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Nature of salt affected soils and poor quality waters in Rajasthan

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					Nature of salt affected soils and poor
    quality waters in Rajasthan




                  14
2. Nature of salt affected soils and poor quality waters in
                         Rajasthan.
         Rajasthan is the largest state of India comprising of 32 districts spread over 34.24
m ha. At present about 11.22 Lac hectares of land is affected by salinity and sodicity in
the state (Sharma, 1998). Considerable area of salt affected soils lies in Jaipur, Bhilwara,
Pali, Ajmer , Bharatpur, Bundi, Jodhpur, Kota and Sri Ganganagar districts. Further, all
western districts suffer due to this problem. The saline alkali soils in Rajasthan usually
occur in association with normal soils of arid and semi arid regions. The contributing
factors for the formation of these soils are low rainfall, high temperature and high
evaporation, presence of salts at some depth in the soil profile, use of poor quality
waters for irrigation in soils having low permeability, high water table and impeded
drainage. Excessive use of irrigation water and seepage from canals resulting into rise of
water table are also very important contributory factors in the development of saline-
alkali soils and water logging in canal command areas. The quality of under ground
irrigation water in majority of the areas in arid and semi arid regions is poor. The
problem of salt infestation due to use of saline waters for irrigation had covered sizeable
area in Jaipur district followed by Ajmer and Pali districts. Jodhpur, Churu, Bikaner, Sikar,
Barmer and Jaisalmer districts are also badly affected districts with this problem
particularly where under ground saline waters are being used for irrigation. The EC of
under ground waters of Jaisalmer, Barmer, Jodhpur, Pali and Nagaur districts varies
form 3.0-7.0, 2.9-9.0, 2.0-10.0, 2.9-7.4 and 3.0-8.4 dSm-1, respectively. Saline water
problem is more intensive in western Rajasthan (Mehta et.al., 1969).

        Soluble salts, which accumulate in saline - sodic soils, consist mainly of chlorides
and sulphate of calcium, magnesium and sodium. Usually carbonate, bicarbonate and
nitrate ions occur in smaller quantities. Boron also occasionally occurs in small
quantities. The nature and proportion of the accumulated salts in soil obviously depend
on the source of the salts and nature of soil itself. These salts affect the plant growth
either due to their presence in higher quantities or changes in the exchange complex of
the soil colloids or by indirect effect on soil microbes and plant root activities, or a

                                             15
combination of all these factors. Chemical analysis of some of the saline alkali soils of
Rajasthan is given in table 2.1.

Table 2.1: Chemical analysis of some saline - alkali soils of Rajasthan.
                                                                                       -1
 Depth             pH      EC                           Saturation extract analysis (mel )
                              -1
 (cm)                    (dSm )     Ca + Mg          Na          K        CO3 + HCO3         SO4      Cl
                                             WELL IRRIGATION
 Kaparda ( Jodhpur )
 0-15             8.8     5.0         8.9           39.0        0.3           9.0            19.3    20.0
 15-35            8.6     14.0        27.6          111.2       0.5           7.0            23.9    108.5
 35-50            9.0     18.0        33.7          147.0       0.5           4.0            32.3    145.0
 50-95            9.0     11.0        11.3          98.0        0.3           6.0            31.5    72.2
 95-115           9.0     12.0        6.6           112.0       0.3           5.0            47.0    86.5
 Asalpur (Jaipur)*
 0-26              8.7     3.5         2.5           29.0        --           2.5            6.5     22.5
 26-43             8.7     4.2         7.5           35.0        --           2.0            14.5    26.0
 43-84             8.8     3.4         6.0           44.0        --           2.0            12.0    36.0
 84-129            8.8     3.5         2.5           29.0        --           2.5            6.5     22.5
                                             CANAL IRRIGATION
 Digod (Kota)
 0-17              8.4     3.9        12.8           27.2       0.2           8.4            12.2     --
 17-65             8.8     2.6        7.4            22.1       0.1           19.4           6.2     19.0
 65-95             8.8     7.8        33.1           53.0       0.2           10.0           34.0    34.8
 95-165            8.2     6.4        31.6           30.0       0.2           17.8           33.0    33.6
 Suansars (Kota)
 0-15              8.1    10.0        26.5           70.0       0.2           7.6            42.0    49.4
 15-40             8.2    8.7         16.2           58.0       0.2           6.0            25.0    54.2
 40-68             8.5    7.0         14.9           53.0       0.1           10.2           22.0    33.4
 68-95             9.3    1.6         4.9            10.6       0.1           7.8            2.8     5.6
 95-105            9.5    2.6         1.9            22.1       0.2           11.4           6.6     9.0

                                             TANK IRRIGATION
 Negadiya (Bhilwara)
 0-20           8.1       25.0        28.0          220.0       0.1           5.6            164.0   85.0
 20-50          8.3       15.0        11.6          135.0       0.2           3.4            120.0   30.0
 50-85          8.6       8.0         7.2           78.0        0.2           3.2             64.0   14.2
 85-105         8.6       7.5         10.2          63.0        0.2           3.8             60.0   10.8
Source: Saline-Alkali Soils in Rajasthan, their nature, extent and management, Research Monograph-1,
        Department of Agriculture, Government of Rajasthan, Jaipur.*Vyas et al (1973)



        Gypsiferous soils are found in Jamsar, Lunkaransar, Soorsar, Dattor, Sallor
distributory and Khusar minor and Mohangarh etc. The soils are shallow, found in
                                                   16
intradunal flats at low-lying areas. A consolidated gypsiferous material either as a hard
stratum or in powder form is found in soil. The surface soils are generally coarse
textured but medium and fine textured soil may also appear in depressions. Most of the
deposits are excavated for gypsum and other purposes.

         The soil salinity and sodicity problems of Rajasthan are primarily due to irrigation
with poor quality water. The severity of the problems is further accentuated by the
aridity of the state. About 64.6 per cent of irrigated area (60.2 Lac ha) is covered by well
irrigation out of which about 6.15 Lac ha area is affected with the problems of salinity
and alkalinity. Saline and alkali soils under irrigation are highest in Jaipur, Bharatpur,
Bhilwara and Pali districts. The least affected districts in the state are Udaipur,
Dungarpur and Banswara (Table 2.2).

Table 2.2: Salt affected area under irrigation in different districts of                  Rajasthan


 Districts               Total irrigated**         Salt affected area under irrigation (`000 ha)*
                         area (2000-01)
                                             Canal         Tank       Wells    Inundation       Total

               1                2             3             4           5           6               7
 Ajmer                        85.24           --           1.64       50.06         --         51.70

 Alwar                        457.18         1.06           --        20.80         --         21.86

 Banswara                     49.61           --           0.16       0.40          --          0.56

 Barmer                       146.96          --            --        9.31          --              9.31

 Bharatpur & Dholpur          82.25          3.54          6.12       39.14        5.16        53.96

 Bhilwara                     115.78         0.10         12.04       91.00         --        103.14

 Bikaner                      162.07          --            --        0.05          --              0.05

               1                2             3             4           5           6               7
 Bundi                        196.65         35.12         1.02       16.53         --         52.67

 Chittorgarh                  100.78         0.24          0.86       51.21         --         52.31

                                              17
 Churu                           76.04           --          --        0.36            --     0.36

 Dungarpur                       14.45           --          --        0.05            --     0.05

 Sriganganagar&                 135.98           --          --        0.35            --     0.35
 Hanumangarh

 Jaipur & Dausa                 571.98           --         0.28     139.96            --   140.24

 Jaisalmer                       90.41           --          --        0.19            --     0.19

 Jalore                         199.28           --          --       36.42            --    36.42

 Jhalawar                       117.60           --          --        0.28            --     0.28

 Jhunjhunu                      243.56           --          --        0.59            --     0.59

 Jodhpur                        178.04           --          --       21.56            --    21.56

 Kota & Baran                   432.91         10.12        1.02      10.12            --    21.26

 Nagaur                         298.40           --          --       14.40            --    14.40

 Pali                           108.94          0.67         --      102.41            --   103.08

 Swai. Madhopur                 223.28           --          --        1.04            --     1.04

 Sikar                          261.52           --          --       12.60            --    12.60

 Sirohi                          44.87          0.12         --        5.16            --     5.28

 Tonk                           149.05           --          --        0.88            --     0.88

 Udaipur & Rajsamand             36.84           --          --        0.70            --     0.70

 Total                          6019.37        50.97       22.12     615.45        5.16     704.84
Source: * Mehta et al, (1969)    ** Deptt. of Statistics Govt of Rajasthan 2000-2001




                                                 18
       The salt affected soils in Rajasthan are found in small pockets throughout but
they are more dominant in South eastern part of Luni basin and in Ghaggar flood area.
In south eastern part of luni basin in Pali, Jalore, Barmer, Nagaur and Jodhpur district
about 0.60 mha of naturally saline soils are present. They are generally 50-80 cm deep
underlain by lime concretionary horizons. The saline lakes near Sambhar, Didwana and
Pachpedra are major source of salts. The salt affected soils in Luni basin generally occur
along the river course and in localized micro depressions (Kolarkar et al. 1980)

        The problem due to seepage of water under canal irrigation with consequent
rising of water table and development of salinity has affected vast areas in IGNP and
Chambal command belts in Kota, Bundi, Bharatpur, Chittorgarh and Pali districts.

         At present about 1.8 Lac ha land is affected by salinity and sodicity in IGNP
Command area. This area is increasing day by day due to extension of irrigation
facilities. Salt affected soils in IGNP are mainly located in three areas viz. Anupgarh
Branch, Suratgarh Branch and Eastern Block . Maximum area is located in Anupgarh
Branch due to bad soil physical properties viz. poor infiltration rate, high bulk density,
poorly developed structure, stratification, hard crust formation, tillage problem etc. The
soils are predominately clay to silty clay with medium sub angular blocky structure. They
are difficult to cultivate when dry and remain wet for longer time than normal soils and
are boggy when wet which leads to disruption and delaying in planting and harvesting
operation. EC varies from 0.50 to 55.0 dSm-1, pH 8.5 to 9.0 (in certain cases up to 9.8).
The flood plain soils of Ghaggar bed are invariably infested with salinity and alkalinity
problem. The sodic soils occur in patches and these are mainly found in Tal lands. After
introduction of the canal water in the IGNP, water-logging problem has developed. It
has been observed that on both North and South sides of Rajasthan Canal feeder, i.e.
Badopal, Dabli, Seelwala and Tibi areas, the water table is within two meters. In
between Rawatsar and Maseetawali head, the problem is mainly due to seepage of
canal water whereas in Lunkaransar lift canal area, the problem is of perched water
table. In part of Gaggar flood area, the problem has also developed due to water
stagnation in the depressions. In IGNP command stage II, out of total area (8.37 Lac ha)
surveyed, 44.5% area has hard pan within 10m depth from surface. If this area is
                                           19
brought into cultivation and excess irrigation is applied, it may also turn into saline one
and the problem of water-logging may come up. The status of development of water-
logging and salt affected area in Rajasthan and in IGNP are presented in Table 2.3 and
Table 2.4, respectively .Trend of water-logging in IGNP is presented in Table 2.5. During
1999 to 2003 the water-logged, critical and potential sensitive areas have shrunken
considerably in Stage-I. In Stage –II command the water-logged and critical area have
also reduced but there is an increase in potential sensitive area. This overall reduction in
the area is attributed to the lack of rainfall and poor availability of water in canal in last
three years.

Table 2.3: Water-logged and salt affected area in Rajasthan (' 000 ha)

                           Water –logged                                          Salt affected
                  Canal          Un –            Total           Canal       Out side      Coastal         Total
                command       classified                       command        canal
                                                                            command
 Rajasthan        179.5         168.8            348.3          138.2         983.8             Nil       1122.0
 India           2189.4        2338.1           4527.5         3469.1        3027.0        2069.1         8565.2
Source: Sharma (1998)

Table 2.4 : Area of salt affected soils in IGNP (ha)

                            Anupgarh Branch                   Suratgarh Branch                  Eastern Block
 Salt affected area       Area (ha)          % of        Area (ha)         % of         Area (ha)       % of total
                                                                                                          area
                                           total area                    total area
 Highly                    73850             27.2             19930        17.1          37230            23.7
 Moderately                34580             12.7             7830          6.7            --               --
 Total                    108430             39.9             27760        23.8          37230            23.7
Source :UNDP,F.A.O.(1971)




Table 2.5 Waterlogged area in IGNP command


                                                         20
 S                                                                  Total area (ha)
 No   Type of Area            Stage
                                      96– 97   97-98        98-99   99-2K    2k-01    01-02   02-03   03-04


 1.   Potentially sensitive     I     297820 310056 298760 280023 225153 179170 164375 195000
      area (water table        II              17303        18067   19666    12184    18304   24572
      within 1.5 to 6.0 m )                                                                           13481
 2.   Critical area (water      I     24140    28760        27960   26430    13425    11355   8750    9259
      table within 1.0 to
      1.5 m)                   II              3610         3792    5088     2229     1261    453     317

 3.   Water logged area         I     17220    22008        19492   18150    12672    10098   5755    2531
      (water table within
      0.0 to 1.0 m)            II              1243         1243    1466     369      78      16      04


        Source: CAD Commissioner IGNP, Bikaner 2003-04
      Sharma et al. (1968) observed that in canal irrigated area of Pali district problem of
soil had developed due to higher water table , whereas, in well irrigated areas the
problem of salinity and alkalinity is due to use of saline under ground water.

