Lessons from Bellandur: Governments should allocate more resources to monitor, and protect lakes

Subject: Environment

Section: Places in news

Context:

Bengaluru’s Bellandur Lake has been in the news for the last few years owing to the mysterious foam formation in the lake. Attempts made over the years to solve the issue were unsuccessful, as the issue occurs almost every year, especially after heavy rains.

Bellandur Lake pollution:

Bellandur is one of the many lakes in India facing the impacts of improper wetland conservation as well as waste management.
In addition to biodiversity loss, encroachments are among the major issues.

Study findings:

A recent study by the Indian Institute of Science identified the reasons for the foaming.
The study pitched surfactants in the sewage (residues of washing powders and shampoos) as the main culprit.
Overall, 53 per cent of the world’s largest lakes have been losing water, and 24 per cent have seen an increase. Nearly 33 per cent of the global population resides in a basin with a large, drying lake.
Because the Bellandur Lake is large, the sewage takes 10-15 days to disperse through the lake; during this time, a part of the organic material gets degraded in the absence of oxygen and settles down as sludge.
Surfactants in the sewage do not disintegrate when more and more sewage runs through the lake; instead, they get loosely attached to the settled sludge and progressively increase in concentration, sometimes reaching up to 200 times the initial concentration.
Heavy rains and certain foam-causing bacteria also worsen the situation.

Water and wetland exploitation:

Water usage has increased 600 per cent over the past 100 years, and one-third of wetlands have been lost over the last 50 years.
Since 1900, 64 to 71 per cent of wetlands have been lost.
Of these, Asia has a high rate of wetland loss due to large-scale coastal and inland natural wetland conversion.
A lot of the lakes in India are also lost or have been altered owing to human interference.
- Shrinking of Chilika Lake in Odisha to 915 square kilometres (sqkm) from 2200 sqkm and Dal Lake in Jammu and Kashmir, which has now reduced to an area of 12 sqkm area which is less than half its usual size.

Need for sustainable lake management:

In March 2022, United Nations Environment Assembly adopted a resolution on sustainable lake management — the first-ever resolution dedicated primarily to lakes.
- It requested the member states to protect, conserve, restore and ensure sustainable use of lakes.
- The resolution intended to accelerate actions and set the agenda for future actions being pursued towards lake conservation along with Sustainable development goals on water and Ramsar Convention on Wetlands.
UN General Assembly has also announced a decade of ecosystem restoration (from 2021 to 2030).
- The decadal mission was prompted by a proposal initiated by 70 countries across the globe, led by UN Environment Programme (UNEP) and the Food and Agriculture Organization.
- It aims to ramp up political interventions and on-ground initiatives towards the restoration of billions of hectares of terrestrial and aquatic ecosystems.
Ecuador, the Democratic Republic of Congo, Colombia, Gabon, Mexico and Zambia have launched a freshwater challenge at the 2023 UN Water Conference held in New York.