Groundwater Chemistry of Post Monsoon Season

Groundwater Chemistry of Post (2011) and Pre-Monsoon (2012) Season

In order to study the quality of groundwater (n=33) groundwater samples were

collected in post-monsoon season, 2011 from hand pump wells at shallow depth (18-

50ft) from Shah Bandar, KharoChann, K.T.Bandar, Ghora Bari and Mirpur Sakro. The

collected samples have been analyzed for different geochemical constituents using

standard method of analysis. The detail of the ionic constituents (Ca+2, Mg+2, Na+,

K+, Cl-, SO4-2) and non-ionic constituents (EC, pH,TDS) of the groundwater is

mentionin (Annex VII).

Classification of Groundwater Types in the Study Area

The quality of groundwater at any point below the surface reflects the

combined effects of many processes along the groundwater flow path. Chemical

reactions such as weathering, dissolution, precipitation, ion exchange and various

biological processes commonly take place below the surface. Hydrogeochemical

study is a useful tool to identify these processes that responsible for groundwater

chemistry (Jeevanadam et.al. 2007). Several authors have reported about the presence

of contaminants in soil (Muir & Baker, 1998; Wu, 1980) and water (Kolpin,

Barbash& Gillian, 1998) in various parts of the globe. In the management of the water

resources, quality of water is just as important as its quantity. In order to know the

quality and suitability of groundwater for domestic and irrigation purposes several

parameters based standard classification are available. Groundwater samples of the

study area have been discussed separately area wise according to the following

classification.

Classification of Groundwater Based on TDS

The total dissolved solids (TDS) estimated by residue on evaporation method.

Davis and De Wiest (2007) classified groundwater on the basis of TDS, If

groundwater have TDS value upto 500mg/l, it is considered desirable for drinking,

500-1000mg/l permissible for drinking and upto 3,000mg/l maximum permissible

limit and only useful for agriculture purpose (Table 21). While, according to WHO

(1984) TDS classification upto 500mg/l is highest and upto 1000 mg/l is permissible

desirable for drinking purpose (Table 21).

Table 21. Classification of groundwater based on TDS (Davis and De Wiest ,2007)

S.No TDSmg/l

Categories

1 500 desirable for drinking

2 500-1000 permissible for drinking

3 Upto 3,000 useful for agriculture

According to classification of groundwater based on TDS values, out of thirty three

water samples collected from Shah Bandar, Keti Bandar, Ghora Bari, Mirpur Sakro

and KharoChann Tehsil three groundwater samples found having TDS values upto

500mg/l, forteen samples shows TDS values within 500-1000mg/l and 16 water

samples found in the category of having TDS values more than 1000mg/l useful for

agriculture but not suitable for human consumption. The detail of water samples

Tehsil wise fall in different categories shown in (Table 22).

Table 22. Classification of groundwater based on TDS (Davis and De Wiest ,2007)

Categories Post-monsoon Pre-monsoon

Shah Bandar

Keti Bandar GhoraBari

Mirpur Sakro Kharo Chan Shah Bandar

Keti Bandar

desirable for drinking

Two samples(No. 1,4)

- - Two samples(No. 2,10)

-

permissible for drinking

- One sample (No.3) Three samples(No.2,4 6)

Eight samples (No. 1,4,7, 8,9,12,14,17 )

useful for agriculture

Three samples(No. 2,3,5)

Two samples(No. 1,2)

Three samples(No.1,3, 5)

Seven Samples (No. 3,4,6,11,13,16,17)

One sample (No.1)

Table.4 (a) Groundwater type in the study area based on TDS (post monsoon season, 2011)

S.No Categories Post-monsoon-2011 Total

Shah Bandar

Keti Bandar

1 desirable for drinking 2 -

2 permissible for drinking - 1

3 useful for agriculture 3 2

Table.4 (b) Groundwater type in the study area based on TDS (pre-monsoon, 2012)