        High water table with soil salinity and sodicity is also a common problem of
irrigated areas of Chambal command in Rajasthan. Out of total area surveyed in
Chambal command, 16192 ha area was salt affected (table 2.6). The rise in water table
was attributed to canal seepage and over irrigation. Generally the shallow ground
waters have EC values > 1.5 dSm-1 with recorded values as high as 20 to 50 dSm-1
(Anonymous, 1974). The soils of the command area are fine textured consisting of tough
clay, which are slowly permeable, calcareous and highly expanding. These soils occur in
nearly level to gentle sloping (0.08%) land. Top soil of Kota series are 1.2-2.5 m deep
with high clay content and very slow permeability.




                                                       21
Table 2. 6: Distribution of salt affected area (ha) in Chambal command

 S.No.    Saline/ Sodic Soil                             Area ( ha)         (%)Area

                               -1
 1.       Saline EC >4 dSm                                 5652              9.52

                                    -1
 2        Saline Sodic EC >4 dSm & SAR >15                 8415              14.18

                           -1
 3        Sodic EC <4 dSm & SAR >15                        2125              3.58

          Total Salt Affected Soils                       16192              27.28

Source : Anonymous (1974).

       Lal et al. (1971) reported that in Jobner tract there was no salinity problem but
these soils had alkalinity problem. Mali (1971) observed that in Boraj- Mehla tract
ground water fell in three classes C4S4, C3S2 and C2S1. The saline nature of under ground
water, high water table, impermeable hard kankar pan, low tophographical situation,
salt deposits in vicinity of the areas and aridity of the tract, were traced out to be the
most important factors responsible for development of salt affected soils in the area.

        Jat (1972) observed that principal caused for origin of salt affected soil in Nava
tract (Jaipur) appeared to be saline nature of underground water, high water table, low
topographical situation and salt deposits in vicinity of the tract.

       Mathur et al. (1968) reported that Rajasthan has wide spread problem of salinity
and alkalinity of soils which was mainly located in districts of Jodhpur, Pali, Bhilwara,
Ajmer, Jaipur, Bharatpur, Alwar, Chittorgarh, Jalore, Nagaur and Sirohi constituting
about 15.0 per cent of cultivated area.

        Dhir et al. (1979) found that in Pali block of Rajasthan the salinity was high to
very high in 25% area of the block. Studies on genesis and taxonomy of wide spread
saline and sodic soils in Bharatpur district revealed that clay migration was responsible
for formation of argilic and natric horizones in three pedons classified as Typic
Haplustalf, typic Natrustalf and Aquic Natrustalf, based on sub surface diagnostic
horizones and soil moisture regimes, as influenced by micro topographical positions.
                                             22
Two pedones were classified as Aeric Halaquept and typic Salorthid (Qureshi et. al. ,
1994). Kameria (1995) reported that sub surface soils of Zone IIa ( Transitional plain of
inland drainage) of Rajasthan have five salinity and alkalinity classes (i.e. S 1, S2, S3,S4 and
S5) Panwar (1996) classified the soils of Jobner tract in order – Entisol sub-order-
Natripsamments, further these soils have been grouped in Ustinatripsamments – great
group.

        Sikarwar (1997) reported that most of the soil of Bharatpur tehsil were alkaline
and highly saline in nature. Ram (1998) found that most of the irrigated soils of Pali tract
were alkaline and highly saline in nature while unirrigated soil of the tract were slightly
alkaline and moderately saline in nature. Singh (1994) observed that SAR & RSC of
underground water of Chirwa panchyat samiti ranged between 2.84 to 17.2 and 0.1 to
6.0 mel-1, respectively and these waters were characterized in to C4S4, C4S3, C3S3, C3S2,
C3S1, C2S1 and C2S2, classes.

       In command area of North- West Rajasthan, waterlogging and soil salinity has
been emerging as a serious problem covering 0.36 m ha land (Deo and Yadav,1999).
The lower available water capacities (6.0-14.4 cm m-1) and higher infiltration rate (10.9-
13.5 cm hr-1) of most of the soils of the region caused perched water. Soils are saline
sodic and were loaded with chlorides and sulphates of sodium. The underground water
was found Na- Mg-Ca types with dominance of chlorides followed by bicarbonates.

        Oswal (1999) reported that Sambhar Panchayat Samiti of Jaipur had moderate
salinity and slight alkalinity problem. The soils of Bhilwara, by an image interpretation
coupled with field studies was Taxonomically classified at family level in order Inceptisol
and Entisol. Of total area of 129501 ha , soils are distributed as 11384, 27677 and
55587 ha Saline, sodic and saline-sodic , respectively ( Sharma and Totawat, 2000).




                                              23
Waters from different sources and their Properties:

         The general properties of water include pH, presence of salts, their chemistry
(nature of dissolved salts), organic matter, seeds, spores, bacteria and other micro-
organisms. The properties differ from water of one source to another depending upon
the origin. Rain water has been considered to be of the most fresh quality although its
fertility is poor. River and canal water are usually fresh and sometimes alkaline but are
very conducive from the fertility point of view. Ground water may be either good or
alkaline /or saline.

Rain water:
        Chemical composition of the rain water from five places in Rajasthan located at
different precipitation isohytes and having different types of soils and environmental
conditions, is reported in Table 2.7. The pH of rain water varied from 7.2 to 8.3,
whereas, normal water in the atmosphere is in equilibrium with CO2 and has a pH of 5.7.
The total soluble salt concentration varied from 37.4 to 143.7 mgl-1. Among anions,
chlorides dominated over sulphates. The occurrence of saline water irrigated soils and a
large number of dyeing industries at Pali seem to be the causative factors for the
presence of excessive Na and Cl ions in the rain water over Pali (Agarwal, 1986).

Table 2.7: Chemical composition of rain water (1975-1977) over
             Rajasthan
                                                                             -1
 Location          pH    EC                         Ionic composition (mgl )
                                 -1    -        -         –2        +    +             ++     ++
                         (Scm )      Cl     NO3    SO4        Na       K         Ca        Mg

 Palsana (Sikar)   7.8   83.3         4.5    0.83   1.12       4.8      5.4       11.3      1.97

 Pali              8.3   143.7        27.1   1.15   0.83       28.8     2.4       12.7      1.87

 Jodhpur           7.5   37.4         9.5    0.56   0.87       3.3      1.1       5.4       1.00

 Bikaner           7.8   38.6         12.2   0.85   0.75       7.5      4.5       5.2       1.18

 Jaisalmer         7.2   71.9         6.4    3.06   1.56       7.5      10.3      12.1      1.10

Source: Agarwal (1986)

                                               24
Canal water:
       Darra et. al. (1964) reported that canal waters in Rajasthan are of good quality
.The average water has a pH and EC of 7.8 and 0.4 dSm -1, respectively. SAR and RSC
were around 6.0 and 1.36 mel-1, respectively. In Rajasthan, the canal waters of
Chambal, Jawai, Bagolia, west Banas and IGNP are suitable for agricultural use. The
water of Ora dam is, however, highly saline primarily because of main nalah feeding the
dam flow through a saline patch (Mehta et.al., 1969). According to UNDP reports (1970)
waters of IGNP command had average value of pH 7.8 , EC 0.2 dSm-1, respectively, SAR
and RSC were around 1.02 and 1.36 mel-1, respectively.

Lakes:
        In Rajasthan, there are many important salt lakes, for example, Sambhar,
Didwana, Pachbhadra and Phalodi which contribute to more than 25 per cent of the
total salt ouput of India. The overall salinity of the lake waters is by far the highest on
the earth qualifying them to be called as brine. The chemical composition of the brines
collected from the four salt lakes is presented in Table 2.8.

Table: 2.8: Chemical analysis of brines of different salt lakes of Rajasthan

 Constituents *                                            Locations
                    Sambhar                 Didwana               Pachbhadra          Phalodi
 pH                 8.28                    8.9                   7.26                7.23
   -
 Cl                 119535 (12)**           166725 (17)           143183 (14)         130225 (13)
        -
 SO4                22854 (2.3)             54910 (5.5)           14108 (1.4)         12258 (1.2)
           -
 HCO3               3586                    2639                  267                 60.5
        --
 CO3                3705                    628                   Nil                 Nil
       -
 NO2                1319                    0.05                  9.85                0.90
       -
 NO3                3.33                    1.05                  32.68               1.6
     ++
 Ca                 Nil                     23.2                  63.6                950
      ++
 Mg                 Nil                     85.5                  12219               990
  +
 K                  461                     580                   3289                939
       +
 NH4                Nil                     3.5                   0.16                n.d.
 B                  70.2                    171.5                 24                  5.1
 TDS                282349 (28.23)          371098 (37.11)        301543 (30.15)      240308 (24.03)
                                                                                     -1
Source: Chaudhury et al. (1966) * All the constituents except pH are expressed as mgl
** Figures in parentheses express weight in g per 100 cc of brine.


                                                   25
Tanks:
       The quality of tank waters irrigating a large acreage in Ajmer, Bhilwara, Jaipur,
Alwar and Bharatpur districts is invariably normal for the crop cultivation (Mehta et al.,
1969)
Ground water:
        The ground water in the arid zone of Rajasthan, the Great Indian Desert, occurs
in rocks ranging in age from the Precambrian to the quaternary system. In hard
crystalline rocks, such as gneisses, schist, phyllites and quartzite, the ground water
occurs and moves through the joints, fractures, foliation planes and weathered zones,
whereas in sedimentary rocks, like sandstone, the ground water occurs and moves
through the pore-spaces and interstitial openings of granular sediments.
        Ground water in western Rajasthan generally occurs under water-table
conditions (unconfined) in hard crystalline and alluvial formations. In sandstone of
tertiary and older ages, ground water also occurs under semi-confined to confined
conditions owing to the presence of overlying impermeable horizons. The depth to
which water is available in the arid zone ranges from less than 10 m to as high as 140 m
below the land surface. The deepest water table has been observed in the area south of
Bikaner in Rajasthan.
        The ground water department of Rajasthan has carried out a very systematic
survey of the quality of ground waters in Rajasthan. Percentage distribution of ground
waters based on about 10,000 samples, with respect to salinity in various districts shows
that as rainfall increases from the arid districts of western Rajasthan to the semi arid
districts in eastern Rajasthan, the average quality of ground water improves. In arid-
cum-semi-arid districts the percentage of saline water          (EC>5 dSm-1) is appreciably
high, varying from 30-50 per cent in nine districts, namely, Barmer, Bikaner, Churu,
Ganganagar, Jaisalmer, Jalore, Jodhpur, Nagaur and Pali. EC of some ground waters is 10
to 15 or even higher than 15 dSm-1. The highest EC of 49, 35, 34 and 22 dSm-1 have been
recorded in ground waters of Bikaner, Ganganagar, Barmer and Jaisalmer districts
(Gopal and Bhargava, 1981). The percentage of such waters in Jhunjhunu and Sikar
districts is relatively low. In the seven semi-arid districts, EC is generally less than 10
dSm–1, except Bharatpur district where ground waters are of as poor a quality as in the
arid districts. The percentage of saline ground waters varies from less than 5 to 15. In
                                            26
mid districts, the percentage of saline waters is negligible except in the Bundi district. In
sub-humid districts, EC is largely less than 2.2 dSm-1 except in Kota. Ground water
department of Rajasthan has prepared a map showing quality of waters in Rajasthan.
The                                                                                     map
is




presented in Fig 4.




                                             27
                   Fig. 4 : Quality of underground waters of Rajasthan
        The classification of the ground waters of Rajasthan in three groups, namely, (a)
arid and arid-cum-semi-arid districts; (b) semi-arid districts; and (c) humid and sub-
humid districts, and their distribution in different salinity classes, brings out a very
interesting picture. About 90 per cent of the ground waters in the western arid districts
have EC less than 10 dSm-1, whereas in the semi-arid and humid districts 90 per cent
waters have EC less than 5 and 2.2 dSm-1, respectively (Table2.9).
Table 2.9: Percentage distribution of ground waters of Rajasthan in different salinity
                classes
                                                                 -1
 District       No. of                                    EC (dSm )
                samples   <0.75   0.75 – 2        2.2 – 5       5 – 10     10 – 15   >15
                (10329)
 Arid
 Barmer            322      10        11              31              27        15    7
 Bikaner           137       2        27              37              21        10    3
 Ganganagar        361       7        36              23              20        10    4
 Jaiselmer         295      19        37              20              20        4     1
 Jodhpur           357       8        38              27              16        8     4
 Arid-cum semi-arid
 Churu             244       3        16              30              29        15    7
 Jalore            505      10        28              30              20        10    3
 Jhunjhunu         363       8        47              34              11
                                             28
 Nagaur            459     8          36         28                22         4         3
 Pali              498    12          34         20                17         9         8
 Sikar             174    12          55         28                5          -         -
 Semi-arid
 Ajmer             388    15          52         26                7           -        -
 Alwar             764    23          60         14                3           -        -
 Bharatpur         499    20          31         19                14         16        -
 Bhilwara          572    18          52         20                10          -        -
 Jaipur            939    30          45         18                7           -        -
 S.Madhopur        505    26          52         16                6           -        -
 Tonk              333    10          50         26                14          -        -
 Sub-humid
 Chittorgarh       442    35          61         4                 1          -         -
 Bundi             238    38          43         17                -          -         -
 Udaipur           640    23          64         10                2          -         -
 Sirohi             94    55          37         17                -          -         -
 Humid
 Banswara          296    73          26         1                 -          -         -
 Dungarpur         189    55          41         3                 -          -         -
 Jhalawar          243    60          34         6                 -          -         -
 Kota              472    30          57         12                1          -         -
Source: Gupta (1979).

