Water Quality in the Rural Drinking Water Supply has emerged as a major issue. There was no proper emphasis on water quality till the end of the 6th Five Year Plan and even in the Seventh Plan before launching the National Drinking Water Mission in 1986.

The primary objectives of the National Drinking Water Mission set up in 1986 was to improve the performance and cost effectiveness of the on-going programmes in the field of rural drinking water supply and to ensure the availability of an adequate quantity of drinking water of acceptable quality on a long term basis.

The primary objectives of the Mission included monitoring the quality of water after identification of problems, tackling the same by the application of science and technology to ensure that the water available is of acceptable quality and ensure that the quantity and quality of water is sustainable on a long term basis by proper water management technique and implementations of management information system.

The secondary objectives of the Mission included survey of various kinds of water sources, prevention of pollution of drinking water; and educating the public in conservation of the quantity and quality of water through awareness campaigns, community participation and health education programmes.

Drinking water problem is not only in terms of availability of quantity but also quality of the water available. Rural drinking water supply is to a large extent dependent on ground water (85%). Though ground water is less susceptible to pollution as compared to surface water, the nature of quality problem in ground water is of two types: (i) It is inherent in the form of contamination caused by the very nature of geological formation, viz. excess fluoride, arsenic, brackishness, iron, etc. (ii) Ground water pollution caused by human intervention (anthropogenic) viz. nitrates. 15 per cent of the rural water supply comes from surface water sources. Major quality problem for surface water is seasonal turbidity. Water also suffers from bacteriological contamination, reasons being anthropogenic.

The reasons for chemical and bacteriological contamination are: poor hygienic conditions around the water sources, improper disposal of sewage and industrial waste water, callous disposal of solid waste, indiscriminate use of chemical fertilizers having high quantity of Nitrates used in the agricultural sector, pollution from industrial effluents (untreated), over-exploitation leading to quality degradation, pollution of the source due to ignorance of the people, over-population and lack of public awareness.

Water Quality Monitoring & Surveillance Programme

Water Quality was accorded high priority in the Mission. Parameters and safety standards on water quality have clearly been laid down, not only in the Mission document, but also in the Manual for drinking water supply and the health standards. A beginning was made by undertaking water quality analysis in the Mini Mission project areas by NEERI, Nagpur; ITRC, Lucknow; BARC, Bombay and the limited facilities available with the concerned States. There was no systematic arrangement for Water Quality Monitoring & Surveillance. A regular programme for WQM&S - an important priority in the Mission, was launched by initially setting up State and District level water quality testing laboratories with the ultimate aim to provide safe drinking water and generate awareness about water quality among rural masses.

With the launching of Water Mission, many States desired to strengthen their existing lab facilities in terms of meeting the additional requirement of water quality testing and induction of modern equipment for these labs. The objective of the WQM&S programme was to develop an integrated system by setting up of district level labs for water quality testing, reporting and generating awareness in rural masses about the importance of water quality and its relation to health.

The document prepared for this purpose - Executive Guidelines for Implementation of Water Quality Testing Laboratories gives details of the objectives of the programme, an approach and methodology, manpower development, awareness campaign, community participation, sanitation and health aspects, a time bound implementation programme and the outlays involved. The main constraints involved in establishing water quality laboratories relate to non-availability of suitable buildings for locating the laboratories, resource crunch in the States for creation of posts to man the laboratories and to meet the capital and recurring cost, lack of proper management, proper transportation for collection of water samples in remote areas and villages, transportation of water samples to the Central sample testing point within the desired time, non-availability of qualified and regular staff, difficulty in regular supply of chemicals and lack of inter-departmental coordination. All these aspects have been kept in view and corrective measures suggested in the document to overcome these difficulties. Government of India sanctioned 430 district level laboratories out of which 252 have been established till date. State Governments and other organizations have established 158 labs making a total of 410 labs in existence till date. It was proposed to provide one laboratory in each district of the country. Twenty-two mobile laboratories have also been provided to various States. Initially, 85 stationary district level labs and 15 mobile labs were set up. Preference was given to Mini-Mission districts for locating these labs. Break-up of labs is given in Annexure I.

