Healthy and free-flowing rivers are essential to meet the SDGs

This month two global news about rivers attracted my attention.  One, the Colorado River, for dying a slow death due to climate change; and two, 25 Cuban rivers for showing signs of good health due to years of sustainable farming. 

At a time when the world is facing unprecedented water crisis and is almost in a climate emergency, saving our rivers is of utmost importance.  While the news of despair, of the Colorado River, represents the state of most of our rivers; the news of hope, of the Cuban rivers, is one among the few such good news we come across. 

We are dependent on the rivers for our freshwater supply, be it for drinking, sanitation, domestic, irrigation and several other needs.  Besides these there are several ecosystem services the rivers provide and without which it is almost impossible to meet the Sustainable Development Goals (SDGs). About 844 million people in the world still lack even a basic water service.  While that’s a huge challenge and a difficult task to be met by 2030 especially because the freshwater crisis in the world is growing by the day, another bigger challenge is also to progressively improving the quality of services to 2.1 billion people who lack water accessible on premises, available when needed and free from contamination (safely managed drinking water). The world is also tasked with going beyond household connections and providing access to quality water and sanitation services in schools, health-care facilities and other institutional settings.  2.3 billion people still lacked basic sanitation services. Stressed rivers would not only reduce the chance of meeting the SDG targets but also increase the service gaps between the haves and have nots in a world where income inequality is growing at a highly worrying rate.

Colorado, the face of our stressed rivers

Coming to the Colorado River, a latest study has found out that a regional temperature increase of 1.4 degrees Celsius over the last century has reduced the annual water flow in the river by more than 11 percent. 

At least 40 million people are dependent on this river and a dying Colorado may seriously jeopardise their water supplies for agriculture and other needs. 

Other snow-fed waterways in the world are facing similar fate.  Another study had just recently flagged off the concern of shrinking freshwater resources because of faster melting of glaciers of Asia’s high mountain ranges including the Himalayas.  Data analysed show that the overall volume of meltwater rushing down the mountains each year from 2000 to 2016 was 1.6 times as much as it would have been if the system were in balance.  According to experts, glaciers do store water for decades or even centuries before releasing the same into rivers.  This helps water supply in the rivers even in drought years.  However, studies have found out that increasing temperatures are making glaciers melt faster than can be replaced by snowfall.  This could affect the water needs of about 221 million people each year by impacting the regional water security just within a few decades.

The rain-fed rivers face similar fate.  A study of Indian Peninsular rivers by researchers from the Indian Institutes of Technology at Indore and Guwahati, that has studied the climate resilient abilities of 55 catchment areas of 17 rivers, has found out that almost 60 percent of them cannot cope with the changing climate and may dry up soon.  In a previous study, researchers from IIT Madras and IIT Bombay had found out that some of the so called surplus river basins of the country are experiencing decrease in monsoon rainfall and hence may yield less water than expected.  The decrease in water yield in recent periods in major surplus basins has been more than 10 per cent in the case of Mahanadi and West Flow River-I. In the case of other surplus basins, the decrease has been within 10 per cent, pointed out the researchers. 

Redesigning development

In our constant obsession for a two digit economic growth rate the kind of development models we have promoted have done much harm to our rivers. Booming urbanisation, unsustainable agriculture, building dams, deforestation and over exploitation of groundwater have not only contributed to global warming, and have impacted the rivers at large, rivers but also have worked like local drivers to dry up rivers and reduced river flow.  This has jeopardised both food and water scarcity and has emerged as one of the greatest roadblocks in our way to achieve the SDGs. Our actions to solve some of these crises must therefore start from redefining the kind of development we have promoted in all these above sectors. 

Here comes the example of Cuban rivers.  A major investigation into quality of rivers in Cuba has pointed out, as reported in the Nature, that despite the island’s history of large-scale agriculture, the rivers studied had much lower levels of dissolved nitrogen — an indicator of fertilizer use — than did the Mississippi River Basin in the United States. The researchers speculate that this is due to Cuba’s transition to smaller-scale, more sustainable farming practices since the 1990s.

Agriculture is by far the largest water consumer, accounting for nearly 70 per cent of all withdrawals globally and as much as 90 per cent in some arid countries.  Redesigning our agriculture patterns and driving those to low-water intensive cropping patterns and phasing out from chemical induced farming can have a great impact on water flow of our rivers but also on quality of the rivers.  Similarly, tackling urban and industrial pollution can also have a major positive impact on our rivers. 

Dams do a huge damage to our rivers as well.  They obstruct the river flow and give rise to many of the other problems we have talked about.  There is a serious need to assess and understand the impacts of hydropower dam projects.  

A new research report launched by the WWF and The Nature Conservancy shows that of rivers measuring more than 1,000 kilometres in length just 37 percent remain free flowing. 

Obstructed rivers fail to maintain the vital ecosystems that are necessary for survival of riparian communities and other species, but also for ensuring sustainability of the river systems themselves impacting thereby the overall achievement of the SDGs negatively.  This report argues that solar and wind power and energy storage technologies can meet the world’s energy needs while preserving the health and connectivity of river systems. The report highlights the scope for renewables to serve developing countries while avoiding construction of hydropower dams on some of the world’s major rivers, such as the Amazon, Mekong, and Irrawaddy rivers. Free flowing healthy rivers are therefore beneficial in many ways. 

The article was first published in Urban Update