Contamination, Pollution and Quality

The report presents a review of several aspects of non-point source of pollution, like extent and effects of pollution in surface and groundwater bodies, pollution control, monitoring, modeling and management options. Non-point source pollution originates from diffuse land areas that contribute pollutants to surface and groundwater bodies. Sediments, nutrients and pesticides are transported from croplands either in a dissolved form in runoff or through adsorption onto eroded soil particles. Apart from this it can also enter groundwater through leaching.  

The report presents a literature review on the status of research related to saltwater intrusion and groundwater management in coastal and deltaic environments in the east coast of South India. The area is typically characterized by highly productive and alluvial aquifers and high use of both surface as well as groundwater. Seawater intrusion into the freshwater aquifers is extensive due to increased pumpages.

A quantitative understanding of the patterns of movement and mixing between freshwater and saline water and the factors that influence these processes is stressed in the report. It presents the mechanics of saltwater intrusion through studies by Ghyben and Herzberg and later on by Hubbert. A comprehensive review of studies by Reilly and Goodman relating to saltwater intrusion is discussed. Later advances in understanding saltwater-freshwater relationship through numerical models like sharp interface model and miscible flow model are described.

The study assesses the suitability of groundwater for drinking and irrigation use and examines the likely impact of Yamuna river water quality on groundwater. Delhi is faced with severe problems associated with groundwater quality and quantity. The quality varies spatially and seasonally, with depth and is primarily governed by the extent and composition of dissolved solids present in it. Surface water bodies play a role and the hydraulic gradient determines the lateral and vertical migration in the groundwater flow system.

Groundwater samples were collected through extensive field surveys covering entire Delhi area representing various geo-hydrological and land-use conditions. The data has been analysed with respect to BIS and WHO standards to examine its suitability for various uses. The area has a peculiar feature of infiltration of surface water to groundwater from river Yamuna and from various drains.

The study models the variations in water quality parameters of Yamuna river by means of stochastic approach using Central Water Commission’s monthly data for the period 1990-95 and makes projections for the year 1996. The results obtained for different water quality variables have been compared with the observed values and were found to be satisfactory. 

The study conducts an extensive water quality survey in sixteen reaches of Kali river in western Uttar Pradesh to estimate the inflow of two major nutrients (nitrate and phosphate) from point and non-point sources. The study intends to validate the present model based on the principle of conservation of mass and reaction kinetics phenomenon.

Data was taken for one annual cycle on a monthly basis and criteria developed to compute the non point source load from nine sub-basins in various stretches of the river. The computed loads at each section obtained from the predictive equation have been compared with the values observed in the field. The performance of the developed equation has been evaluated using percentage error estimation and correlation statistics. Remote sensing and geographical information systems (GIS) have been used to develop correlation between basin characteristics and non-point source loads.

These two documents from the KSPCB website, provide monthly water quality status data, for the rivers Tungabhadra, Cauvery and Kabini, monitored between January to June 2007, at various points along the rivers.

The data recorded are Temperature, pH, Dissolved Oxygen (DO), Biochemical Oxygen Demand (BOD), Chemical Oxygen Demand (COD) and Faecal Coliform.

Dear Users of IWP,

This field report describes the work of WaterHealth India (WHI), in organising safe drinking water using low-cost water purification units, in several villages of Andhra Pradesh. The work was taken up with financial support from IFMR Trust.

Vinjinampadu village in Guntur district, Andhra Pradesh, is one of the villages where WHI worked to establish the unit. The village had lacked potable water supply, because of which its people suffered from a range of water-borne diseases. The situation was similar in many of the other villages in which WHI initiated this work.

This paper by A Jagadeesh of RMK Engineering College, describes the design and testing of a portable, low-cost, and low maintenance solar disinfection unit, that can provide potable water. This system was tested with bore water, well as well as with waste water. In 5 hours, the unit eradicated 99.99% of the bacteria contained in the water samples.

This unit can provide about 6 liters of pure drinking water and larger units can be fabricated for providing safe drinking water at a community level.

Drinking Water Supply in rural areas of Assam ( India ) is managed by the Public Health Engineering Department (PHED), Government of Assam and the challenge is indeed enormous and achieving the targets requires well planned and strongly determined strategies and approach. Government has already formulated the necessary strategy to ensure sustained supply of safe drinking water in rural areas. However for achieving the desired end results from the Government initiatives, the community needs to be mobilized to own and sustain these programmes and to become an active partner in their implementation. For such a participatory demand driven approach, necessary awareness generation amongst the Community to realize the need for “total water security” and its impact on reduction of water borne diseases, is highly warranted.