        SAR value of ground waters in some districts of Rajasthan has been shown in
Table 2.10 .It is apparent that values as high as 96 or 114 are noted in the waters of
Nagaur and Jodhpur districts. The ground waters of arid districts have relatively higher
values than the semi-arid districts. Sodium Adsorption ratio of ground waters in western
Rajasthan are usually greater than 20, in eastern Rajasthan SAR values rarely exceed 20.
For example, in Alwar district, the percentages of ground waters having values of SAR
less than 10, 10-20 and greater than 20, are 76, 21 and 3 respectively. Distribution of
underground water according to EC and SAR is presented in Table 2.11.

Table 2.10 : SAR values of ground water in Rajasthan

 District                 No. of samples                                SAR
                                                       Range                  Average
 Arid
 Barmer                        290                    1.2 – 32.4                   --
 Bikaner                       137                    0.6 – 56.1                   --

                                           29
 Ganganagar                   200                 1.1 – 36.0                 --
 Jaisalmer                    318                 1.4 – 26.8                 --
 Jalore                       50                  12.0 – 53.6               24.7
 Jhunjhunu                    9                   12.5 – 19.6               33.5
 Jodhpur                      74                  3.7 – 113.6                --
 Nagaur                       74                  15.8 – 95.7               31.7
 Pali                         84                  3.8 – 63.8                21.9
 Sikar                        14                  3.6 – 17.2                 --
 Semi-arid
 Ajmer                        19                  3.3 – 69.5                 --
 Alwar                        340                 0.2 – 61.5                 --
 Bharatpur                    10                  2.8 – 77.8                 --
 Bhilwara                     118                 4.1 – 73.3                23.3
 Jaipur                       92                  4.8 – 39.9                16.1
 Sub-humid
 Udaipur                      166                 1.8 – 18.9                6.4
Source: Gupta (1979).




Table 2.11: Percentage-wise distribution of ground waters of western       Rajasthan in
               different EC and SAR classes

           -1
 EC (dSm )          No. of                            SAR
                   samples    <10       10 – 18        18 – 26   26 – 34           >34
                    (2278)
 <0.25                  3     66.7       33.3             --       --               --
 0.25 0.75              167   93.4        5.4            1.2       --               --
 0.75 – 2.25            607   72.8       21.9            3.6       1.8             0.3
 2.25 – 5.0             659   31.0       39.4           22.3       4.7             2.6
 5 – 10                 496   6.6        28.4           31.9      21.2             11.7
 10 – 15                225   2.2        12.5           30.7      33.3             21.3

                                        30
 >15                   121      3.3           4.1           12.4        22.3       57.9
Source: Dhir (1977).

        The tube well waters of Jodhpur and Pali districts were reported to be very high
in EC, SAR and chloride content ( Shankaranaryan et al.,1965), while those from B

        Bhilwara, Ajmer and Bharatpur districts were found to be moderate to highly
dominated by the sodium salts ( Mathur et al.,1968). Tube-well waters of Nagaur district
were classified as highly saline having sodium as the dominant cation (Paliwal and
Gandhi, 1967). The tube-well waters of Sriganganagar, Bikaner, Churu, Jalore, Nagaur,
Jaisalmer and Jodhpur have high salinity and low to medium sodium hazard ( Puntamkar
et al.,1967; Raghava and Joshi, 1967).

        In the ground saline waters of western Rajasthan, the incidence of occurrence of
RSC is less. The percentage of waters having RSC>2.5 mel-1 was 0, 14, 4, 0 and 20 in
districts of Barmer, Jaisalmer, Jalore, Jodhpur and Pali, respectively (Mehta et al., 1970).
In Nagaur district, RSC in ground waters varied from 0 to 21.5 mel-1, with an average
value of 4.1 mel-1 (Paliwal and Gandhi, 1977). In Ajmer, Jhunjhunu and Sikar districts,
RSC was generally less than 10 mel-1 (Singh and Mahnot, 1976). In high rainfall districts
namely, Bundi and Jhalawar more than 75 pr cent ground waters have RSC less than 2
mel-1 (Gupta et. al., 1974; 1975).

       Sodium dominates invariably in all the waters followed by magnesium and
calcium. The percentage of sodium ions varies from 60 to 80 of the total cation
concentration. The ratio of magnesium to calcium varies from 1 to 5. Amongst anions,
chlorides dominated in all the districts except in Ajmer where sulphates dominated. The
second anion was generally bicarbonate in well waters of such districts as had an
average EC between 2 and 3 dSm –1. In the remaining districts sulphate was the
dominant anion and such districts had an average EC >4 dSm-1 (Table 2.12).

Table 2.12: Mean chemical composition of ground waters in some                  districts of
              Rajasthan


                                            31
                                                                                  -1
 District       No. of      pH     EC                                 Ions (mel )
                Samples                   -1
                                   (dSm )
                                               Na      K     Ca     Mg       Cl        SO4     CO3    HCO3

 Ajmer              19       8.7    5.5        37.7   0.28   4.86   5.50    10.2       24.76   0.80   9.70

 Alwar              334      8.2    2.4        14.9    -     3.57   6.85    12.2       8.82    2.85   8.42

 Barmer             339      7.9    5.2        38.8   1.60   4.73   7.13    38.        6.18     -     6.40

 Bharatpur          276      8.3    3.1        20.2    -     3.70   8.70    16.5       8.20    0.50   8.40

 Bhilwara           235      8.1    5.5        39.6   0.84   5.05   5.34    42.0       11.43   0.40   8.35

 Bikaner            249      7.8    6.3        45.5   0.98   8.10   9.20    46.2       12.20    -     6.90

 Jaipur             161      8.3    3.0        35.1   0.32   3.61   11.40   29.7       11.10   3.74   8.34

 Jaiselmer          318      7.7    5.0        33.4   0.72   5.42   4.74    30.6       7.16    0.86   6.55

 Jalore             472      8.0    3.3        34.8   1.01   4.96   6.19    33.2       5.50     -     6.91

 Jodhpur &          943      8.0    5.5        38.8   1.24   4.20   8.35    36.7       8.67     -     9.73
 Nagaur

 Pali               573      8.0    5.1        39.2    -     5.49   6.64    22.7       10.85   1.12   8.21

 Sirohi             28       7.6    2.9        23.5    -     4.62   2.49    19.5       3.39    2.00   8.15

 Ganga nagar*       138      7.6    4.3        18.7   0.6    8.8    10.1    20.5         -     1.1    5.0

 Hanumangarh*       72       7.7    2.8        10.7   0.9    3.7    7.6     11.6         -     1.1    6.2

Source: Paliwal (1972, 1978) *Yadav et al.( 1998)




       On an average, potassium ion was either absent or occurred in amounts less than
          -1
2 mel . Likewise, amongst anions, carbonates contributed the least and did not exceed
4 mel-1. Thus, in general well waters of Rajasthan could be characterized as Na-Mg-Ca
cation type and Cl-HCO3-SO4 anion type in the low salinity class (EC <3 dSm-1) and Cl-
SO4-HCO3 anion type in the higher salinity class (EC>5 dSm-1). As EC of water increases
from low to high, percentage of divalent cations decreases (Table2.13).A large number of
waters which contain Ca+Mg more than 50 per cent have EC less than 2.25 dSm -1 and
waters with EC greater than 4 dSm-1 usually contain less than 30 per cent Ca+Mg (Table
2.13)


                                                      32
Table 2.13: Percentage-wise distribution of ground waters of some districts of western
                Rajasthan on the basis of conductivity and divalent cation percentage

 EC                                                 Divalent cation percentage
           -1
 (dSm )                     (>50)                                (30 – 50)                                (<30)
                Jaisalmer   Bikaner      Barmer   Jaisalmer       Bikaner    Barmer           Jaisalmer   Bikaner        Barmer


 <0.25            0.8         -            -         -               -             -              -          -             -
 0.25– 0.75       7.6        0.8          0.9       1.2             0.8           1.3            0.8         -            0.4
 0.75– 2.25       18.9       6.4         11.1       4.2            12.0           7.0            6.4        6.3           6.6
 2.25 – 4.0       1.6        2.8          6.6       5.4             8.2           4.8            7.4       11.5           7.4
 4.0-6.0          2.0        2.0          2.2       2.4             0.8           7.1           12.0        6.2           11.5
 6.0-12.0         2.4        3.2          1.8       6.4             5.0           4.1           13.6       17.0           18.2
 >12.0            0.8        0.4          0.4       2.0             3.8           0.4            4.0       13.0           8.2
Source: Bhandari et al.,(1971)

       Percentage-wise distribution of ions with respect to different salinity classes
(Table2.14) shows that with an increase in salinity the proportion of sodium and
chloride ions increases whereas, calcium, magnesium and carbonate plus bicarbonate
decreases. However, the proportion of sulphate ions increases regularly up to a mean
value of 8 dSm-1 and then decreases in highly saline waters (Paliwal, 1972). The quality
of ground water varies with soil type but it is difficult to correlate them ( Darra et. al.,
1964).

Table2.14: Percentage-wise distribution of ions in relation with EC in groundwater of
              Rajasthan
                                                                             -1
 Ions                                                               EC(dSm )

                                   <2                     2–6                          6 – 10                     >10
      +
 Na                               51.9                    70.3                          72.2                      74.1
  +
 K                                 1.5                    3.2                           2.3                       1.6
      ++
 Ca                               20.4                    9.4                            .9                       9.2
      ++
 Mg                               26.2                    17.1                          16.6                      15.1


                                                          33
  -
 Cl                      30.3              54.1              67.2              75.3
    =
 SO4                     10.3              15.3              20.4              15.2
        - =
 HCO3 +CO3               59.3              30.6              12.4              9.5
 No. of samples          1671             1372               545               344
 Percentage               42               35                14                 9

Source: Paliwal (1972)

        The tube-well waters from Bhilwara district of Rajasthan revealed that waters
high in bicarbonate were associated with low total salt concentration and bicarbonate
constituted as high as 60 per cent of total anions. The EC of waters having RSC more
than 2.5 mel-1 mostly ranged between 1 to 2.5 dSm-1 ( Ram Deo, 1978).

        Studies conducted by Gupta (1991) revealed that ground waters are sodic in
character due to high SAR or RSC values. The SAR ranges from 0.15 to 176.8 with an
average value of 13.9. In Barmer, Bikaner and Jaisalmer districts more than 33.3 per
cent waters have SAR more than 18.High RSC generally occurs in low to medium salinity
waters and ranges form nil to 68.8 mel-1 with an average value of 3.1 mel-1. The districts
viz. Jhunjhunu (42.5%), Nagaur (32.3%) and Sikar (30.2%) have high RSC (more than 5
mel-1) in ground water.

        Lot of work has been done under the aegis of AICRP on management of salt
affected soils and use of saline water on quality of underground water of Jaipur, non-
command area of Bikaner, Churu and part of Nagaur districts. In Bikaner, Churu and part
of Nagaur districts from last decade only the farmers are installing tubewells in their
fields and have started irrigated agriculture. Thus the quality of underground waters
which had been quoted by earlier workers was related to the water (wells) which were
dug by PHED and used for human consumption and not for agricultural purposes. Work
on ground water quality done under the above mentioned project is highlighted below.

Jaipur District :
      Twelve tehsils of Jaipur district viz. Kotputali, Viratnagar, Amber, Jaipur,
Sanganer, Bassi, Dudu, Phagi, Chaksu, Sambhar, Jamva Ramgarh and Dausa were
                                           34
surveyed to know the underground water quality. Vyas et.al. (1993) reported that in
underground water of Jaipur district the pH ranged between 7.0 to 9.0. EC of 79.5
percent samples was less than 4 dSm-1 and of 62.5 percent samples it was even < 2.0
dSm-1. In case of Bassi, Dausa, Dudu, Phagi and Sambhar tehsils, more than 10 percent
samples had EC>6 dSm-1. Except Sanganer, Bassi and Sambhar tehsils, more than 54
percent samples had RSC < 2.5 mel-1 and about 7.5 to 27.1 percent samples had RSC
between 2.5 to 5.0 mel-1. Sanganer and Sambhar tehsils had more than 40 percent
samples having RSC > 5.0 mel-1. On an average 57.8, 19.5, 15.0 and 7.5 percent of total
samples had RSC < 2.5, 2.5-5.0, 5.0-10.0 and > 10.0 mel-1, respectively. In Kotputali,
Viratnagar, Amber, Jamva Ramgarh and Jaipur tehsils more than 80 percent samples had
SAR value of < 10. Whereas, in Sanganer, Phagi, Chaksu, Sambhar and Dausa tehsils 34.4
to 41.5 percent samples had SAR between 10 to 20. In Sambhar and Dudu tehsils more
than 30 percent samples had SAR>20. Range of chemical characteristics of
tubewells/open well waters and distribution percentage of samples of different tehsils
of Jaipur District falling into different ranges of pH, EC, RSC & SAR are given in Table 2.15
and 2.16, respectively.