S.No Categories Pre-monsoon-2012 Total

Shah Bandar


1 desirable for drinking 1 - -

2 permissible for drinking - - 2

3 useful for agriculture 1 1 5

Classification of Groundwater Based on EC and SAR

The quality of irrigation water in relation to the alkalinity hazard is expressed

by Sodium Adsorption Ratio (SAR). The agricultural yields are observed to be

generally low inlands irrigated with waters belonging to permissible to doubtful

category. This is probably due to the presence of sodium salts, which cause os-

moticeffects in soil plant system. While a high salt content (highEC)

inwaterleadstoformation ofsaline soil,highsodiumcontent (SAR)

leadstodevelopment of analkaline soil (N.JanardhanaRaju, 2007).

Thesodiumoralkalihazard inthe useofwater forirrigation isexpressed bydetermining

the

sodium adsorptionration (SAR) and it can be estimatedbytheformula

The groundwater facies classification based on EC and SAR (salinity categories) by

Gupta (1990) has been adopted in the present study to determine its suitability in term of

domestic agricultural purposes.The water from handpumpwells is of following type in the

study area (Table 22).

EcdS/m

Salinity Categories

< 2 Good water

> 2 Saline water

> 4 High saline water

Variable Alkali water

Table.4 (a) Groundwater type in the study area based on EC and SAR (post monsoon, 2011)

S.No Categories Post-monsoon-2011

Total

Shah Bandar


Mirpur Sakro

1 Good water 2 1 3 13

2 Saline water - - - 1

3 High saline water 2 - 2 3

4 Alkali water 1 2 1 1

Table.4 (b) Groundwater type in the study area based on EC and SAR (pre-monsoon, 2012)


Shah Bandar

Keti Bandar

1 Good water 1 -

2 Saline water 1

3 High saline water -

4 Alkali water 1 -

Classification of Groundwater Based on RSC

Residualsodium carbonate(RSC) has been calcu- latedto determinethe

hazardous effect ofcarbonate andbicarbonate onthequalityofwaterforagricultural

purpose(Eaton1950)andhasbeen determined bythe

formula:RSC=(CO3+HCO3)_(Ca+Mg). The US Salinity Laboratory Diagram

(1954) pro- posedthat waters containing more than 2.5 meq/l of RSC are not suited

forirrigation, whilethose having 1.25–2.5meq/l are marginally suitable and those

with less than 1.25meq/l are probably safe for irrigation. Following table is the

RSC based classification of the groundwater of the study (Table 24).

Table. RSC based Classification (The USSalinityLaboratory, 1954)S.No RSC Categories

1 < 1.25 Probably safe

2 1.25-2.5 Marginal Suitable

3 > 2.5 Un-suitable

Table.4 (a) Groundwater type in the study area based on RSC (post monsoon season, 2011)


Shah Bandar

Keti Bandar

1 Probably safe 1 2

2 Marginal Suitable 2 -

3 Un-suitable 2 1

Table.4 (b) Groundwater type in the study area based on RSC (pre-monsoon, 2012)

S.No Categories Pre-monsoon-2012

Shah Bandar

1 Probably safe 2 1

2 Marginal Suitable -

3 Un-suitable -

Classification of Groundwater Based on Na Content

Sodium concentration plays an important role in evaluating the groundwater

quality for irrigation because sodium causes an increase in the hardness of the soil as

well as reduction in its permeability (Tijani, 1994).Sodium content is usually

expressed in terms of percent sodium or soluble-sodium percentage (%Na). As per

the Indian standards, maximum of 60% sodium is permissible for irrigation water

(N.JanardhanaRaju 2007). (Wilcox 1955) classify groundwater on the basis of Na %

(Table 25).

