Decisions of what type of energy resources we should invest in have long-term and large-scale impacts on the ecological quality of water and soil fertility. One issue, which is not very well searched, is the impacts of hydropower on the ecological quality of water that gives rise soil fertility. Both the ecological quality of water and soil fertility are very important for biodiversity and food production.

Hydropower is by definition a major interference in the natural hydrological cycle of surface water where erosion at up-stream high-land regions is essential process for promoting soil fertility in river catchments and river deltas in down-stream and low-land regions. In previous cases, e.g. the Aswan high-dam, the natural fertility at down-stream and delta areas was mitigated by heavy use of artificial fertilization. Artificial fertilization will not last for long-term as it is a non-renewable resource in addition to the long-term and large-scale environmental risks associated with it in terms of use and production.

In most of the energy debates the focus, so far, has been on reduction of carbon dioxide “green-house gas” so as to minimize the effect of global warming and its associated impacts. That is of course necessary but at the same time we have to consider other major impacts on the water cycle because of “Water-Energy Nexus” and in this context we have to take such aspects while we are about to implement policies for the use of “oil sand” or tar sand”. “Oil sand” or tar sand” is another case where in addition to risks for increased carbon dioxide emissions, there are clear negative impacts on water and ecological qualities.

Though the negative impacts of hydropower on ecological water quality and soil fertility may not be of the same dimensions as the benefits from hydropower, such impacts have to be taken in consideration for optimization of overall long-term and large-scale uses of “Water-Energy” resources. What we need to do is to have appropriate “Environment Assessment Analyses” and “Sustainable Actions” in place, so as to be prepared to deal with the growing degradation of water and ecological qualities.

http://www.dailytimes.com.pk/business/21-Jun-2014/world-bank-prefers-financing-hydel-projects