Meaningful World

One very disturbing facets that came to the fore at this hour is that times are changing and though financial well being is there the humanity factor is missing – human slowly turning to cyborgs. The path of success is so ruthless that people even do not think twice to dismiss the contribution of their elders and so also the teachers who shaped them to what they are today. These self glorifying egomaniacs even dare to the extent of hurling nasty abuses to the people who made their life possible like a bed of roses. When shall they acknowledge these wonderful selfless people ?

The lure of a high life beckons us all. The path is not simple, some are ready to compromise some are not. The middle class morality syndrome do bogs us down to some extent. When one look at the three basic civic necessities “Roti, Kapra & Makaan” it is very well understood that none of them are easy these days. If I may be permitted to extend the list I would say that health, education and housing are today the most lucrative sectors. To achieve them to a so called respectable extent either you steal or become stale. Things like honesty, dedication, social responsibility are slowly becoming extinct breed of character traits. But then, exceptions are always there and that do help to keep the wheels of hope running. As one of the esteemed bloggers have put it so well “Simplicity is the ultimate sophistry”.

Technology was supposed to make our life easy and not lazy and that’s the ultimate paradox. Every modern invention comes with its own side effects. We have forgotten to enjoy good books, good music(I mean music and not noise), spending quality time with family members, visiting old friends and relatives, enjoying simple pleasures of life, being punctual. A host of modern gadgets have made us pre-occupied to the hilt. Perhaps someday we will forget to do a simple mathematical operation also. Calculators / computers / mobiles etc. are there take care of that and we are enslaved to it. The stress of this rat race gave rise to a lot of physical and psychological problems unheard till not so long ago. “Occupational hazards” as they frame it. That in turn is an enviable revenue earner for a lot of so called successful professionals.

I do not mean to sound pessimist but do we really care? After all the Industrial revolution, Green Revolution now it seems we need some kind of Mental Revolution. Is someone really listening???

When Alone

For the past few weeks, I was felling very dejected. The last week during the Durga Puja was probably the nadir of it. The fact that my wife and my daughter is away to her fathers place made the house feel empty. The emotions of a parent are really best understood by anyone only after becoming a parent oneself. If I may be permitted to quote a famous Bengali poet of all times “Ki jatona bishey, bujhibey se kisey; kobhu asibishe donsheni jarey” (Literal translation : How will one understand the pain of poison if he has never been bitten by a poisonous snake) .

All these times my only solace that I was under the caring presence of my mother, who despite herself being ill and saddened(after the demise of my father, last November in Durgapur, suffering from acute pneumonia and septicimia) took pain for all it needs to make me smile. The emotions that plays in her mind are seldom understood, let alone being appreciated by anyone. They say that time is the best healer and you must forget your past and look beyond – I agree. The daily commitments and hard reality of life forces you to forget a lot of sad memories. But as Shelley puts it ”Our sweetest songs are those that tells of saddest thoughts” – the emotions keep stirring inside you all the time, whenever there is time. The best example is a comment by an English doctor Sir James Hutton – “Present is the key to the past”, which forms the basis of our knowledge of the Geological History of Mother Earth.

During the puja festivities, I have tried to keep myself immersed in the puja editions of various Bengali periodicals, catch up and keep in touch with my past and the present peers. One very encouraging thing that happened during my net surfing regime in these days is that I got in touch with a lot of my old friends, colleagues and teachers. The affections, the camaraderie were intact even after such a long hiatus. The moments of sharing, learning, the frustrations of failure, the pride of a job well done - somehow remains intact in our memories even after so many years. Is it some how the tale tale signs of progressing age or otherwise, I really don’t know.

ARTIFICIAL RECHARGE TO GROUND WATER – Common Man Speaks

Nowadays, Artificial Recharge to Ground Water is a hot topic of discussion among scientists, technicians and intellectuals. They think it is the ultimate solution to meet up the water crisis and should be implemented pan- India immediately. Why immediately - when it is an age old practice?

The artificial recharge to ground water is in vogue from time immemorial. As soon as people learned agriculture, the process of artificial recharge was initiated. Ploughing of land for sowing of seeds heralded the initiation of artificial recharge in the very early days of human civilization. The process of artificial recharge increased with the expansion of the agricultural activities. Subsequently the artificial recharge was geared up when the agricultural land ownership was admitted. The present day fragmented land holding has led to small agricultural plots having low rising bunds all around. Apart from this, the field are having step like disposition particularly in undulating / sloppy terrain. These bunds and step like features helps to arrest rain water and also spilling over the excess water to the next field which facilitates the process of artificial recharge since a long time.