Table 2.15: Range of chemical characteristics of Tubewells/Open well waters of
              various tehsils of Jaipur District

 Chemical                                          Tehsils
 Characteristics
                   Kotputali   Viratnagar    Amber      Jaipur (107)   Sanganer     Bassi
                     (53)*        (70)        (207)                      (53)       (59)




                                             35
 pH                                      7.0-9.0          7.3-8.8      7.2-9.0            7.1-8.2      7.0-8.7               7.3-8.8
                  -1
 EC (dSm )                               0.6-7.0          0.9-7.0      0.4-2.9            0.5-6.1      0.6-6.5              0.5-21.5
      ++               -1
 Ca            (mel )               2.4-22.2**          1.4-22.6**     0.2-4.0            0.2-0.6     0.6-15.6**            0.8-71.4**
          ++           -1
 Mg (mel )                                  --               --       0.0-10.0            0.4-15.7          --                 --
      +                -1
 Na            (mel )                 1.0-47.2           1.0-46.0     1.0-24.0            1.0-41.0     1.0-54.2             1.0-140.0
  +                -1
 K             (mel )                    0.1-2.0          0.1-0.5            --           0.01-1.0     0.1-0.5                 --
    -2    -1
 CO3 +HCO3                            4.0-16.0           4.0-18.0     1.8-10.0            1.6-16.0     3.2-27.0             3.3-20.6
     -1
 (mel )
     -1                -1
 Cl            (mel )                 0.8-52.2           0.8-47.0     0.0-156.0           0.8-46.2     1.0-46.6             1.0-182.4
                   -1
 RSC (mel )                           Nil-12.4            Nil-11.0     Nil-11.9           Nil-18.2     Nil-19.2             Nil-20.6
 SAR                                  0.7-19.8           0.6-15.2     0.6-21.9            0.4-30.8     0.6-25.5             0.6-26.1

                                    Dudu (209)             Phagi      Chaksu        Sambhar (162)     J. Ramgarh            Dausa
                                                            (59)       (61)                               (48)               (53)
 pH                                      7.1-8.9          7.2-8.9      7.3-8.7            7.0-8.4      7.4-8.8               7.0-8.8
                  -1
 EC (dSm )                            0.5-17.6           0.7-12.0      0.6-8.2            0.6-41.6     0.4-2.3              0.6-10.0
      ++               -1
 Ca            (mel )                    0.2-0.3        2.2-69.6**   1.6-57.6**          0.5-21.5**   3.0-11.1**            tr-35.0**
          ++           -1
 Mg (mel )                            1.5-68.4               --              --           6.0-57.0          --                 --
      +                -1
 Na            (mel )                1.6-156.0           2.0-84.5     2.5-46.6           3.0-260.0     1.2-72.0             3.5-102.2
  +                -1
 K             (mel )                       --           0.1-0.40            --              --             --                 --
          -2                -1
 CO3 +HCO3                               tr-43.0         4.9-26.4     3.4-17.4            4.0-40.0     2.5-17.5             2.2-20.6
           -1
 (mel )
     -1                -1
 Cl            (mel )                1.0-158.5           1.0-120.6    2.2-53.0           1.0-235.0     1.5-66.0             2.0-118.0
                   -1
 RSC (mel )                           Nil-20.6            Nil-19.4     Nil-12.1           Nil-36.5     Nil-12.4             Nil-19.6
 SAR                                  1.1-97.8           1.2-29.3     1.3-18.3            1.5-52.0     0.6-16.8             2.0-41.8
Source : Vyas et al. (1993)                          * Number of samples tested ** Figures are of Ca + Mg

Table 2.16 : Distribution (percent) of water samples of different tehsils of Jaipur
             District falling into different ranges of pH, EC, RSC and SAR
                                                                                                                 -1
 Tehsils                                             pH range                                    EC range (mel )
                                 7.0 -7.5          7.5 -    8.0 -    > 8.5        <2         2-4      4-6       6-8             >8
                                                   8.0      8.5
 Kotputali                         1.9             13.2     56.6     28.3         64.2       22.6     7.5             5.7           --

                                                                        36
 Viratnagar       2.9          28.4      57.2    11.4   91.4     7.1         --       1.4    --
 Amber            6.8          20.3      28.5    44.4   96.6     3.4         --        --    --
 Jaipur           22.4         59.8      16.9    0.9    88.8     2.8        7.5       0.9    --
 Sanganer         3.8          52.8      33.9    9.4    69.8     24.5       3.8       1.9    --
 Bassi            13.6         30.2      32.2    23.9   61.0     20.0       13.6      1.9   3.4
 Dudu             9.6          43.5      37.8    9.1    14.5     24.6       26.6     14.5   19.7
 Phagi            11.9         62.7      20.3    5.1    39.7     36.2       13.8      5.2   5.2
 Chaksu           14.8         49.2      32.8    3.3    52.5     37.7       6.6       1.6   1.6
 Sambhar          34.6         48.8      16.6     --    29.6     30.8       15.4     10.5   13.7
 Jamva            4.2          22.9      66.6    6.3    91.7     6.3        2.0        --    --
 Ramgarh          17.0         34.0      41.5    7.5    62.2     17.0       11.3      5.7   3.8
 Dausa
 Average          12.1         37.6      35.6    14.7   62.5     17.0        10.0     4.9    5.6
                                      -1
 Tehsils                      RSC (mel ) range                           SAR range
                  < 2.5         2.5 -      5-    > 10     < 10          10 - 20   20 - 30   > 30
                                5.0        10
 Kotputali         60.4         20.8      13.2   5.7      79.2           20.8       --       --
 Viratnagar        67.1         21.4      10.0   1.4      90.0           8.6       1.4       --
 Amber             66.2         22.2      11.0   1.9      91.3           7.7       1.0       --
 Jaipur            57.0         27.1      14.0   1.9      82.6           11.6      2.9      2.0
 Sanganer          30.2         7.5       24.5   37.7     54.7           41.5      3.8       --
 Bassi             45.8         17.0      27.1   10.1     67.8           28.8      3.4       --
 Dudu              64.3         13.9      16.9   4.8      27.8           28.8      20.0     23.4
 Phagi             57.6         22.0      13.6   6.8      52.5           39.0      8.5       --
 Chaksu            62.3         18.0      18.0   1.6      65.6           34.4       --       --
 Sambhar           37.7         18.2      22.0   22.0     37.1           34.6      17.0     13.3
 Jamva             58.3         25.0      10.4   6.3      83.3           14.6       --      2.1
 Ramgarh           54.7         15.1      17.0   13.2     37.7           41.5      13.2     7.6
 Dausa
   Average         57.8         19.5     15.0    7.7      62.9           23.8       7.2     6.1
Source : Vyas et al. (1993)

        On an average 35.5 percent water samples had none of the problem and hence,
were of good quality. The range of good quality water in different tehsils, however ,
varies from 7.4 per cent in Sambher to 65.2 percent in Amber tehsil. In Viratnagar,
Amber, Jamva Ramgarh and Jaipur tehsils, percentage of good quality water was above
50. In Kotputali and Chaksu it was about 37.7 percent and it was low in Bassi, Sanganer,
Phagi and Dudu tehsils and was lowest in Sambhar tehsil (Table2.17).



                                                   37
        In general there was less problem of salinity and sodicity alone. The results
showed that there was problem of RSC, which was as high as 69.8 percent in water
samples of Sanganer followed by Sambhar (58.0%) and Bassi (54.2%) tehsils. In other
tehsils it was in the narrow range of 33 to 42 percent. There was both salinity and
sodicity problem in Dudu tehsil (42.6%) (Table 2.17 ).

       There was a severe problem (> 50%) of soil alkalinity in Viratnagar (72.9%) and
Phagi (64.9%) tehsils, moderate (25 to 50%) problem in Sambhar (46.7%), Jaipur
(36.1%), Dudu (36.0%) and Chaksu (32.8%) tehsils and slight problem in Bassi (23.7%),
Amber (20.3%), Dausa (18.7%), Kotputali (11.3%) and Jamva Ramgarh (10.4%) tehsils.
Severe problem of soil salinity was observed in Phagi (61.4%) tehsil while it was
moderate in Dudu (32.6%) tehsil and slight in Tehsils of Chaksu (24.6%), Sambhar
(16.6%), Bassi (15.3%) and Dausa (14.6%). (Table 2.18)

Table 2.17: Classification of irrigation waters of different tehsils of Jaipur District

                     Kotputali   Virat nagar       Amber                Jaipur          Sanganer    Bassi
 Water quality
                      (53)**        (70)               (207)             (107)            (53)      (59)

 Good                  37.7         61.4               65.2              52.3             22.6      30.5

 Marginally saline     9.4          4.3                0.5               0.0              1.0       1.7

 Saline                3.8          0.0                0.0               0.0              0.0       3.4

 Saline sodic          9.4          1.4                0.5               4.7              5.7       10.2

 E1 RSC water          13.2         27.1               26.1              33.6             30.2      32.2

 E2 RSC water          26.4         5.7                7.7               9.3              39.6      22.0

                     Dudu        Phagi         Chaksu          Sambhar     J.Ramgarh       Dausa    Mean
 Water quality
                     (209)       (59)           (61)            (162)            (48)        (53)

 Good                 11.0       22.0           37.7             7.4             54.2       24.5     35.5

                                                  38
 Marginally saline           10.5          13.6      13.1           5.5        0.0            5.7       5.4

 Saline                      0.5              5.1     3.3           1.9        0.0            0.0       1.6

 Saline sodic                42.6          17.0       8.2           27.2       4.2            22.6     12.8

 E1 RSC water                17.2          16.9      16.4           22.2       29.1           7.6      22.6

 E2 RSC water                18.2          25.4      21.3           35.8       12.5           39.6     22.0

Source : Vyas et al. (1993)          ** Number of samples tested.

Table 2.18 : Classification of soils of different Tehsils of Jaipur Districts based on pH
                and EC
Characteristics Kotputali           Virat Nagar      Bassi            Chaksu           Jamva         Dausa
                                                                                      Ramgarh
 pH < 8.5             88.7             27.1          76.3             67.2             89.6           81.3
    > 8.5             11.3             72.9          23.7             32.8             10.4           18.7
 EC < 4.0             94.3             97.1          84.8             75.4             97.9           85.4
    > 4.0              5.7              2.9          15.3             24.6              2.1           14.6
                     Sambhar           Dudu         Amber             Phagi          Sanganer        Jaipur

 pH < 8.5             53.3             64.0          79.7             35.1             90.6          3.9
    > 8.5             46.7             36.0          20.3             64.9             8.4           36.1
 EC < 4.0             83.4             68.4          98.6             38.6             92.4          96.4
    > 4.0             16.6             32.6          1.4              61.4             7.5           4.6
(Vyas et al, 1993)




                                                        39
Bikaner district :
         Survey of underground waters of non-command area of Nokha, Kolayat,
Loonkaransar and Bikaner tehsils of Bikaner District revealed that water table of
tubewells varied from 36 to 208 m. EC and pH of tubewell waters varied from 0.8 to
10.3 dSm-1 and 7.1 to 9.0, respectively. The RSC were < 2.5, 2.5 to 5.0 and >5.0 mel-1 in
81.3, 16.3 and 2.4 percent of water samples , respectively. On an average 32.6, 16.3,
17.4, 12.8, 4.1, 9.3, 4.1 and 3.4 per cent samples were categorized as good, marginally
saline, high-SAR saline, high-SAR non-saline, saline, marginally alkali, alkali and highly
alkali, respectively. About 11.1, 42.9, 29.7 and 16.3 percent of the samples had salinity
<1.0, 1-2, 2-4 and >4.0 dSm-1, respectively (Lal et al.1998). The waters are mostly Na-
Mg-Ca type with dominance of chloride followed by carbonates + bicarbonates (Table
2.19 & 2.20). Water quality map of Bikaner is depicted in Fig.5




                                           40
        Analysis of surface soil samples collected from the fields irrigated with
corresponding water revealed that EC2 of all the soil samples is < 1 dSm-1 and soil is
alkaline in nature. Correlation studies revealed that EC of soil is positively and
significantly correlated with ECiw (r=0.411**) and potential salinity of irrigation water
(r=0.465**). Correlation between SARiw and SAR of soil was found positive (r=0.206)
but non-significant. It might be due to the fact that most of the wells are operating
since 1992 and onwards only.

