Saturday, February 29

The clock is ticking down for the world’s major rivers

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The Roman aqueduct at Pont du Gard is one of the best preserved.

OUR rivers are running out of time. Water is the major source of all life and has been for millennia. Once our rivers were abundant in fish, other aquatic creatures, and fresh water, but in our geological Anthropocene era, we have created our own manmade problems. Many of the world’s major rivers are cluttered with filthy, toxic detritus dumped by human waste, in excreta, plastic, and any other disposable waste as, alleged intelligent mammals, we choose to dispose of.

Ancient civilisations, such as those along the River Nile, existed because of their close proximity to water which they carefully utilised for irrigation purposes. The Roman Empire again thrived on river supplies and created stunning aqueducts for the transport of water supplies to major cities. In Southeast Asia, the ancient Laotian and Khmer civilisations thrived along the banks of the Mekong. Major European and Asian cities are split into two parts necessitating bridge links, such as Paris, London, and Budapest and, more locally, Kuching, on respectively the rivers Seine, Thames, Danube, and Sarawak.

Certainly, in Medieval times, European rivers became the cesspits for human excreta and in the 19th century for the disposal of industrial waste. These problems are echoed around the world today and why? The pertinent answer is related to the exponential growth of the world’s population, which has been compounded by city growth and inadequate planning procedures to dispose of waste products. These are the problems our rivers still face.

Natural beauty of river basins

River and their drainage basins have long provided mankind’s existence and before national boundaries were subsequently created. Perhaps, Sarawakians and Sabahans do not realise the tremendous beauty of the sparsely populated upstream reaches of their major rivers for, not only the difficulty of the terrain in reaching these upland areas, and also the fact that most of the population live in downstream areas near the coast. The upstream reaches are relatively unaffected by pollution, which rapidly increases as the rivers progress downslope to the lowland areas.

Throughout the world, the creation of hydroelectric schemes has displaced local inhabitants as their villages have been submerged behind huge dams to hold water for HEP generation. Such highland people have paid a personal cost. Whilst I do not criticise the creation of clean green energy to reduce carbon dioxide emissions and supply nations with cheaper forms of electricity, an environmental cost is also paid in loss of habitat to people, animals, fish, and plants.

In the fullness of time, in a river’s upstream reaches, where such manmade lakes exist, water sport venues may develop bringing in some income to local people if employed in those industries. Such lakes, however, are sediment traps thus depriving downstream communities in lowland rice growing countries of the vital annual replenishment of soil nutrients in times of flooding. Most Southeast Asian countries depend upon ‘wet’ rice for sustenance.

Are the ‘rice bowls’ of Asia’s rivers being gradually destroyed?

To give readers a mere glimpse of the problems that lowland rice farmers face, I shall concentrate on the mighty Mekong river, which flows for nearly 435,000km from the melting snows of the Tibetan Plateau, through southwestern China, Myanmar, Laos, Thailand, and Cambodia to its delta in Vietnam before entering the South China Sea.

Along its course, it has been estimated that, in ‘normal years’, over 100 million tonnes of rice is produced, providing an income to 70 million people through food and river fish, let alone a surplus of rice for export. However, as now we have learned to accept, climate change has thrown the monsoon seasons out of kilter with severe drought hitting many countries along the course of the Mekong. To add to this, several Asean countries, in a recent meeting in Thailand, are blaming China for what they refer to as ‘dam politics’. To study the scale of dam construction, along the course of the Mekong, just scan the statistics.

Most Southeast Asian countries depend upon ‘wet’ rice for sustenance.

Cambodia is not without a smirch in its plan to build an 18km-long dam to trap this river’s water thus depriving the lower Mekong peoples. In Laos, a new dam constructed by a Thai company will sell over 90 per cent of its electricity generation to Thailand!

Undoubtedly, the benefits of any HEP building scheme flows into investors and urban areas and often to the detriment of rural communities along the course of such rivers as water levels fall. Along the Mekong, this year’s drought has compounded the difficulties that lowland rice farmers now face.

Ecological and environmental changes

With further climate changes the life style of many riverside dwellers will also change. Egypt has already experienced a loss of river sediment in the Nile Delta as tidal currents are removing the delta faster than the sediment is being replaced. This is due to the construction of upriver dams not only in Egypt but in adjoining countries through which the Nile flows.

With less river water downstream and a fall in the level of the water tables and ever-rising sea levels, delta areas are facing an incursion of seawater and increased salinity of once highly productive farmland. Plants and animals are also affected when their natural habitats are being destroyed. Bird migration routes are also changing.

Have governments in countries along which major river basins exist really considered the effects in their surge for economic development and the effects of exploiting the stretch of such rivers in their own domain upon neighbouring down river countries and their people’s way of life? All river basins, whether within countries or part of other nations, need holistic management from the source of the river to the very point that it enters the sea. Currently, it appears that we are creating anthropogenic stresses on the vital waterways of our world and desperately need to revere our rivers and use them wisely.

Is it beyond the wit of our world leaders in the 21st century not to appreciate historical mistakes from the mismanagement of huge river basins and the consequences, we now face, in damage to the natural environment and to human livelihoods and lives? Our major rivers were there before national boundary lines were ever demarcated but until nations learn to speak with other nations about their proposals for the usage of major rivers, these rivers will run out of time.