It is said that expansion of towns and cities reduces open areas resulting in lower scope for ground water recharge through rainfall. The question that immediately follows this is that whether there has been any scientific proof or work carried out particularly in this regard for any of the cities / towns, any where in India or globally or it is just a mere guess work of the scientific fraternity. On the contrary, the expansion of cities may also help in increasing the scope of artificial recharge instead of reducing it. The land developed for dwelling purpose normally reduces surface run off rate of rain water which other wise would have flowed unabated to the drainage channels. The boundary walls constructed around the large number of dwelling units and thousands of vacant small plots hold the rain water for considerable time and this increase in residence time actually should recharge the ground water to a greater extent than it would have earlier.

A majority of the present day scientists, intellectuals and surprisingly lot of our law makers opine that roof top rain water harvesting must be made mandatory for every building in urban and rural areas including individual dwelling units with a view to recharge ground water zones artificially. But the rain water is normally acidic and in big cities / towns it contains a large number of harmful / unavoidable elements resulting from the widespread urbanization / industrialization phenomenon. When the rain water percolates through the soil zone through its natural course of movement, it gets modified chemically before reaching the ground water zones and becomes fit for consumption. But if the same rain water is injected to the ground water zones through recharge pits / shafts, the scope of modification becomes less and in the long term may have some adverse effect on the ground water quality. More over, every caution has to be taken for selecting the site of recharge pit / shaft etc to avoid mixing of sewerage water etc with the recharge water. This needs proper guidance and constant vigil through a large number of technically competent persons. Apart from these, the entire system of harvesting and recharge structures needs periodic maintenance, which involves huge cost. More over, roof top rain water harvesting and artificial recharge in a large scale is a definite violation of the natural system. The future impact of this is also unknown. Though encouraging results have been achieved in isolated cases or in small areas, till date no proper documentation is available for project of large scale. Hence every caution has to be taken before implementation of any such large scale scheme.

DISCLAIMER : This is a compilation of the discussion and feedback received from common people, mostly from the non-hydrogeological background and I have merely contributed as a compiler. This article does not in any way reflect my personal opinion or the organization I work for.

GROUND WATER HYDROLOGY – Perspective of a common man

INTRODUCTION : Ground water plays a vital role to supplement water requirement for domestic, industrial and irrigation fields. Its use has gained an increasing popularity over the years, because of various factors like easy accessibility to this resource, its ubiquitous nature of occurrence and high use efficiency. Further the construction of ground water structure is mainly through individual’s investment and or with the credits from financial institutions. Presently, at about 52 percent of irrigation requirement is being met from ground water source.

Considering the above facts, central and different state organizations dealing with ground water have already undertaken assessment of ground water resource availability and also monitoring of ground water regime periodically both quantitatively and qualitatively. Along with these, efforts are also being taken up for augmentation of this resource through artificial recharge. But assessment procedure, quality monitoring scale and artificial recharge practices etc contain some flaws and these flaws are being discussed here briefly.

RESOURCE ESTIMATION : Ground water resource may be divided as dynamic and static resource. The resource, which occurs within the zone of water table fluctuation with respect to pre and post monsoon season is termed as dynamic resource. This is generally replenished in every year mainly through rainfall recharge. The static resource occurs below the zone of water table fluctuation. In the existing practice assessment of dynamic resource gets more importance than static resource and available dynamic resource is mainly taken into consideration for preparation of any development plan and also to determine irrigation potential to be created from ground water source. But as a matter fact, major part of dynamic resource cannot be used to fulfill any requirement. Because, like surface water, ground water, always flows sub - surficially to the down gradient i.e., towards lesser potentiometric head. This sub-surface flow of ground water either crops out as base flow of rivers and streams or flows directly into sea or lakes etc. The ground water maintains the flow of rivers and streams when there is no rain particularly in those areas where rivers are only rain-fed. This continuous discharge of ground water is reflected on the water table in the dynamic resource zone. The gradual depletion of ground water table from post-monsoon to pre-monsoon periods is due to natural discharge plus withdrawal of ground water through man made ground water structures for different purposes. Natural discharge creates normal fluctuation in dynamic zone and withdrawal of ground water takes place from below normal fluctuation zone i,e from static resource zone. As the depleted zone is replenished by monsoon rainfall, the entire zone appears to be dynamic zone, though as a matter of fact this zone contains normal zone of fluctuation plus part of static resource zone. This fact can be established if we study the water table fluctuation (pre & post monsoon) in such areas where stage of ground water development is negligible. It has been noted that in such areas also in spite of negligible draft water table fluctuation attains a considerable value. This fact indicates that ground water of natural/ normal dynamic zone either crops out as surface water resource in streams, rivers and simply occurs as seepage on ground surface or flows sub - surficially directly into the sea, lake and ocean depending upon the water table configuration in any river basin. Any withdrawal of ground water affects the resource of the zone, which occurs below normal fluctuation zone and withdrawal of ground water increases the downward extension of normal dynamic zone. In the existing resource assessment practice the resource of natural / normal fluctuation zone is also accounted as utilisable ground water resource. But as a matter of fact the utilisable ground water is available only from below natural / normal fluctuation zone. Part of the ground water of natural / normal fluctuation zone when cropped out as surface flow in rivers and streams is considered as surface water resource.