 Table 2.19: Range of chemical characteristics of tube well/ well waters in Bikaner
               District

                                                 Tehsils of Bikaner
 Chemical                                                                             Bikaner District
 Characteristics                 Nokha      Kolayat         Loonkaransar   Bikaner      as a whole

 pH                              7.1-8.8     7.5-8.8            7.6-8.7    8.0-9.9        7.1-9.0

                 -1
 EC (dSm )                       1.0-6.1    0.8-10.3            2.3-7.9    0.8-7.7       0.8-10.3

          -2          -1   -1
 CO3 + HCO3 (mel )              2.5-12.5     2.5-8.4            3.0-5.8    1.6-7.8       1.6-12.5

     -1          -1
 Cl (mel )                      2.0-55.8    1.6-101.0         18.6-55.2    3.7-44.2      1.6-101.0

          -2
 SO4 ( ” )                        0-7.0     0.1-10.8                  --   Nil-31.9      Nil-31.9

      ++
 Ca            (”)              0.4-14.7     0.5-7.5            1.4-8.6    0.3-3.8       0.3-14.7

          ++
 Mg ( ” )                       0.9-12.8    0.9-18.9            2.9-7.2    0.4-11.8      0.4-18.9

      +
 Na            (”)              7.6-37.6    6.6-78.2          21.5-84.0    5.6-65.5      5.6-84.0

  +
 K             (”)              0.03-1.03    0.1-0.6            0.1-0.4    0.1-0.2       0.03-0.6

 RSC ( ” )                       Nil-8.1     Nil-5.8            Nil-4.2    Nil-4.8        Nil-8.1

 SAR                            3.3-22.4    4.7-30.8          12.9-27.4    5.3-41.8      3.3-41.8

 Adj. SAR                       8.4-43.9    7.9-58.2          25.8-68.8    9.3-73.2      7.9-73.2




                                                       41
 SSP                    28.0-91.3         47.9-90.2           78.6-88.9          60.1-95.1          28.0-95.1




Table 2.20 : Percentage distribution of water samples in different ranges of EC and RSC


                                                       EC (dSm-1)
 RSC
 (mel-1)
                   <1               1-2                2-3                3–4                >4         Total


 1                 2                 3                  4                  5                  6            7


 Nokha Tehsil


     < 2.5         --               48.4               17.7               11.3               6.5         83.9


 2.5 – 5.0         --               9.7                1.6                 --                 --         11.3


 5.0 – 7.5         --                --                1.6                 --                 --          1.6


     > 7.5         --               1.6                 --                1.6                 --          3.2


 Kolayat Tehsil


     < 2.5        3.0               27.3               12.1               12.1               21.2        75.7


 2.5 – 5.0        3.0               18.2                --                 --                 --         21.2




                                                  42
5.0 – 7.5          3.0       --          --     --     --     3.0


1                     2      3           4      5      6      7


Loonkaransar Tehsil


    < 2.5             --     --         33.3   46.7   20.0   100.0


Bikaner Tehsil


    < 2.5         24.2      19.4        11.3   3.2    19.4   77.5


2.5 – 5.0          1.6      16.1        1.6     --    3.2    22.5


Bikaner District as whole


    < 2.5          9.3      29.6        15.7   11.6   15.1   81.3


2.5 – 5.0          1.2      12.7        1.2     --    1.2    16.3


5.0 – 7.5          0.6       --         0.6     --     --     1.2


    > 7.5             --    0.6          --    0.6     --     1.2


                   11.1     42.9        17.5   12.2   16.3   100.0




                                   43
Churu Distrist:
         Verma et al. (2003) reported that in Churu district EC of water samples ranged
between 0.4 to19.7 dSm-1 (Table 2.21) About 32 per cent water samples have EC <2.0
dSm-1 while EC of 36 per cent samples fell between 2.0-4.0 dSm-1. Based upon EC it can
be stated that Sri Dungargarh tehsil is underlain with relatively better quality waters
followed by Sujangarh, whereas , water of North- Eastern tehsils viz. Churu, Taranagar,
Rajgarh and Sardarshahar are of marginal quality. pH of water samples ranged between
7.2 to 9.3. pH of more than 57 per cent water samples ranged between 8.1 to 8.5 while
only 3.0 per cent samples have pH less than 7.5. Tehsils of Northern part of district Viz;
Sardarshahar ,Taranagar and Rajgarh have waters of high pH (>8.5), as compared with
others . RSC of water varied between nil to 13.1 mel-1 . About 75 per cent water
samples recorded RSC <2.5 mel-1 whereas, about 9 and 16 per cent water samples had
RSC between 2.5 to 5.0 and >5.0 mel-1, respectively. Tube wells are relatively shallow
(<50 m) in Eastern part of district i.e. Taranagar, Rajgarh and Chruru tehsils, whereas,
tubewells are deeper in Sri Dungargarh , Sardarshahar and Sujangarh. Aquifer depth
from tube wells draw water varied from 7 to175 m.Mg/ Ca ratio >3.0 was in ground
waters of north-eastern tehsils of Churu district Viz. Sardarshahar , Churu ,Taranagar
and Rajgarh tehsils , while, it was between 1.0-2.0 in more than 75 per cent samples of
Sri Dungargarh and Ratangarh tehsils .The quality of under ground waters of Churu,
Taranagar, Rajgarh and Sardar Shahar tehsils of Churu district is poor. On an average
26.6 per cent samples fell under the category good, whereas, 15.3, 4.9, 28.7, 4.3 and
20.0 per cent samples were under marginally saline, saline, high SAR saline, marginally
alkali and high alkali, respectively (Table 2.22). Water quality map of Churu is depicted
in Fig.6




                                           44
45
Table 2.21: Range of chemical characteristics of tube wells / open wells
          water of Churu district

 Chemical            Sri     Sardar        Sujan       Ratan      Churu      Taranagar   Rajgarh     Churu
                 Dungar Garh Shahar        garh        garh                                          district
                    (87)*
 Characteristics
                             (93)          (101)       (67)       (61)       (23)        (124)


 pH                7.8-9.2     8.0-9.1     7.8-8.7     7.6-8.7    7.3-8.4    8.1-9.2     7.9-9.3     7.3-9.3

         -1
 EC (dS m )        0.4-4.1     0.6-8.6     0.8-11.6    1.1-4.8    2.1-1.4    1.9-19.7    1.7-18.2    0.4-19.7

              -1
 RSC (me l )       Nil-7.8     Nil-11.4    Nil-4.3     Nil-10.0   Nil-13.1   Nil-9.3     Nil-12.8    Nil-13.1


 SAR               1.0-17.7    2.2-31.4    1.7-21.7    3.4-1.5    6.9-7.7    6.2-33.5    8.4-27.9    2.2-33.5


 Adj . SAR         2.2-49.6    4.2-74.0    3.8-62.9    7.5-3.3    18.9-77.3 16.0-80.4    19.2-14.6   2.2-14.6


 SSP               23.0-87.5   43.7-95.1   31.6-84.8   49.0-91.7 16.0-90.9 46.6-93.2     46.4-1.0    16.0-3.2


 Mg/Ca             0.5-3.3     1.0-7.5     0.6-4.6     0.4-3.3    1.1-6.2    1.1-6.6     1.0-11.0    0.4-11.0


Water table (m)    35-152      40-87       20-175      38-133     23-50      7-37        10-61       7-175


 Soil


 pH                8.2-9.1     8.6-10.2    7.7-9.3     8.5-9.9    8.2-9.8    7.9-8.5     7.8-10.4    7.7-10.4

         -1
 EC (dSm )         0.1-0.6     0.1-0.8     0.1-1.9     0.2-1.2    0.3-2.3    0.7-1.9     0.4-2.3     0.1-2.3


 SAR               0.3-2.9     0.7-4.3     0.5-20.0    1.4-2.1    1.6-9.2    3.0-26.0    2.4-19.6    0.3-26.0

Source : Verma et al. (2003)        *Figure in Parenthesis indicate number of sample tested




                                                       46
Table 2.22: Percent distribution of water samples under different
          categories of water quality in Churu district.

Water quality       Sri     Sardar   Sujan   RatanG   Churu   Taranagar Rajgarh   Churu
                    Dunga   Shahar   garh    arh                                  district
                    garh

Good                72.4    11.8     49.5    32.9     --      --         1.6      26.6

Marginally saline   11.5    5.4      31.7    26.9     6.6     --         12.9     15.3

Saline              1.1     3.2      6.9     1.5      9.8     4.4        6.5      4.9

High SAR Saline     6.9     33.3     9.7     3.0      62.3    73.9       45.2     28.7

Marginally Alkali   3.4     7.5      2.0     11.9     --      --         3.2      4.3

Alkali              --      1.1      --      --       --      --         --       0.2

High Alkali         4.6     37.6     --      23.8     21.3    21.7       30.6     20.0

Nagaur district:
        Survey and characterization of underground waters of five tehsils (Nagaur, Jayal,
Ladnu , Kheenwsar and Merta ) of Nagaur district revealed that EC and pH of water
samples ranged between 0.61 to 11.9 dSm-1 and 7.0 to 9.3,respectively (Table 2.23). RSC
of water varied between nil to 14.1 mel-1. As regards salinity 2.3, 16.0, 41.3 and 40.2
percent water samples showed EC < 1.0, 1.0 - 2.0, 2.0 - 4.0 and > 4.0 dSm-1, respectively
in Nagaur tehsil. In Jayal tehsil 59.2 per cent water samples showed EC > 4.0 dSm-1. In
Jayal, Ladnu, Kheenwsar and Merta tehsils about 59.2, 33.9, 22.9 and 32.6 percent
water samples showed EC > 4.0 dSm-1, respectively (Table 2.29).On an average 10.6,
11.8, 4.7, 36.5, 3.5 and 32.9 percent water samples were under good, marginally saline,
saline, high SAR saline, marginally alkali and high alkali categories, respectively in
Nagaur tehsil, whereas in Jayal tehsil, about 10.2,15.3, 8.4, 47.3, 8.4 and10.2 percent
water samples were under good, marginally saline, saline, high SAR saline, marginally
alkali and high alkali categories, respectively. In Ladnu tehsil on an average 18.6, 40.7,
1.7, 33.9 and 5.1 per cent water samples were under good, marginally saline, saline,
high SAR saline and high alkali categories, respectively, whereas in Kheenwsar tehsil
28.3, 45.8 and 25.7 percent samples were under good , marginally saline and high SAR
                                             47
saline, respectively. In Merta tehsil about 34.1, 26.1 13.0, 26.1 and 0.7 per cent water
samples fell under good, marginally saline, saline, high SAR saline and marginally alkali
categories, respectively(Table 2.24). About 35.5 ,18.6 and 6.8 percent water samples
had RSC > 2.5 mel-1 in Nagaur, Jayal and Ladnu tehsils, respectively whereas kheenwsar
and Merta tehsils are free from RSC problem. Fluoride and Nitrate contents in under
ground irrigation waters of these tehsils ranged between nil to 16.5 and 0.2 to 148.4
mgl-1, respectively. The waters were Na:Mg:Ca type dominated with chloride anion.
Range of chemical characteristics of soil under tube well / open well irrigation water in
different tehsils of Nagaur district are presented in table 2.25.

Table2.23: Range of chemical characteristics of tube wells / open wells water of
             Nagaur district

 Chemical          Nagaur       Jayal            Ladnu        Kheenwasar   Merta            Range
 Characteristics   85*          59               59           70           138              411
 pH                7.8-9.2      7.9-9.1 (8.36)   7.0-8.6      7.2-8.7      7.31-9.3         7.0-9.3 (8.06)
                   (8.18)                        (7.68)       (8.08)       (8.00)

 EC                0.9-9.5      0.7-1.9          1.2-7.6      0.61-6.2(0   0.77-7.54        0.61-11.9
     -1
 (dSm )            ( 3.70)      (4.92)           (3.49)       (2.74)       (2.90)           (3.41)
 RSC               Nil - 14.1   Nil - 9.6        Nil-10.8     Nil-2.1      Nil-3.3          Nil-14.1
     -1
 (mel )
 SAR               2.6 - 34.7   2.2 - 48.6       3.5-48..2    2.1-25.5     1.3-28.7         1.3-48.6
 Adj . SAR         4.6 - 72.5   4.0 - 102.1      9.8-90.0     4.0-53.9     3.0-67.2         3.0-102.1
 SSP               36.3 -94.0   32.6 - 95.0      36.1-94.9    38.9-88.6    21.4-91.3        21.4-95.0
 Mg/Ca             0.6 - 4.9    0.7-4.5 (2.73)   0.6-         0.7- 4.0     1.0-8.6 (3.00)   0.6-8.6
                   (2.07)                        5.7(2.85)    (1.78)                        (2.54)
 Nitrate           0.3-19.3     1.2 - 56.0       0.4-66.8     2.0-62.0     0.2-148.4        0.2-148.4
      -1
 (mg l )
 Fluoride          Nil - 11.8   Nil - 12.0       0.5 - 16.5   0.7 -4.0     0.1-9.1          Nil-16.5
      -1
 (mg l )
 Water table       32.7-134.0   30.0 - 100.0     40.0-133.3   53.3-153.3   16.3-150.0       30.0-153.3
 (m)
Source : Verma et al. (2005) *Number of sample tested Figure in Parenthesis are the average value

Table 2.24:          Distribution (percent) of water samples in different ranges of
                     EC and RSC in Nagaur district


                                                      48
                                         -1
                                   EC (dSm )
          -1
RSC (mel )
                    <1     1-2    2-3          3-4    >4     Total

Nagaur Tehsil

<2.5                2.3    8.0    3.4          13.8   36.8   64.3

2.5-5.0              -     3.4    2.3          2.3     -      8.0

5.0-7.5              -     4.6    8.1          3.4    2.3    18.4

> 7.5                -      -     3.4          4.6    1.1     9.1

Jayal Tehsil

<2.5                3.4    6.8    13.6         6.8    50.8   81.4

2.5-5.0              -     3.4    3.4           -     8.4    15.2

5.0-7.5              -      -      -           1.7     -      1.7

> 7.5                -      -     1.7           -      -      1.7

Ladnu Tehsil

<2.5                 -     20.3   35.6         8.5    28.8   93.2

2.5-5.0              -      -      -            -     1.7     1.7

5.0-7.5              -      -      -           1.7    1.7     3.4

> 7.5                -      -      -            -     1.7     1.7

Kheenwasar Tehsil

<2.5                17.1   12.9   32.9         14.2   22.9   100.0

Merta tehsil

<2.5                2.9    31.9   16.7         15.2   32.6   99.3

2.5-5.0              -      -      -           0.7     -      0.7




                                  49
 Table 2.25: Percent distribution of water samples under different categories of water
                  quality in Nagaur district.

