Wednesday, 15 May 2019

UNEP report on Sand and Sustainability

ontext: The UNEP has released a report, “Sand and Sustainability: Finding new solutions for environmental governance of global sand resources.”
Problem is highlighted in the report:
  • Sand consumption globally has been increasing and we are extracting it at rates exceeding natural replenishment rates.
  • Sand and gravel are the second largest natural resources extracted and traded by volume after water, but among the least regulated.
  • While 85% to 90% of global sand demand is met from quarries, and sand and gravel pits, the 10% to 15% extracted from rivers and sea shores is a severe concern due the environmental and social impacts.
  • A 40-50 billion tonne of crushed rock, sand and gravel is extracted from quarries, pits, rivers, coastlines and the marine environment each year. The construction industry consumes over half of this, and will consume even more in the future.
  • China and India head the list of critical hotspots for sand extraction impacts in rivers, lakes and on coastlines.
Cause for concern:
  • Their extraction often results in river and coastal erosion and threats to freshwater and marine fisheries and aquatic ecosystems, instability of river banks leading to increased flooding, and lowering of ground water levels.
  • Most large rivers of the world have lost between half and 95% of their natural sand and gravel delivery to ocean the report says.
  • The damming of rivers for hydro-electricity production or irrigation is reducing the amount of sediment flowing downstream.
  • This broken replenishment system exacerbates pressures on beaches already threatened by sea level rise and intensity of storm-waves induced by climate change, as well as coastal developments.
  • There are also indirect consequences, like loss of local livelihoods — an ironic example is that construction in tourist destinations can lead to depletion of natural sand in the area, thereby making those very places unattractive — and safety risks for workers where the industry is not regulated.

What needs to be done?
  • Better spatial planning and reducing unnecessary construction — including speculative projects or those being done mainly for prestige — thereby making more efficient use of aggregates.
  • Investing in infrastructure maintenance and retrofitting rather than the demolish and rebuild cycle, embracing alternative design and construction methods, even avoiding use of cement and concrete where possible, and using green infrastructure.
  • Need for large-scale multipronged actions from global to local levels, involving public, private and civil society organisations. This will mean building consensus, defining what success would look like, and reconciling policies and standards with sand availability, development imperatives and standards and enforcement realities.

Sources: The Hindu.

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