GROUND WATER REGIME MONITORING : The main objective of monitoring is to keep a vigil on the ground water regime and it is generally being done through permanent hydrograph stations, which are generally open or dug wells and also piezometers. The open or dug wells are being used for monitoring of ground water of phreatic / shallow zone and piezometers for deeper zone. As a part of monitoring, depth to water level data from the stations, are collected either four times (Jan, Apr / May, Aug, Nov) or tow times (Pre &Post monsoon) in a year. In some special cases the stations are being monitored more than four times in a year also. One of the main purposes of collection of water level data is to study the long-term trend of ground water table (rise / fall) with a view to keep a vigil on the ground water regime quantitatively. It has been noted that as a general practice, trends are determined mainly in following two ways to predict the water table behaviour,

1.Using all the water level data of some continuous years irrespective of months or periods, or
2.Using only pre-monsoon water level data of some continuous years.

If the water level trend derived from above two methods shows any falling trend, consternations are raised, by declaring that ground water table is falling. But in reality it is not the fact. Because the trend which has been obtained by using all water level data irrespective of months or periods practically does not give any concrete information regarding the behaviour of water table. Trend should be prepared considering water level data of a particular period or season over the continuous years to get an idea on configuration of water table for that particular month / period over the years. The falling trend of pre-monsoon period also may not have much importance unless and until post-monsoon period water table show any falling trend during same years. No fall in water level trend in post-monsoon period and falling trend in pre-monsoon indicate that though there is a gradual increase in ground water withdrawal has taken place over the years but the aquifer is being fully recouped every year during post-monsoon period and for which the post–monsoon period water level remained unchanged .The falling of pre-monsoon trend may increase the cost of ground water withdrawal only .The falling trend of water table during post-monsoon period matters, when there is not much variation in monsoon rain fall over the years under consideration. This falling trend during post-monsoon period indicates that magnitude of withdrawal has gradually exceeded the quantity of available in an area and quantitatively the ground water regime of the area is under stress.

ARTIFICIAL RECHARGE : Now a days much stress is being given on artificial recharge of ground water to augment the ground water resource. The artificial recharge is being advocated to implement everywhere. But it is to be kept in mind that artificial recharge will not be effective in such areas where rainfall is fairly good and also terrain condition offers fair scope of infiltration. It is a well known fact that aquifer rejects excess rainfall recharge after it attains complete saturation. Moreover continuous recharge may create problem like water logging, which is a common phenomenon in major surface irrigation command areas. Hence this artificial recharge technique should be applied mainly in such areas where
1.Rainfall is low and or water table is deep either in pre or post-monsoon period or in both periods
2.Declining trend of water table has occurred during post-monsoon period

The roof top rain water harvesting, a new approach in artificial recharge technique is slowly gaining much importance. It is advocated that in towns and cities rain water falling on the roof of buildings should be used for artificial recharge through some recharge pits, bore holes and dug wells etc. In this case besides rejected recharge factor, another problem related to quality may also arise in future because of following reasons.

The rain water in general is acidic and acidic nature is modified during sub-surface infiltration of water through soil zone and unsaturated part of aquifer during normal infiltration process. It is a very well known fact that rain waters of cities, towns and industrial areas are more acidic than other areas due to so many factors. Hence, if these more acidic waters are injected directly through recharge pits or tube wells etc, the chances of modification of acidic nature of water becomes much less and this may lead to serious quality hazards in future resulting ground water unfit for use. Necessary treatment of rain water is needed for reduction of acidity before injection.

CHEMICAL QUALITY : Concentration of different chemical constituents in water not only determines its fitness for utilisation but also defines its fitness for different uses like domestic, agriculture and industrial etc purposes. In this process limit of concentration of different chemical constituents for drinking water has been fixed in different countries. To determine potability of ground water in India the BIS standard (BIS:10500,1991) is normally followed uniformly for the entire country, though the wide variation in geographical condition and also in food habit of habitants are found in different parts of the country. The variation in geographical conditions as well as differences in food habit certainly create different tolerance limit of the habitants of different parts. Hence, the regionalisation of drinking water standard is required instead of single uniform standard for the entire country. During fixation of standard, along with the upper limit of concentration the lower limit of concentration of the chemical constituents particularly which are vital for human health may also be prescribed, because excess fluoride is harmful but side by side complete absence of fluoride is not also good. There should not be both desirable limit and permissible limit, because limit should have single value when human health is concerned and as usual this limit may have some percent variation either on positive side or on negative side depending upon the health constitution of individual inhabitants of a particular area.

