Ecological sustainability (consideration of ecological requirements)

Over a long period of time, mankind considered itself as all-powerful and able to bend nature to its will. However, instead of the slogan: “We cannot wait for favors from Nature …” has come the understanding that “a human being has got nature not as a gift from his ancestors, but borrows it from his descendants.” Such a concept adopted in the water sector, first of all, implies the recognition of rivers, lakes and other water bodies as “water consumers” along with other economic entities, and without specific ecological water flows they can lose their natural essence.

The environmental aspects of IWRM specify activities and awareness going in two directions: to prevent harmful events related to water resources, and to meet the water requirements of eco-systems. From the ecological point of view, the main features of water are its high mobility and ability to dissolve different chemical components of the natural complex. A key condition providing the sustainable natural and anthropogenic cycles is to minimize the negative impacts of interacting sources of water and territories in use, as well as the interaction of surface and ground water.

A number of the provisions that need to be considered in the practice of water resources management may be formulated from the positions of an ecosystem-defined approach.

1. In compliance with the IWRM principles, water, land, and other resources within a catchment area should be considered as components of joint use, management, conservation, and development. Responsibility and duties should be distributed among water users at national, sectoral, local and “bottom” level in such a way that the regulation of water demand and use would provide sustainable preservation and/or development of the natural potential as well as preventing its reduction. Based on those considerations, all water resources within the basin have to be considered in their interaction with economic activities, taking into account some limitations in use of water, land, and other resources, and reclamation measures in order to ensure sustainable development.

2. On the basis of the legislation, regulations, and international agreements, the State assumes the responsibility, with the assistance of its conservancy agencies, water management organizations and public mobilization, to monitor ecological and sanitary flows and the norms on preserving natural streams that were discussed above.

3. Step by step inclusion of the environmental component into IWRM in the form of the participation of conservancy agencies in decision making at all levels of the water management hierarchy as equal partners should be accompanied by the introduction of hydro-ecological management, as a top stage of IWRM.

4. Water resources management has to be based on the rigid principle of ecologically permissible water abstraction (EPWA) to prevent the possibility of irrevocable water consumption. When this level is exceeded (such a situation took place in the past), countries-consumers shall make their contribution to the international basin fund as a payment for excessive use of natural resources and implement mitigation measures.

5. For the purpose of preserving rivers and water bodies as natural ecosystems, drawdown of water of reservoirs and river flows should not be less in summer and more in winter than mean annual runoff (that is specified based on long-term flow rate measurements) in respective seasons. The observance of this rule can prevent transformation of rivers into runoff ditches. Water requirements of ecosystems in deltas and estuaries and flow-through and closed water bodies should be specified taking into consideration their bio-productivity and sustainability, based on monitoring data along with taking into account requirements of countries that are using water resources.

6. Environment aspects should be included into IWRM plans at the levels of basin, subbasin, and region. Ecological problems that need to be solved exist in each irrigation systems or WUA. These activities includes: (i) rehabilitation of disturbed natural landscapes due to water erosion, water logging, and deforestation; (ii) correcting such matters as excessive abstraction and use of local water sources; and (iii) inventory of sources of pollutants and damaged zones, and their control and localization.

7. Drainage and drainage water management is an important component of nature protection complex. The interrelations of surface water, groundwater, and drainage is a very sensitive aspect of water and land reclamation management because excessive water supply for irrigation or leaching of soils results in not only water losses and deterioration of water as a resource, but also degrades the land and loss of soil fertility. The incorrectly designed drainage systems mobilize vast volumes of salts from lower stratums. In addition, unevenness of irrigation and drainage results in increasing water losses and nonuniformity of crop over an irrigated area. In order to identify these shortcomings in water management in a timely manner, it is necessary to enhance the activities of land reclamation services, to equip them with relevant equipment and measuring instruments, to introduce GIS and remote sensing methods for monitoring and evaluation of land conditions. It is note worthy to remember that land salinization and water logging are some of the main factors causing decreased crop yield and water productivity in irrigated farming, because apart from the fact that there is a reduction in yield, water consumption is high.

It is clear that at present, water requirements of ecosystems cannot further be met according to “a residual principle” (delivering of residuary water after satisfaction of the economic needs). Meeting of water requirements of ecosystems should be one of priority activities within IWRM.

Source: V.A. Dukhovny, V.I. Sokolov, H. Manthrithilake, N. Mirzaev: Environmental Approach: Nature is an Equal Partner (2009)