 Water                quality                                              Tehsils
 categories                        Nagaur                  Jayal            Ladnu      Kheenwasar        Merta


 Good                                   10.6               10.2              18.6          28.5             34.1
 Marginally saline                      11.8               15.3              40.7          45.8             26.1
 Saline                                 4.7                 8.4               1.7            -              13.0
 High SAR Saline                        36.5               47.3              33.9          25.7             26.1
 Marginally Alkali                      3.5                 8.4                 -            -              0.7
 Alkali                                  -                   -                  -            -               -
 High Alkali                            32.9               10.2               5.1            -               -



 Table 2.26: Range of chemical characteristics of soil under tube well / open well
               irrigation water in different tehsils of Nagaur district

                                                                          Tehsil
 Chemical
                            Nagaur             Jayal                    Ladnu         Kheenwasar    Merta
 Characteristics
                            78*                46                       43            53            138
 pH                         7.8-10.0           8.4-10.0                 8.5-9.7       7.3-9.6       7.2 -10.4
                            (8.91)             (9.07)**                 (9.02)        (8.79)        (8.81)
           -1
 EC (dSm )                  0.2 - 3.1          0.18-4.68 (1.05)         0.16-1.37     0.18 - 4.26   0.19-3.36
                            (0.87)                                      (0.44)                      (0.66)
 Ca (mel )
                -1
                            0.4 - 7.8          0.3 - 9.0                0.4 -1.3      0.3 -10.1     0.3 - 7.6
               -1
 Mg (mel )                  0.3 - 6.8          0.5 - 8.8                0.4 -1.4      0.3 -11.6     0.4 - 11.0
           -1
 Na (mel )                  1.0 – 29.0         1.1 - 21.8               0.8 -12.2     0.7 -17.0     1.1 - 28.9
          -1
 K (mel )                   0.1 - 0.5          0.04 - 0.99              0.04 - 0.38   0.02 - 0.28   0.03 -1.0
     --      - -1
 CO3 +HCO3 (mel )           0.9 - 8.3          0.6 - 3.6                0.9 - 2.2     0.6 - 2.5     0.6 - 7.9
   -    -1
 Cl (mel )                  0.7 – 29.7         0.9 - 44.0               0.7 -10.8     0.8 - 26.0    0.6 - 30.4
     --    -1
 SO 4 (mel )                0.2 - 3.4          0.2 - 8.7                0.19 - 3.35   0.13 - 4.28   0.15 - 3.71
 SAR                        1.2- 28.8          1.6 - 19.8               1.0 - 13.5    0.8 - 10.5    0.7 - 18.4
* Number of samples tested **Figures in parenthesis are the average values


Salinity levels:

                                                                   50
         It has been reported that in areas in the north-eastern and southern parts of
Rajasthan (Jaipur, Kota and Udhaipur where rainfall > 500mm), the ground waters have
residual alkalinity in significant amounts. Ground waters of Nagaur, Sikar and
Jhunjhunnu districts also have high residual alkalinity. Salinity of ground waters in
shallow aquifers of eastern Rajasthan is generally <2 dSm-1. Ground water salinity
increases towards north and north-east Rajasthan. Over 4 dSm-1 of ground water salinity
is found in major parts of eastern Rajasthan, namely Bharatpur, Tonk, Sawai Madhopur
and Ajmer districts . Phreatic ground water with EC more than 8 dSm -1 was analysed in
major portions of Barmer and Jaisalmer districts except western, central and south
central parts where ground water is fresh and potable; western half of Bikaner district
and major parts of Ganganagar district except along Gaggar flood plains.In south-
eastern, northern and north- eastern parts of Churu district salinity is above 8 dSm-1.
Saline ground water with EC>8 dSm-1 is common in Nagaur district,central parts of
Bharatpur district and in very small pockets in the vicinity of Sambhar lake in Jaipur and
Ajmer districts. Salinity levels in shallow ground water varies widely from good to as
much as 47 dSm-1. In respect of western districts the upper limit of salinity in ground
water ranges upto 47 dSm-1 , whereas, in the eastern districts it is upto 13 dSm-1 . In a
localized area around Sitapur and Todara in Sawai Madhopur district salinity is around
21 dSm-1. Brine deposits with salinity (TDS >240000 ppm) in saltlake depression area
around Pachpadra (Barmer district), Phalodi (Jodhpur district), Sambhar lake ( Jaipur
district) , Didwana ( Nagaur district) and in depression areas of Bharatpur district is
unique. In deeper aquifers the upper limit of salinity reaches as high as 58 dSm -1 in
Barmer district, 23 dSm-1 in Bharatpur district and 47 dSm-1 in Pali district.

Fluoride:
         Fluoride occurs in ground waters in all the districts of Rajasthan, irrespective of
salinity . Somani et al. (1972) reported that well water from Nagaur and Jaipur district
contained 4.5 and 28.1 mgl-1 fluorine with a mean value of 5.5 mgl-1. Further, in Udaipur
district Somani (1974) found a mean value of 4.8 mgl-1 with a range of 0.18 to 21.6 mgl-1
fluorine. Positive correlation was found between fluorine with depth of water table and
sodium content of water (Somani, 1974; Singh and Sisinwar ,1975). Sinsinwar et.
al.(1981) reported that fluoride content in well waters of Srigagangar district ranged

                                               51
from 0.10 to 28.2 mgl-1. Gupta (1986) observed 40 per cent water samples in Pali and
Jalore districts containing fluoride concentration above the permissible limit of 2.0 mel-1.
Singh and Anand (1991) reported that ground water of Jhunjhunu district is suitable for
drinking purpose but at some locations fluoride content exceeds 30 mgl-1. Ozha and
Sharma (1993) while making investigation of 1870 water samples from Nagaur, Barmer
and Jalore districts of western Rajasthan found that more than 50 per cent water
samples had fluoride concentration > 1.5 mgl-1 and the problem was more acute in
Nagaur district.They noted 34 mgl-1 fluoride in these waters . The problem of high
fluoride was equally serious in southern -eastern part of state as Gupta et al. (1983)
noted 10 to 20 per cent water samples in Banswara, Bundi, Rajsamand and Udaipur
and more than 25 per cent samples of ground waters of Ajmer, Bhilwara, Dungarpur and
Kota districts had > 1.5 mgl-1 fluoride. The situation found to be most grim in Bhilwara
and Ajmer districts where 47.6 and 63 per cent water samples, respectively showed
this condition. Highest 16.2 mgl-1fluoride was noted in Ajmer by them in their study.
Baran, Chittorgarh and Jhalawar districts presented better picture with respect to
fluoride where more than 90 per cent water samples were found to be in safe limit. In
arid and semi arid regions of Rajasthan the percentage of waters having fluoride higher
than 10.0 mg L-1, is very small(< 5) and the highest concentration is 30 mg l-1 except
Nagaur district, where it occurs up to 90.0 mg L-1 ( Anonymous, 2000 ;Table
2.27).Bagoria (2002) reported that fluoride content of Nagaur tehsils ranged between
0.10 to 11.0 mg L-1 and about 20 percent water samples were found to have fluoride
content within permissible limit as per W.H.O.




                                               52
Table 2.27: Percentage wise distribution of fluoride (mgl-1 ) in    ground waters of
              Rajasthan.

                                                                    -1
 District                       No. of                  Fluoride (mgl )
                               Samples
                                             <5        5-10         >10      Max

 Barmer                          537        73.1       9.1          2.8      19.6

 Bikaner                         144        91.9       7.6          1.4      12.0

 Churu                           316        92.1       6.6          1.3      30.0

 Jaisalmer                       268        97.4       2.6           -       5.0

 Jalore                          165        92.3       9.1          0.6      14.2

 Jodhpur                         704        89.9       9.1          1.0      22.0

 Nagaur                          1080       83.9       11.4         4.7      90.0

 Pali                            236        89.4       8.5          2.1      18.3

 Ganganagarh &Hanumangarh         84        97.6       1.2          1.2      26.0

 Sikar                           314        95.6       4.4           -       15.0

 Sirohi                          597        98.5       1.5           -       11.0

 Jhunjhunu                       295        95.0       5.0           -       12.0

 Jaipure                         120            -       -            -       28.1

 Bhilwara                         -             -       -            -       24.0

 Udaipur                         166            -       -            -       21.5

 Bharatpur                       100            -       -            -       21.5

 Tonk                             -             -       -            -       18.4

 Alwar                            -             -       -            -       7.6
Source: Anonymous,2000




                                           53
Nitrate:
       In Barmer, Jaisalmer and Bikaner districts about 45, 18 and 25 percent water
samples were in the range of < 20, 20-50 and 50-100 mgl-1 nitrate, respectively (Gopal
et. al. 1983; Table 2.28). Singh and Anand (1991) reported that ground water of
Jhunjhunu district is suitable for drinking purpose but at some location nitrate content
exceeds 100mgl-1.Ozha and Jain (1992) noted greatest frequency of water having nitrate
above 100 mgl-1in Churu district (76.0%) followed by Nagaur (53.7%),Barmer (53.7%)
and Jalore (41.0% ) district. Lower frequency (3.04%) of such water was recorded in
Bikaner district. In an another study of Ozha and Sharma (1993) in Churu district
maximum nitrate level was recorded as 2400 mgl-1and only 14.2 per cent of water
samples contained nitrate up to 50 mgl-1. In Barmer district the maximum recorded
Nitrate value was 1900 mgl-1 and 32 per cent samples contained nitrate up to 50 mgl-1.
Rai and Gulati (1997) reported a range of 15 to 590 mgl- 1 nitrate in 60 well water
samples of Jodhpur. They recorded the nitrate levels in 55 out of 60 wells beyond
maximum permissible limit.About 75% water samples having nitrate >100 mgl-1 was
reported in Churu district (Anonymous,2000 ; Table 2.29)

Table 2.28: Distribution percent of nitrate in ground water of some         districts of
                western Rajasthan

          -1
 NO3 (mgl )               Barmer       Jaisalmer         Bikaner           Average


 <20                          18          50               66                45


 20-50                        8           19               27                18


 50-100                       63          22                2                25

Source: Gopal et al. (1983)




                                               54
Table 2.29: Percentage wise distribution of nitrates (mgl-1 ) in waters of Rajasthan.

                                                                              -1
                                                                Nitrate (mgl )
 Climatic zone             District
                                                   Max.    <50        50-100       >100

 1                         2                        3       4            5          6

 Arid *                    Barmer                  1600    32.0         13.2       54.8

                           Bikaner                 2100    47.0         16.7       36.2

                           Sriganganagar           533     72.0         13.9       13.9

                           Hanumangarh             780     56.0         20.0       24.0

                           Jaisalmer               1400    62.7         10.4       26.8

                           Jodhpur                 2800    41.0         21.0       37.9

 Arid-cum semi-arid *      Churu                   2350    16.2         8.2        75.7

                           Jalore                  600     56.4         10.9       32.7

                           Jhunjhunu               544     51.8         23.4       24.6

                           Nagaur                  4750    31.0         16.8       52.1

                           Pali                    1400    71.6         16.1       12.2

                           Sikar                   748     47.4         24.0       28.6




 1                         2                        3       4            5          6



                                              55
Semi-arid**                 Ajmer                   730    57.4          20.9             22.1

                            Alwar                   1350    30            30               40

                            Bharatpur               825     70             ----------30----------

                            Bhilwara                1010    65            16               19

                            Dausa                   780      -             -                -

                            Dhaulpur                300      2             -                -

                            Jaipure                 2640    37            42               21

                            Karauli                 460      -             -                -

                            Sawaimadhopur           1100     -             -                -

                            Tonk                    1050    72           12.3             15.8

Sub-humid **                Bundi                   395    92.2            -               7.8

                            Chittaurgarh            270      -             -                -

                            Rajsamand               370    ---- -89 ------------           11

                            Sirohi                  395      8            9.3             10.7

                            Udaipur                 472    68.7          21.3             10.0

Humid**                     Banswara                206     83            7.4               3

                            Baran                   370    89.3           6.1              4.6

                            Dungarpur               408    87.2           4.3              8.5

                            Jhalawar                397     83            10               7.0

                            Kota                    650    83.4          11.0              5.7
Source: Gupta (2000)*; SRSAC &7 GWD (1999)**



Boron:

                                               56
        In Rajasthan Boron in irrigation waters is quite high and ranges from traces to as
high as 5 mgl-1 in some well waters of Nagaur, Jaipur, Sirohi, Jodhpur, Bhilwara and Pali
districts. Mandal (1967) reported that boron content of different kinds of underground
water used for irrigation in Rajasthan varied from 0.28 to 7.66 mg l-1 Examination of
boron content of 452 ground water samples from several districts of Rajasthan reveal
the content lesser than 3 mgl-1 (Paliwal, 1972). However, 10.7 mgl-1 boron has been
reported in ground water of Bikaner district having EC 15.0 dSm-1 (Gajbhiye et al. 1973).
Boron content of well waters of Rajasthan as reported by different workers is given in
table 2.30.