SPACING CRITERA:The norm of spacing between two energized ground water withdrawal structures has been fixed to regulate ground water withdrawal with a view to avoid mainly overexploitation and also to create scope for having legal/ equal share of ground water by all users. In this process, it is suggested that the distance between two energized irrigation dug wells may not be less than 100m. Side by side it has also been prescribed that the tentative command area of an energized irrigation dug well, on an average, is around one hectare i.e, 100m x 100m area. Considering this command area of a dug well, it may be conceived that, the above prescribed spacing norm for dug well may not have much practical importance. Because, size of agricultural land / plot under individual holding in an area is found to restrict within one hectare in the majority of the cases and agricultural plots having sizes varying from 0.4 to 1.0 acre which is much less than 1hectare, are very common .The water requirement is more or less same to irrigate an area of one hectare and 3 to 4 adjoining agricultural plots having cumulative total of one hectare area. Hence construction of more than one dug well to irrigate one hectare of land matters little so far the ground water draft is concerned. More over, field experiences indicate that the pumping effect in a dug well is hardly felt beyond 20 to 25m distance. The similar type of situation (command area: plot size) also exist in the case of other ground water structures, particularly for filter point and shallow (low duty) tube wells. This reality has to be given proper weightage while fixing the spacing norms, so that small plot holders may not be devoid of their rights to have own ground water structures on the plea of spacing norm.

The depth criterion is more important rather than horizontal spacing for structures like tube wells not only to minimize interference of pumping but also to minimize the chance of over exploitation of a particular aquifer. Fixation of depth range of aquifer zones (water bearing horizon) to be tapped by different type of tube wells like filter point, shallow, medium deep and deep tube wells will restrict tapping of same aquifer zone simultaneously by different types of tube well. Also tapping of same aquifer zone by same type of tube well within short distance should not be allowed and in this case horizontal spacing norm is required and this is to be fixed after considering the different technical and non technical aspects.

The revision of existing spacing norm in the light of above discussions is very much necessary because within next few years most of the State Governments may implement ground water law. In the absence of revised spacing norms ground water users may face problems in coming years for construction of ground water structures.

USE OF DIFFERENT TERMS : Now-a-days different terms like Watershed, Lineament, Schist, Gneiss, etc are used in different literatures in such a way that these may create confusions. The term ‘Watershed’ is very often mixed up with river basin and notion like ‘watershed management’, ‘watershed development’ etc, are being used. But the literal meaning of term watershed is the line dividing two rivers / rivulet / stream or it is the boundary line of a river basin and in any case the terms, ‘watershed’ and ‘river basin’ are not synonymous. Hence it is more appropriate to use the term river basin while using notations like, ‘river basin management’ or ‘river basin development’ etc and prefix like micro, macro, and mega etc may be used along with the word basin depending upon the size of the basin.

The term Lineament indicates any geographical or geological feature occurring in a line or in a linear fashion. But now a days the term lineament is used in such a fashion that it appears that lineament indicate only fracture zone, nothing else. Sometimes in same map or figure occurrences of lineaments (indicating fractures) and shear zones are shown separately though shear zone is also a lineament. The sand dunes occurring in coastal area, very often display linear fashion resulting a lineament and sand dunes definitely do not indicate any fracture zone.

Confusing nomenclatures are frequently used to describe different rock types of any area. The following type of statement is very often found in literatures now a days. “The most common rock types of the area are granites, gneiss, schist, and charnockites etc” The terms like gneiss and schist denote only the structural features of rocks and these terms may be used as only suffix, e.g Granite gneiss, Mica schist etc.

CONCLUSION: Ground water development plan for any area is formulated mainly based on availability of ground water resource in the area and for which precise estimation, as far as possible, of ground water resource is needed. Hence, such type of methodology is to be adopted which will lead to a correct assessment of resource as far as possible. Not only for resource estimation but also for monitoring of ground water regime both quantitatively and qualitatively and also for augmentation of ground resource such procedures and techniques may be adopted which will help to derive the maximum realistic situation.

DISCLAIMER : This is a compilation of the discussion and feedback received from people of various profession from agriculture to rocket scientists and I have merely contributed as a compiler. This article does not in any way reflect my personal opinion or the organization I work for.