Table 24. sodium percentage based Classification (Wilcox, 1955)

S.No Na% Categories

1 20 Excellent

2 21-40 Good

3 40-55 Poor

4 50-70 Very poor

Table 24. Classification of groundwater based on sodium percentage(Wilcox, 1955)

S.No Na% Categories Post-monsoon

Shah Bandar Keti Bandar Ghora Bari Mirpur Sakro

1 20 Excellent 4 1,3 2,5 1,2,5,6,8,14

2 21-40 Good 1,5 - 3,4,6 7,16

3 40-55 Poor 2,3 2 1 9,10,11,12,13,17,18

4 50-70 Very poor - - -

Table.4 (a) Groundwater type in the study area based on Na% (post monsoon season, 2011)


Shah Bandar

Keti Bandar

1 Excellent 1 2

2 Good 2 -

3 Poor 2 1

4 Very poor - -

Table.4 (b) Groundwater type in the study area based on Na% (pre-monsoon, 2012)

S.No Categories Pre-monsoon-2012

Shah Bandar

1 Excellent

2 Good

3 Poor

4 Very poor

In the light of the above classification, the chemical quality of groundwater (shallow

aquifers) has been discussed separately area wise and the groundwater facies has been

derived from piper triangular diagram.

Shah Bandar Tehsil Post Monsoon (2011)

Five groundwater samples were collected from Shah Bandar Tehsil in post

monsoon season, 2011. The pH of groundwater samples ranges from 7.05-7.78 (Table

….) with an average of 7.48. All samples have pH value more than 7 indicating

alkaline nature of the samples. According to WHO (1984) TDS specification, 40%

and 60% of groundwater samples belongs to highest desirable and maximum

permissible limits respectively. While, Davis and De Weist (2007) TDS based

classification, indicate that out of five groundwater samples one (no. 4) is desirable,

one (no. 1) is permissible and remaining three (no. 2, 3, 5) are only suitable for

agricultural purpose.

According to EC and SAR based classification by Gupta (1990), two of these

samples (1, 4) belong to good water category as their EC and SAR values are <2

(0.69, 0.86 dS/m) and <10 (2.0, 2.39) respectively. The Ca and Mg contents are more

than Na and Cl in these two samples, suggesting their fresh water facies. While, two

samples (3, 5) are in high saline water category as their EC and SAR values are 4.01,

4.06dS/m and 23.3, 30.38 respectively. In these two samples increased EC also leads

to increased concentration of Na and Cl, which indicates the impact of sea water

intrusion in the area. On the other hand remaining one sample (2) belongs to high

saline water category as its SAR and calcium plus magnesium values are same

(18.19). It indicates that fresh water is being replaced by salt water (Table 26).

Table 25.Physico-chemical analyses of groundwater samples (post monsoon, 2011)

from Shah Bandar

S. No

EC dS/m

TDS

pH Anions Meq/l

CationsMeq/l

Na/Cl

ratio

Ca/Mgrati

o

Cl/HCO3Ratio

SAR

RSC

CO3

HCO3

Cl SO4

Ca+Mg

Na K

1 0.857

548 7.51 Nil 3.2 2.1 1.62 4.805

3.69 0.81 10.86

0.65 2.39 -1.61 CaHCO3

2 3.630

232 7.78 Nil 11 20.1 4.17 18.19

30 0.512 0.41 1.8 18.19

-7.19 NaCl

3 4.01 2566

7.63 Nil 6.6 30.0 4.58 9.87 51.73

0.512 0.57 4.5 23.3 -3.27 NaCl

4 0.696

445 7.43 Nil 4.8 1.78 0.94 5.62 3.39 0.10 2.97 0.37 2.02 -0.82 CaHCO3

5 4.06 2598

7.05 Nil 7.4 28.6 6.04 5.502

50.43

1.282 0.62 3.8 30.38

2.38 NaCl

According to U.S salinity laboratory (1954) RSC based classification it is

observed that one sample (no. 4) is probably safe, two samples (no. 1, 5) are marginal

suitable while remaining two sample (no. 2, 3) have RSC value greater than 2.5 are

not suitable even for agriculture (Table classification wala). According to Wilcox

(1955) sodium content based classification, one sample (no. 4) belongs to excellent

water category indicate that it is probably safe for irrigation, two samples (no. 1, 5)

and two (no. 2, 3) belongs to good and poor water category respectively. Good water

category is safe for irrigation but poor is hazardous and indicating the saline water

intrusion. On the same content base Raju (2007), sodium content value of all samples

is less than 60% indicate the suitability of groundwater for irrigation.