Table 2.30 : Boron content of well waters of Rajasthan

                                             -1               -1
District       No. of samples    Range (mgl )          Av. (mgl )   Authors

Nagaur         74                0.05-3.1              1.28         Paliwal & Gandhi,1969

Bhilwara       59                0.13-1.62             0.75         Paliwal & Maliwal,1966

Pali           19                0.62-3.1              1.28         Paliwal & Maliwal,1966

Jodhpur        11                0.62-2.18             1.32         Paliwal & Maliwal,1966

Jalour         110               0.50-5.0              1.33         Anonymous,1964

Kota           65                0.10-3.0              0.95         Mathur et al. 1969

Jaipur         85                Tr.-6.0               1.80         Paliwal & Maliwal,1966

Bikaner        137               0.22-10.7             -            Gajbhiye et al . 1973

Bharatpur      100               Tr.- 4.4              -            Gupta. 1979

Udaipur        166               0.05-4.1              0.4          Gupta. 1979



Lithium :
         Gupta and Sanganeria (1979) analysed 126 ground water samples from Udaipur
district in Rajasthan. Lithium content varied from 0-0.39 mgl-1 with an average value of
0.05 mgl-1 in waters having EC 0.34 to 9.2 dSm-1. Lithium content increased with


                                                  57
increase in salinity.The percentage of water samples having lithium <0.05 and 0.05 to
0.5 mgl-1 was 34 and 46, respectively

Other trace elements:
      Gupta and Sanganeria (1979) determined the trace elements in ground water of
Udaipur district having EC 0.34 to 9.2 dSm-1 which are presented in Table 2.31

Table 2.31: Trace elements in ground water of Udaipur district (mgl-1 )


       Elements                   Min.               Max.                  Average


          Cu                           0             0.19                   0.019


           Fe                          0             3.00                   0.41


          Mn                           0             2.05                   0.074


           Zn                      0.06              1.25                   0.147

Source : Gupta and Sanganeria (1979)


Ground water quality in IGNP:
        The chemical quality of ground water is largely saline except along Ghaggar
plains. The EC of ground water ranges between 0.48 to 39.6 dSm -1. Chemical quality
along Ghaggar plains in upper horizon ( up to a depth of 25 to 30m) was observed to be
fresh. It is evident from the data (Table 2.32) that a fresh cushion is developed over the
saline native ground water mainly due to continuous recharge from different sources.
The exploitable fresh ground water zones are mainly restricted in Ghaggar bed in the
proximity of main canal and distributory systems.

Table 2.32: Changes in chemical quality in IGNP Phase I:

                                              58
 Site               1993-94       1994-95      95-     96-       98-       1999-2k     2k-01   01-    02-
                                               96      97        99                            02     03

                   EC *   pH     EC     pH     EC      EC         EC      EC     pH     EC      EC    EC

 Anupgarh          0.86   7.5    0.79   9.9    0.68    0.78      0.85     0.65   8.1   0.61    0.70   0.80

 Ramsingh pur      1.45   9.8    1.70   8.8    1.58    1.05      1.20     1.20   8.1   1.14    1.23   1.10

 Sangeeta          1.30   8.5    1.38   8.6    1.40    1.44      1.60     1.68   8.1   1.36    1.47   1.71

 Manaksar          0.56   9.0    0.64   8.4    0.70    0.48      0.60     0.61   8.1   0.61    0.63   0.64

 Rangmahal         9.65   8.4    12.2   8.8    8.20    8.50      12.35    11.8   7.9    10.6   10.0   8.80

 Badopal           0.74   7.8    0.63   8.7    0.99    1.00      2.00     0.87   8.0   1.14    1.01   1.15

 Bherusari         1.60   8.5    1.40   8.8    1.23    0.80      2.55     0.72   8.0   0.82    1.30   1.23

 Khetawali         1.87   9.0    2.04   8.1    2.08    1.95      0.80     2.10   8.0   1.91    1.65   1.81

 Dubali Khurd      0.98   8.3    1.40   8.5    0.99    0.85      38.0     1.15   7.9   0.73    1.46   0.89

 29DWD              -      -     33.6   7.1     -      14.0      9.80     39.5   9.8    41.8   41.3   30.6

 Basir             7.00   8.7    8.36   8.6    8.00    7.8       6.20     6.93   8.1    9.6    8.87   7.39

 Lakhuwali         7.60   9.3    6.20   8.6    6.00    6.10           -   6.00   7.8   6.07    6.13   6.13

 Manaktheri        0.96   9.0    0.84   9.0     -      0.70           -    -      -    1.61    1.58   1.55

                                                                 -1
Source : Annual Report, CAD (2003-04) * EC is expressed in dSm

        Data on changes in chemical quality of ground water in IGNP Phase II (Table
2.33) indicated that in general native ground water is saline having EC about 10.0 dSm -1.
However chemical quality in the vicinity of canals is better with EC values of 3.0 dSm -1,
which shows that fresh water horizon , is developing gradually. This fresh water cushion
has a significant thickness at places , which can be attributed to the percolation ,
seepage of water from irrigation network developed in the area.

Table 2.33: Changes in chemical quality in IGNP Phase II

                                                      59
 Site                  1993-94       1995-96        96-        97-    98-99         99-    2k-    01-    02-
                                                    97         98                   2k     01     02     03

                       EC      pH    EC       pH    EC         EC     EC      pH    EC     EC     EC     EC

 ManaksarDy.RD 100     0.9     7.7   1.05     8.5   0.73       0.55   0.60    7.9   0.99   1.41   1.35   1.39

 Chakosa               10.15   7.1   9.00     7.7   9.40       8.28   9.81    8.0   10.6   10.3   9.6    9.83

 Ramai                 10.57   7.5   10.50    8.0   9.80       9.00   8.90    8.1   10.0   10.3   10.1   10.3

 Adhuri head           0.74    8.2   0.92     8.9   0.70       0.84   0.80    8.2   4.48   4.36   4.41   4.79

 Adhuri village        6.70    8.0   3.30     8.5   3.00       2.95   3.60    8.0   4.48   4.36   4.41   4.48

 Makheri               12.90   7.9   14.40    7.8   14.7       11.0   13.90   7.9   13.0   14.0   13.8   13.7

 IGN 1381 RD           0.55    8.8   0.93     7.9   0.91       0.45   0.30    8.0   0.64   0.59   0.61   0.65

 Tanwarwala            15.00   7.8   15.30    8.1   15.6       12.1   15.90   8.1   16.3   16.5   16.4   16.5

 IGN 1458RD            0.52    8.9   0.70     8.5   0.94       0.68   0.51    8.2   0.56   0.80   0.82   0.71

 Deli Talai            2.53    8.5   1.68     8.6   2.88       1.75   1.95    8.0   1.71   1.76   1.87   1.91

 Jaggasar              1.56    8.2   0.94     8.6   1.35       1.51   0.90    7.9   0.74   0.83   0.83   0.85

 Cholewali Dy.R D10    2.61    7.6   3.70     9.2   0.54       0.51   0.58    8.0   0.56   0.61   0.63   0.68

 SBS 17 RD             -       -     -              7.60       7.25   6.70    8.0   8.80   8.50   8.70   8.78

 JJW 53 RD             -       -     -        -     7.80       1.31   3.00    8.2   5.90   6.35   6.55   9.01

 TuliDy.00RD8.         -             -        -     12.9       13.9   13.70   8.1   12.5   6.74   6.78   14.7

 Sadhan Dy. 165 RD             -     -        -     9.30       13.9   18.8    8.0   17.4   18.0   18.2   18.4

 SMG 90 RD             -       -     -        -     23.9       26.6   29.2    8.1   28.9   29.0   29.3   29.4

 Nedai                 -       -     -        -     13.2       34.1   22.9    8.1   23.4   23.9   24.6   24.7

 Arjana                -       -     -        -     8.70       8.80   9.0     8.2   8.2    7.74   7.50   7.45

Source : Annual Report, CAD (2003-04)     * EC is expressed in dSm-1

        Dogne (1995) studied soils of Kanwar Sen Lift Canal area of IGNP, and classified
into different categories, based on the USDA classification. Out of 50 chacks, 29 chacks
had sodic soils, 7 chacks saline sodic, 11 chacks saline soils and 3 chacks had both saline
and saline sodic soils. Prakash (2001) reported that the salt accumulations were found
more in sub surface soils as compared to surface soils. On the basis of salinity and
alkalinity indices, the surface and sub surface soils have moderate salinity and slightly

                                                          60
alkalinity problems in the soils of Kanwar Sen Lift Canal area of IGNP, Bikaner
(Rajasthan).

        For computation of ground water resources of Rajasthan ground water with
electrical conductivity over 8 dSm-1 in the districts of western Rajasthan (3, 42,226 km2
geographical area) and over 6 dSm-1 in the districts of eastern Rajasthan has been
taken by the state ground water department as unsuitable for any use and thus taken
as saline ground water areas. A total of 1, 06,018 km2 area (about 31% of Rajasthan)
comes under saline ground water in the state. Of this 88675 km2 area falls in western
districts viz. Ganganagar, Barmer, Bikaner, Churu and Jaisalmer. District-wise saline
areas are given in Table 2.34.

Table 2.34: Saline ground water areas in Rajasthan

 District             Geographical   Saline area EC    Percent of      Saline area   EC   Percent of
                                             -1   2                            -1  2
                      area           > 6dSm (km )      district area   > 4dSm (km )       district area
                          2
                      (km )
 Ajmer                8481            587              6.9          700                  8.2
 Alwar                8380            476              5.7          1200                 14.3
 Barmer               28367           14830            52.2         18750                66.0
 Bharatpur            5100            1380             27.1         3060                 60.0
 Bikaner              27244           15683            57.6         19750                72.4
 Churu                16830           10389            61.7         11780                69.9
 Dausa                 3472           101              2.9          370                  10.6
 Ganganagar           20634           18347            88.9         19000                92.2
 Jaipur               11066           566              5.1          900                  8.1
 Jaiselmer            38401           29426            76.6         31426                81.8
 Jalore               10640           2123             19.9         7020                 65.9
 Jhunjhanu             5923           119              2.0          400                  6.7
 Jodhpur              22850           5349             23.4         11000                43.1
 Nagaur               17718           2485             14.0         6500                 36.6
 Pali                 12307           3188             25.7         4550                 36.7
 Sawai Madhopur       10057           176              1.7          200                  1.9
 Sikar                7732            93               1.2          350                  4.5
 Tonk                 7194            695              8.7          750                  10.4
 Total geographical   342260          106018           31           141036               41
 area
                                                         -1                                  -1
Note: EC of ground water in western Rajasthan over 8 dSm and in eastern Rajasthan over 6 dSm
Source: Minhas and Samra(2003)



                                                      61
Hydro-geology:
        Hydro-geogical studies indicate that state has three types of Aquifers: (a)
Unconsoli -dated formations (alluvial and aeolian deposits) associated with residual hill
slopes, abandoned river courses, the piedmont plains, aeolian plains of Jalore, Barmer
and Jodhpur districts and catchments of river Katali in Jhunjhunu, Luni in Ajmer, Banes
and Khari rivers in Udaipur, Tonk and Bhilwara districts; (b) in districts of Jaisalmer and
Barmer, aquifers are in semi-consolidated sedimentary rock formations, Lathi stone
formations in about 10000 km2 (2.9%) area have proved to be promising aquifers and (c)
Aquifers in regions having consolidated rock formations have some water that can be
used for agriculture. District wise aquifers in potential zones and area (Sq.Km.) are
given in table 2.35.

Table 2.35 : District wise aquifers in potential zones and area (Sq.Km.)