First Water Quality Survey

For ascertaining the magnitude of the quality problem, a survey of drinking water problem habitations was undertaken in 1991, based on 1% random sampling. This was validated in 1994 and updated in 1999. As per results of this survey, a total of 2,16,794 habitations were found having water quality problems, with break-up, as on 1.4.1999, as follows: Fluoride 36,998, Salinity 32,597, Iron 1,38,670, Arsenic 4003, Others 1400. State-wise details of Ist Survey are given in Annexure 1.

Sub-Mission Projects

For fulfilling the Mission's objective of providing safe water to rural India exclusive Sub-Missions were constituted for initiating both preventive and remedial measures for water quality problems, for ensuring safe drinking water to quality affected habitations. The Government of India supported all quality based Sub-Mission projects to the extent of 75% of the cost leaving the balance 25% to be borne by the State Governments. A number of projects were sanctioned from the Mission between 1992-93 and 1994-1998 (details in Annexure I and II). The following Sub-Missions were initiated -

(i) Eradication of Guinea worm

Guineaworm is a water-borne disease caused by dracunculiasis medinensis. Efforts to control this disease were started in early eighties. It is a good example of how the coordinated efforts of organisations like National Institute of Communicable Diseases (NICD), RGNDWM, International organisations like WHO, UNICEF, and State Health & PHE departments could attack and eradicate an otherwise difficult problem. India has been certified as free from Guinea worm disease in the meeting of International Commission for Certification of Drancunclasis (ICCDE) held at World Health Organization, Geneva, during 15th-17th February, 2000.

(ii) Control of Brackishness

Excess brackishness causes the problem of taste and has laxative effects. Control measures include either providing alternate sources free from brackishness or supply of water with total dissolved solids within permissible limit of 1500 ppm (parts per million) by treating brackish water with the help of treatment processes like reverse osmosis, electro dialysis, etc. For treating brackish water, 194 desalination plants were approved by the RGNDWM and 150 plants have been commissioned.

(iii) Removal of Excess Iron

Excess iron in the drinking water is prevalent in the North-Eastern States. Consumption of water with excess iron causes constipation accompanied by other physiological disorders. Control measures include providing alternate sources free from iron or treating iron contaminated water (to within permissible limit I ppm) with the help of iron removal plants. For treating iron contaminated water, 16415 plants were approved and 9355 plants have already been commissioned.

(iv) Control of Fluorosis

Excess fluoride in drinking water causes dental and skeletal fluorosis. The problem is prevalent in 150 districts of 17 States of the country. Control measures include providing alternate sources free from fluoride or treating fluoride contaminated water (to within permissible limit 1.5 ppm) with the help of treatment processes such as Nalgonda technique or activated alumina process. So far, 499 plants (fill and draw type and handpump attached type) have been approved by the Mission of which 427 plants have been installed.

(v) Control of Arsenic

Contamination of ground water with Arsenic was first noticed in 8 districts of West Bengal, in the early 80s. The first attempt to tackle the problem was made by the Government of India in 1988 by sanctioning an investigation project. Thereafter, the Government of India has sanctioned several R&D projects as well as field-oriented projects in the arsenic affected areas.

Among the various techniques in vogue for removal of arsenic, two methods, viz., (i) Co-precipitation technique and (ii) Absorption technique, are the most common. The PHED and other organisations like the All India Institute of Hygiene and Public Health (AIIH&PH), Calcutta (based on co-precipitation technique) and Bengal College of Engineering, Howrah (based on absorption technique) have also installed arsenic removal plants which are reported to be functioning without any major complaints. Besides, domestic filters have also been developed by these organisations.

Before 1994, 20 projects were sanctioned for Andhra Pradesh with a total cost of 11420.80 lakh with GOI share of Rs.8547.17 lakh. Only one project was for brackishness and the balance 19 were for fluoride. All these have been completed.
Between 1994-98, 100 projects were sanctioned with a total cost of Rs.1,22,755.62 lakh with GOI share of Rs.92,091.29 lakh. 76 projects have been completed so far.

With effect from 1.4.1998, powers have been delegated to the States to plan, sanction and implement Sub-Mission Projects . No separate allocations are made to the States for this purpose. States can utilize upto 15% of their annual allocation under ARWSP for taking up projects under the Sub-Mission Programme. More funds can be utilized by those States which have fully covered their habitations by the stipulated norms for drinking water supply with the specific approval of this Department.
A number of State Governments have reported sanctioning of Sub-Mission projects after 1.4.1998.