paddy. It also offers prospects for tourism if harnessed carefully without impacting its fragile ecology. With the dense Garbhanga hills proving a stunning backdrop, and the wetland being widely known for being home to many species of flora and fauna and is a popular attraction for photographers.
However, Deepor Beel is bearing the brunt of unplanned development.
The proliferation of human settlements, roads, and industries around the periphery are adding to pollution problems. Hunting, trapping, and intensive fishing practices are resulted in the death of wild birds and mammals.
A railway track also runs through the water body, near its south bank. Plans for a second railway track pass directly through a part of the Beel which is used by elephants as a major corridor.
The Guwahati oil refinery waste is directed through the Bharalu and Kalmoni rivers to the beel. The channels also carry other industrial and hospital waste. Continued discharge of the city’s untreated sewerage through the Bahini and Bharalu rivers and the dumping of municipal solid wastes in its close proximity by the Guwahati Municipal Corporation (GMC) have pushed the wetland’s pollution to alarming levels and caused a fall in oxygen levels resulting in the death of fish and aquatic life. Previously fishing was enough to sustain some local communities, but now the situation has changed.
Invasive weeds such as water hyacinth, too, are expanding to more and more areas. These problems worsen during the monsoons, with rainwater sweeping large amounts of rubbish from the dumping site to the Beel.
Guwahati generates about 450 tonnes of waste every day, rubbish that finds its way to the periphery of the beel. This rubbish dump is home to one of the largest concentrations of greater adjutant stork.
On January 22, 2017, 22 Greater Adjutant storks were found dead in Deepor Beel. Many suspect that it was because the birds eat the rubbish at the site. Greater Adjutant storks find themselves ‘endangered’ on the IUCN Red List of Threatened Species and population numbers are decreasing,
Wetlands act as some of the best indicators for a city’s environmental status.
Quite simply, fewer birds visiting the wetland would testify to the increasing pollution of the city and the effects of this on the environment.
While the management authority for Deepor Beel is the Forest Department of the Government of Assam, several public and private institutions and universities are involved in creating awareness of the ecological importance of the beel and the need to restore it to its original status.
Deepor Beel plays a significant hydrological, biological, and ecological role, as well as holds substantial socio-economic and cultural value. Put simply, there is a lot to lose.