Cat ion chemistry of Shah Bandar groundwater samples indicating the

increasing of parameters like Na>Ca>Mg>K. Sodium is showing good co-relation

with chloride (r = 1.0) indicating that these have been derived from same source. If

halite dissolution is responsible for sodium, Na/Cl ratio should be approximately

equal to 1, whereas ratio greater than 1 is typically interpreted as Na released from

silicate weathering reaction (Meyback, 1987). In present study, Na/Cl ratio of

groundwater samples generally varying from 1.49 - 1.1.98 (Fig. 3) suggesting silicate

weathering.

Calcium and magnesium concentration of Shah Bandar groundwater have low

co-relation and coefficient (0.023) indicating the absence of carbonatic source.

Further, Ca/Mg ratios of the most of the groundwater samples range from 0. 41 to

10.8 indicating the dolomite contribute solutes to the groundwater.

Fig.3 Na/Cl ratio suggests silicate weathering .

The concentration of chloride indicates that salt water intrusion and irrigation

return flow might be responsible ( Luscynski and Swarzenski 1996). This is also

supported by the Cl/HCO3. Generally a ratio more than 2.8 indicates severe

contamination with sea water (Ragunath, 1982). Ggroundwater samples collected

from Shah Bandar area reveal Cl/HCO3ratio of 0.37 – 4.5 indicating that some

groundwater samples are safe from sea water intrusion but some are affected.

Piper trilinear diagram (Fig.4) of Shah Bandar for geochemical classification

and hydrochemical processes of groundwater for post monsoon season indicates that

most of the waters are Na-Cl type. It suggesting the influence of sea water, ancient

saline groundwaters, or dissolution of halite (NaCl). Such water type create salinity

both in irrigation and domestic uses (Raju, 2007) For irrigation purpose it is very

high in salinity hazard and free from RSC but Mg hazard is 72.5 mg/l which is

another indicator of saline water intrusion. In this area most serious threat to the

groundwater is intrusion of saline water to fresh water. While, remaining samples are

Ca-HCO3type typical occurrence of this facie in aquifer is shallow, fresh groundwater

in recharge area. It is suggesting irrigation return flow and anthropogenic activities

(Jeevanandamet.al., 2007). Such water type have temporary hardness (Raju,2007).

Cations Anions

Fig. 4: Piper diagram for hydrochemicalfacies of groundwater (post monsoon, 2011)of Shah Bandar

Keti Bandar Tehsil Post Monsoon (2011)

Three groundwater samples were collected from Keti BandarTehsil in post

monsoon season, 2011. The pH of groundwater samples ranges from 6.01 - 7.58

(Table ….) with an average of 6.78. Almost samples have pH value 7 indicating

alkaline nature of the samples. According to WHO (1984) TDS specification, 33%

and 66% of groundwater samples belongs to highest desirable and maximum

permissible limits respectively. While, Davis and De Weist (2007) TDS based

classification, indicate that out of three groundwater samples one (no. 3) is desirable

and remaining two (no. 1, 2) have high TDS value and only suitable for agricultural

purpose.

According to EC and SAR based classification by Gupta (1990), two of these

groundwater samples (1, 2) are within alkali water category as their EC (3.55,

3.74dS/m and SAR (27.9, 15.48)values are variable. In these samples Na contents are

higher than the total contents of Ca plus Mg, which shows the impact of sea water

intrusion. The loss of Na and gain of Ca and Mg suggests a direct

cation exchange usually observed in similar situations when the

seawater is replacing fresh water (Appelo and Postma, 2005;

Cardona et al., 2004; De Montety et al., 2008; Yaouti et al., 2009).