 S.No. District                         Aquifers in potential zones and area (Sq.Km.)
     1           2                                             3
 1       Ajmer         Alluvium (332.5), Calc- schist ( 2002.6) , Granite-gneiss(5121.7)
 2       Alwar         Older Alluvium (5820.7), Quartzites (545.4), Slate (667.4)
 3       Banswara      Aasalt (1238.4), Lime stone (80.6), Quartzites( 78.4), Phyllite & Schist(1005.5),
                       Granite-gneiss ( 986.5)
 4       Baran          Sand stone (3830.6) ,Alluvium ( 274.7),Basalt (966.8)Shale (637.1) Lime stone
                       (1183.0)
 5       Barmer        Younger Alluvium ( 1540.0 ) , Older Alluvium (5614.5) Tertiary sand stone
                       (2084.2) Lathi sand stone (1497.8) , Rhyollite
                       ( 1306.4) Granite (303.3)
 6       Bharatpur     Older Alluvium(1544.5) Sand Stone (1487.5) , Quartzite ( 76.9)
 7       Bhilwara      Phyllite & Schist (4325.8), Granite-gneiss ( 4541.7) Sand stone (428.7) , Lime
                       stone (60.7)
 8       Bikaner       Older Alluvium(1544.5) Tertiary Sand Stone (6287.0) , Nagaur sand stone
                       (3248.4),Bilara sand stone ( 172.1)
 9       Bundi         Alluvium (1158.3) ,Phyllite (1667.5) , Sand stone (404.4) , Lime stone (247.8),
                       Shale (126.7), Lime stone with Shale (635.4)
 10      Chittorgarh   Basalt ( 1715.3), Granite-gneiss( 1787.5), Sand stone (697.2), Lime
                       Stone(467.1), Shale ( 1991.9), Phyllite & Schist (1551.0)
 11      Churu         Younger Alluvium (1920.2) , Older Alluvium (1361.2) Tertiary Alluvium (1049.8
                       , Nagaur lime stone (1267.3), Bilara lime stone (488.0), Jodhpur sand stone (


                                                     62
                   353.7)
 1            2                                            3
12   Dausa         Younger Alluvium (709.2) , Older Alluvium (1902.9) , Quartzite
                   ( 327.4), Phyllite (52.5), Granite-gneiss (73.7)
13   Dhaulpur       Schist Alluvium (1430.0) , Sand stone (801.4)
14   Dungarpur     Ultra base (81, Biotic Schist (282), Phyllite & Schist (1998.2), Granite-gneiss
                   (287.6)
15   Ganganagar    Alluvium (1925.4)
16   Hanumangarh   Alluvium (920.7)
17   Jaipur        Younger Alluvium (4383.5) , Other Alluvium (2829.0) Quartzite (540.7, Phyllite
                   & Schist(704.6), Granite-gneiss ( 1431.9)
18   Jaisalmer     Alluvium (2706.5), Tertiary sand stone (716.6),Parwar sand stone (784.1),
                   Bhadesar sand stone (462.0) , Jaisalmer sand stone ( 568.8), Lathi sand stone (
                   4502.2), Jodhpur sand stone (695.3), Granite (209.4), Rhyollite (336.3)
19   Jalore        Younger Alluvium (1378.4) , Older Alluvium (6099), Granite (582.4), Phyllite
                   (68.8)
20   Jhalawar      Basalt (4732.1), Sand stone (1374.1
21   Jhunjhunu     Younger Alluvium (299.2) , Older Alluvium (4220.4), Quartzite schist, Phyllite
                   Lime stone and Granite (754.1)
22   Jodhpur       Older Alluvium (826.8),Nagaur sand stone (790.4) Bilara Lime stone (2821.4),
                   Jodhpur sand stone (10106.8), Rhyllite (383.1),Granite (1596.7)
23   Karauli       Older Alluvium and Quaternary (2338.2), Sand stone (1454.9), Quartzite
                   (108.7)
24   Kota          Alluvium (1410.3), Lime stone (1180.5), Sand stone (235.9), Shale (151.5)
25   Nagaur        Other Alluvium (5682.0), Palana sand stone (1005.3), Nagaur sand stone
                   (2505.1) , Bilara lime stone (3363.6), Jodhpur sand stone (1341.3), Phyllite ,
                   Schist & Gneiss (2481.2)
26   Pali          Younger Alluvium (81.2) , Older Alluvium (236.1), Erinpura Granite (3140.6) ,
                   Slate , Phyllite & Schist (1623.4), Granite-gneiss (704.2)
27   Rajsamand     Mica Schist , Phyllite & Schist (251.2), ), Granite-gneiss (1735.9)
28   Swai          Alluvium (2256.3), Lime stone (583.9) , Shale (529.6), Quartzite (164.9) ,
     Madhopur      Phyllite & Schist (790.9),
29   Sikar         Younger Alluvium (165.2) , Older Alluvium (6010.9),Quartzite , Dolomite, Lime
                   stone, Schist, Phyllite & Gneiss (1087.3)
30   Sirohi        Alluvium (987.8), Calc. Schist & Gneiss (525.4), Phyllite & Schist (1543.4) ,
                   Granite (1550.5)
31   Tonk          Alluvium (1307.8), Phyllite & Schist (4203.8), Granite & Gneiss (1014.2)
32   Udaipur       Calc. Schist & Calc. Gneiss(825.8), Granite (253.1), Quartzite (151.7) Phyllite &
                   Schist (3729.1) ), Granite & Gneiss (3300.8)




                                                63
       Major parts of the saline areas are restricted in the Quarternary alluvial deposits
which comprises of silt, sandy clay, ‘kankar’ etc. of Eesozoic and tertiary age and form
saline aquifers in the Barmer, Bikaner, Jaisalmer, Churu, Jodhpur districts. In the
western districts the thickness of uncosolidated sediments is more than 300m. Semi
consolidated formations occur as discontinuous aquifers with limited thickness down
to100 m. The depth to water levels varies very widely in the western districts ranging
from about 10m in south western parts of Jalore district to as much as about 100 m in
parts of Jaisalmer and Bikaner districts. In 1999-2000, 68.9% of total irrigated area
5.61million ha. was served by ground water, 28.8% by canals and remaining 2.3% by
tank etc.

Ground water potential in Rajasthan:
        Due to scarcity of surface water , Rajasthan has to depend on ground water
resources to a great extent .Ground water potential area in the state is 215142 sq.
km.The fresh ground water resource has been made block wise in respect of Rajasthan
as per guide lines given by the Ground Water Esimation Committee. Saline ground water
areas with electical conductivity over 8 dSm-1 in western Rajasthan and over 6 dSm-1 in
eastern Rajasthan were excluded from the usable ground water areas. On adhoc basis a
very approximate estimation of dynamic recharge in the saline areas is of the order of
2790 MCM per annum (Table 2.36).




                                              64
Table 2.36: Saline ground water resources in Rajasthan

 District              Annual recharge (MCM/yr) (for saline   Annual recharge (MCM/yr) (for saline
                                                         -1                                      -1
                      areas where GW salinity EC > 8dSm in    areas where EC of GW is over 4dSm
                                                      -1
                        western Rajasthan and >6dSm in
                                eastern Rajasthan

 Ajmer                               20.05                                   23.83

 Alwar                               52.92                                   130.92

 Barmer                              423.28                                  537.34

 Bharatpur                           138.00                                  305.79

 Bikaner                             332.17                                  418.09

 Churu                               310.35                                  351.49

 Dausa                                9.10                                   32.97

 Ganganagar                          464.07                                  480.51

 Jaipur                              26.23                                   44.51

 Jaiselmer                           372.08                                  397.28

 Jalore                              80.00                                   264.47

 Jhunjhanu                            8.31                                   26.71

 Jodhpur                             170.60                                  349.66

 Nagaur                              85.53                                   222.33

 Pali                                213.23                                  306.77

 Sawai Madhopur                      16.11                                   18.15

 Sikar                               16.61                                   59.92

 Tonk                                50.36                                   53.93

 Total geographical                 2790.00                                 4024.67
 area
Source: Minhas and Samra(2003)




                                                  65
The ground water resources position as on 1.1.95         & 1.4.98     is given below (
            Annonymous, 2000)

                                            1. 1.95                    1.4.98

 The ground water resources               13157.2 MCM               12602.1 MCM

 Utilizable ground water for irrigation   11028.2 MCM               10604.4 MCM

 Utilized for irrigation                  6493.7 MCM                7724.5 MCM

 Ground water balance                     4534.5 MCM                2879.9 MCM

 Stage of ground water development          58.9 %                    72.8 %




       In 2001 ground water development was 104% with a net negative balance of –
476.0 MCM and 70% of the assessment blocks were in critical and over exploited
category of water table. In major parts of the western districts average depth is
between 40 to 70 m bgl. In the saline areas of eastern districts groundwater rests at
depth ranging from 10m to 40m below ground level.

Present use:
         About two third area of western Rajasthan and parts of eastern Rajasthan are
underlain with saline ground water and potable water sources are not available as such.
Ground water with EC 8 dSm-1is being used for irrigation , drinking and other domestic
uses. Such water have unpalatable taste and may cause adverse effect on health. Saline
water is also being used for livestock as they have higher tolerance to saline water. To
provide safe drinking water, the State Govt. has commissioned a total of 91 desalination
plants (50 R0 and 41 ED plants) in Barmer, Churu, Jhunjhunu, Nagaur, Bikaner, Jodhpur,
Bharatpur and Jaipur districts. Due to operational and maintenance problems,
difficulties are being felt to run these plants. The defence research Lab. Jodhpur has
developed indigenous ED plants for their own use and commissioned in Barmer district
for public. These ED plants can produce 30 cu.m/day of potable water (TDS 1500 mgl-1)

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from input salinity of 5000 mgl-1 TDS. Besides salinity this also removes other harmful
constituents like fluoride and nitrate.

         Saline ground water for irrigating salt tolerant crops is being used in Jalore,
Jodhpur, Pali, Alwar and Sikar districts where the soil is coarse textured and water table
is within 40 m. Farmers use saline water as life saving irrigation for kharif crops to make
up moisture deficiency and also for irrigating rabi crops, namely wheat, varieties
Kharchia-65, Kalyansona and Barley etc. As a management practice farmers divide their
holdings in four to five plots and irrigate only one plot in one season and keep it fallow
for one or more years so that salt enriched soil can be leached during rains. Brines and
highly saline ground water are being used to manufacture common salt and industrial
salts in part of Barmer, Jodhpur, Nagaur, Sikar, Jaipur and Bharatpur districts. With the
availability of fresh canal water supplies from IGNP, the conjuctive use of saline water
for irrigation is likely to increase.

         In Bikaner and Churu districts the soil is coarse textured sandy and deep. The
underground water has EC ranging from 2.0 to 6.0 dSm-1. In many cases the waters is
alkali. This water are being used to irrigate crops like groundnut, cluster bean, pearl
millet etc in kharif and mustard, wheat, cumin, fenugreek in rabi using sprinkler system
of irrigation.. However due to aridity of the region the soil tend to becomes saline the
use of such poor quality water for irrigation.

Periodic development of water level in state:
       Water level varies with rainfall, physiology, drainage and climatic condition. The
ground water condition in the state varies widely. To the East of Aravalies, depth of
water is comparatively shallower than in the West. It generally varies between 10 to
25m in the eastern part ,whereas, in the western part it ranges between 20 to 140m.
The water level slopes toward east and south- east on the eastern site, whereas to the
west of Aravalies, it slopes towards west and north-west. Shallow water level ( 7 to 26
m) have been noted in the canal command area of Ganganagar , Banswara, Kota and



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Bundi districts, whereas, deeper depth of water level has been observed in the western
districts of Rajasthan particularly in Jaisalmer, Bikaner, Barmer and Jodhpur.

       Ground water development is significantly high in eastern part of Rajasthan as
compared to the western part. The ground water recharge is relatively less in the
western Rajasthan , due to low and erratic rainfall, absence of ground water resources
and high evaporation . However, in some of the thick aquifers, the storage is many times
the annual recharge and hence, sustained pumpage can be achieved even during dry
spell.

       For evaluating trend of water level and long term fluctuation, year 1984 has
been considered as base year. The trend has been analysed between pre monsoon 1984
and pre monsoon ,1997 (Fig .7) on the basis of data collected from a network of 6700
Key wells in the state ground water department of Rajasthan                        (
Annonymous,2000)

       The state has been divided into 594 ground water potential zones. Out of these
322 zones fall in “white” category, where the ground water development is < 65 %, 71
zones fall in the “Grey “ category , having 65 to 85 % stage of development. The
remaining 201 zones has been categorized as “ Dark” zone, where stage of ground water
development is > 85%, out of these, 173 zone are over exploited , having a stage of
development > 100%.

       As per studies , out of 32 districts, 26 districts showed an average depletion of
water level and 6 districts showed marginal rise except certain pockets.The districts
which showed water level depletion are Ajmer, Alwar, Jaipur, Jalore, Jhunjhunu,
Jodhpur, Nagaur, Pali and Sirohi (Table 2.37)




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Fig 7. Water Level Fluctuation in Rajasthan



                      69
Table 2.37: District critically affected by water level depletion during 1984-2000


   S. No.        Districts    Av. drop (m)        S. No.     Districts    Av. Drop (m)


     1            Ajmer          (-)5.59            6        Jodhpur        (-) 6.60


     2            Alwar          (-)5.12            7         Nagaur        (-)6.50


     3            Jaipur         (-)5.74            8          Pali         (-)6.69


     4            Jalore         (-)8.00            9         Sirohi        (-)6.49


     5          Jhunjhunu        (-)6.22            -            -             -




        The prime reason for water level depletion is excessive withdrawl of water to
meet out the ever growing demand of agriculture, domestic and industrial purposes.The
sustainability of vagaries has further fallen prey to the unplanned development. Thus
due to shrinking of ground water resources, wells are getting dried up and chemical
quality of ground water is getting deteriorated.




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Description: Nature of salt affected soils and poor quality waters in Rajasthan