Of late there is lot of awareness among rural population regarding the usage of toilets and related hygienic conditions. Government agencies and NGO’s are participating in a big way in this programme. Government of India initiated a program “Total Sanitation Campaign” (TSC) with the objective of eradicating the practice of Open Defecation by 2012. This programme has become part of rural water supply schemes for the past 5-10 years. Water supply schemes providing safe drinking water to villages and towns had priority in earlier schemes. But now, water and sanitation schemes are being contemplated simultaneously.
The objective of these schemes is to maintain adequate sanitation and provide safe drinking water to rural population. There appears to be a lot of progress achieved in sanitation and water programmes. In spite of commendable progress achieved in these schemes, surveys have revealed that even after a massive programme of toilets construction, there appears to be little change in the overall health status of public. As per the surveys conducted in Maharashtra, from 1996-97 to 1999-2000, more than 16 lac Latrines were constructed, but still there is very little improvement in the health sector, where the number of water borne diseases do not show any significant reduction in the subsequent years.
Table 1: Status of water borne diseases in Maharashtra
Disease | 1999-2000 (Attacks) | 2000-2001 (Attacks0 | 2001-2002 (Attacks) |
Gastroenteritis | 65,067 | 32,479 | 67,295 |
Diarrhoea | 10,23,194 | 11,46,395 | 11,04,841 |
Inf. Hepatitis | 16,159 | 13,343 | 12,066 |
Typhoid | 13,079 | 15,438 | 13,320 |
Cholera | 348 | 1,043 | 1,326 |
Source: Drinking water and sanitation in Rural Maharashtra: A review of policy Initiatives By Shree Keshab Das
Despite spending crores of rupees to contain water pollution, water samples are continuously failing to meet the prescribed quality standards. Same situation and conditions exist in other states.
Probable Reasons for Poor Groundwater Quality
The risk of contamination is greater in the areas where shallow groundwater conditions exist. The Central Groundwater Board maintains National Network Observation Well data Water Level Information gis2.nic.in/cgwb/Gemsdata.aspx). As per this data, it is observed that in Andhra Pradesh state, as against 693 number of observation wells (generally one observation well represents one mandal having average of around 20 villages in Andhra Pradesh; in other states, Taluks and Blocks are common where more than one observation is established to monitor the seasonal water levels), 113 number of wells recorded 0-2 meter water level below ground level during rainy season. District wise details of shallow groundwater conditions (0-2m bgl) are given below.
Table 2: Shallow Groundwater Conditions
SL.NO | Name of District | No of observation wells taken for analysis | No of wells in the range of 0-2 m water level during rainy season | Probable reasons for near Ground level water table conditions during rainy season. |
1. | Srikakulam | 50 | 9 no obs wells | Groundwater exploitation is low,hilly area more |
2. | Vizianagaram | 24 | 10 nos | ---Do---- |
3. | Visakhapatnam | 46 | 3 | Half of the area is tribal, other half well developed in irrigation. |
4. | East Godavari | 74 | 22 | Delta area, along the River Godavari and Canal command area. |
5. | West Godavari | 62 | 15 | Along the River Godavari with canal net work. |
6. | Krishna | 67 | 13 | More delta area. |
7 | Guntur | 95 | 13 | Along River Krishna and canal net work. |
8. | Prakasam | 34 | 3 | Sea coast and valley fill areas |
9. | Nellore | 68 | 5 | Sea coast and valley fill areas |
10. | Chittoor | 96 | 1 | Valley fill area |
11. | Kadapa | 77 | 1 | Foot hill zone and valley fill area |
12. | Anantpur | 26 | 2 | Valley fills area. |
13. | Kurnool | 41 | 5 | Eastern portion dotted with hills.valley fill area and foot hill zone. |
14 | Hyderabad | 34 | 5 | Near surface water bodies. |
15. | Rangareddy | 95 | 7 | ------------do---------------- |
16. | Medak | 24 | 4 | Near surface water bodies and foot hill zone |
17. | Mahabubnagar | 32 | 8 | ----------------do------------------------- |
18. | Nalgonda | 70 | 5 | ----------------do------------------------- |
19. | Nizamabad | 28 | 5 | ----------------do------------------------ |
20. | Warangal | 94 | 11 | Eastern portion hilly.valley fill and foot hill Zones. |
21. | Karimnagar | 44 | 7 | Soft rock area and hilly terrain in Manthani and Mahadevpur areas. Canal command and Foot hill zones. |
22. | Khammam | 50 | 8 | Major sedimentary rock terrain. River Godavari is flowing. Tribal area is more. Valley fill, foot hill zones and along major streams. |
23. | Adilabad | 81 | 14 | Tribal and hilly area more. Along the river, foot hill zone and valley fill areas. |
Data based on 2008 and 2009 calendar years.
In the above data, observation wells where the depth to water level during rainy season is 0-2m, are susceptible to groundwater contamination from septic tanks. During rainy season, there is a possibility of mixing of groundwater, drainage water and effluents from septic latrines. In such conditions, water borne diseases affect the villagers who depend on groundwater for drinking water purpose. Water-borne diseases affect the occasional guests, who visit their native villages after spending long time in cities where safe drinking water is available, and floating population. Contaminated water affects the children, old people and occasional guests more when compared to the others. Probably local residents develop immunity to accept contaminated water.
Similarly, in other states also (source: Groundwater Scenario of India 2009-2010 CGWB year book), 4% to 75% of observation wells recorded 0-2m depth to water level during rainy season. The highest percentage is in Assam and lowest percentage in Delhi. Karnataka state recorded 20% of observation wells, TamilNadu 5% observation wells; Maharashtra 31% of observation wells recorded the depth to water level from zero to 2m below ground level during rainy season. The near ground level water table record particularly during rainy season in Delta areas, along the major Rivers, Canal and Tank command areas, Buried pediments, Valley fill areas, Tribal and Forest areas where groundwater exploitation is low to negligible. In absence of underground drainage system, groundwater contamination is possible due to numerous types of human activities such as
1. Residential
2. Municipal
3. Commercial
4. Industrial and
5. Agricultural activities.
Water Related Diseases Due to Microbial Contamination
Water-borne diseases are Viral, Bacterial, Protozoal and Thread worm
Microbial drinking water quality test is very important at the Source and Point of abstraction. Household containers also spoil the water quality. Monitoring of drinking water catchment, point of abstraction and container water quality also should be carried out to find out where the contamination of groundwater took place and level of pollution at different places i.e at source, point of abstraction and in water containers.
Bacterial indicators E-coli, Thermo tolerant coli presence in drinking water indicates contamination. E-coli are derived mostly from human and animal faeces. Thermo tolerant coli grows at 44 degree centigrade. Faecal Streptococci is an indicator of faecal pollution, and survive longer water environment than E-coli.
REMEDIAL MEASURES