While, the remaining sample (3) belongs to good water category, as its EC and

SAR values are <2 (1.009dS/m) and <10 (2.41) respectively. Further, its calcium plus

magnesium contents are also higher than Na and Cl (Table27). The good water quality

water of this hand pump well may be due to its location near canal or fresh water

pond in the area.

Table 26Physico-chemical analyses of groundwater samples (post monsoon, 2011)from K.T.Bandar

S. No.

EC dS/m

TDS

pH Anions Meq/l

CationsMeq/l

Na/Cl

ratio

Ca/Mgrati

o

Cl/HCO3Ratio

SAR

RSC

Water

Type

CO3

HCO3

Cl SO4

Ca+Mg

Na K

1 3.55 2272

7.58 Nil 6.8 26.8 2.92 6.05 48.69

1.03 1.8 2.0 3.9 27.9 0.75 NaCl

2 3.74 2394

6.75 Nil 9.4 24.4 4.16 15.49

43.04

0.512

1.8 1.1 2.5 15.48

-6.09 NaCl

3 1.009

646 6.01 Nil 5.5 3.6 1.54 6.02 4.17 0.15 1.2 2.7 0.6 2.41 -0.42 CaCl


observed that two samples (no. 1,3) are probably safe and only one sample (no. 2)

have RSC value greater than 2.5 and not suitable even for agricultural purpose (Table

classification wala). According to Wilcox (1955) sodium content based classification,

two samples (no. 1,3) belongs to excellent water category indicate that it is probably

safe for irrigation. While, remaining one sample (no. 2) belong to poor water category

and it is hazardous and indicating the saline water intrusion. On the same content

base classification Raju (2007), sodium content value of all samples is less than 60%

indicate the suitability of groundwater for irrigation.

Cat ion chemistry of Keti Bandargroundwater samples indicating the


with chloride (r = 1.0) indicating that these have been derived from same source. If

halite dissolution is responsible for sodium, Na/Cl ratio should be approximately

equal to 1, whereas ratio greater than 1 is typically interpreted as Na released from

silicate weathering reaction (Meyback, 1987). In present study, Na/Cl ratio of

groundwater samples generally varying from 1.49 - 1.1.98 (Fig.5) suggesting silicate

weathering.


Calcium and magnesium concentration in groundwater of Keti Bandarvary

from 4.4 – 8.0 and 1.6 – 7.5 with an average of concentrations of 6.3 and 4.1 (Table

27). They have low co-relation and coefficient (0.55) among the major ions indicating

the absence of carbonatic source. Further, Ca/Mg ratios of the groundwater samples

range from 0. 6 to 3.9 indicating the dolomite contribute solutes to the groundwater

(Kannanet.al., 2007). Potassium concentarion in groundwater varies from 0.15 – 1.03

meq/l with an average of 0.56 meq/l (Table 26). Potassium present in the water might

have come from irrigation return flow.

The choloride- bicarbonate ratio is a good factor to identify saltwater

intrusion. Chloride is the dominant ion of sea water it is only available in small

quantities in groundwater (Ragunath, 1990). On the other hand, bicarbonate eis the

dominant ion in groundwater whereas, its concentration in saltwater is very small.

According to (Ragunath, 1990) Cl/HCO3ratio = 2.8 is a threshold value for saltwater

intrusion. So, one sample (no. 1) value exceeding from 2.8 indicating it is

contaminated by saltwater intrusion. While remaining two (no. 2,3) have low value

and safe from intrusion impact.

