The development and application of a yardstick for water quality evaluation

For quality management of river water in India, a combined chemical, bacteriological and ecological yardstick was developed during a 3-year pilot study on the Yamuna River. This pilot project was performed as a joined effort of the Central Pollution Control Board, Delhi, India, and the National Institute of Public Health and Environmental Protection, Bilthoven, The Netherlands, under the auspices of the Indo-Dutch Cooperation Program on the Environment. The yardstick consists of eight indices (five concentration-oriented; three effect-oriented), reflecting different aspects of water pollution. Each of the indices will be derived from a set of one or more monitoring parameters that may vary according to regional requirements. All indices are calculated to fall in a numerical range from 0 to 100, where 0 represents totally unacceptable environmental conditions, and 100 stands for a pristine environment. The results of the monitoring activities are expressed in a single graph, called an AMOEBA (A Method of Ecological and Biological Assessment), that depicts the actual status of pollution in relation to target objectives. The targets will be set on the basis of an evaluation of ecological risk. Based on the above yardstick polluted stretches in the Yamuna River have been identified. For one season (October 1993–May 1994), the developed methodologies will be tested for sustainability in operation, while the proposed yardstick will be validated in different Indian river systems. The development phase of the project will be finalized by the preparation of a fully elaborate manual, which may also be of use to other countries setting up water quality monitoring and control strategies.