Piper trilinear diagram (Fig.6) of Shah Bandar for geochemical classification


most of the waters are Na-Cl type. It suggesting the influence of sea water, ancient

saline groundwaters, or dissolution of halite (NaCl). Such water type create salinity

both in irrigation and domestic uses (Raju, 2007) For irrigation purpose it is very

high in salinity hazard and free from RSC but Mg hazard is 72.5 mg/l which is

another indicator of saline water intrusion. In this area most serious threat to the

groundwater is intrusion of saline water to fresh water. While, remaining samples are

Ca-HCO3type typical occurrence of this facie in aquifer is shallow, fresh groundwater

in recharge area. It is suggesting irrigation return flow and anthropogenic activities

(Jeevanandamet.al., 2007). Such water type have temporary hardness (Raju,2007).

Cations Anions

Fig. 6: Piper diagram for hydrochemicalfacies of groundwater(post monsoon, 2011)of Keti Bandar

4.2.4Ghora Bari Tehsil Post Monsoon (2011)

Six groundwater samples were collected from Ghora Bari Tehsil in post


(Table 28) with an average of 7.15. Almost samples have pH value 7 indicating

alkaline nature of the samples. According to WHO (1984) TDS specification, half of

groundwater samples belong to highest desirable and half to maximum permissible

limits. While, Davis and De Weist (2007) TDS based classification, indicate that out

of six groundwater samples three samples (no. 2,4,6) are desirable and remaining

three (no. 1, 3,5) are only suitable for agricultural purpose.

According to EC and SAR based classification by Gupta (1990), two

groundwater samples (2, 4,) from this area belong to good water category, as their EC

and SAR values are<2 (1.531, 1.063 dS/m) and <10 (5.76 to 2.05) respectively. While

one sample (3) belongs to saline water category (EC : 1.921 dS/m, SAR: 5.16). On the

other hand, two samples (1, 5) are highly saline, as their EC are >4 (10.05, 3.92 dS/m)

and SAR >10 (39.7, 25.17 ) respectively. In these samples, sodium, chloride and

sulphate contents are higher than total calcium plus magnesium contents. Only one

sample (6) belongs to alkali water type (EC 1.30 and SAR 34.0), which indicates

sever impact of sea water intrusion (Table 27).

Table 27.Physico-chemical analyses of groundwater samples (post monsoon, 2011)from Ghora Bari and Kharo Chan

S. No

EC dS/m

TDS

pH Anions Meq/l

CationsMeq/l

Na/Cl

ratio

Ca/Mgrati

o

Cl/HCO3rati

o

Na %

SAR

RSC

Water Type

CO3

HCO3

Cl SO4

Ca+Mg

Na K

1 10.05

6432

6.881

Nil 11.6

9.193

10 14.5

106.08

1.025

11.5

2.2 0.79

88 39.7

-2.92 NaH-SO4

2 1.531

980 7.66

Nil 8.6 6.79

1.66

7.45

11.130

1.179

1.63

0.46

0.78

62 5.76

1.15 NaH-CO3

3 1.921

1229

6.91

Nil 8 10.18

2.2 9.85

11.47

0.358

1.12

2.0 1.27

55 5.16

-1.85 NaCl

4 1.063

680 6.69

Nil 5.6 3.78

1.98

8.03

4.1 0.205

1.0 2.1 0.675

35 2.05

-2.43 CaH-CO3

5 3.920

2509

7.48

Nil 7.2 28.39

2.92

8.19

50.86

1.03

1.79

0.70

3.9 86 25.2

-0.99 NaCl

6 1.30

832 7.65

Nil 7.8 3.58

2.71

5.44

56.08

6.15

15.6

0.67

0.45

92 34.0

2.36 NaH-CO3

1 3.76

2406

6.81

Nil 7.2 26.99

3.33

16.1

37.39

0.76

1.3 3.7 13.2

-8.8

Only one groundwater sample was collected from KharoChann Tehsil. Its EC

and SAR values are 3.76 dS/m and 13.21 respectively. It belongs to alkali water

facies of the groundwater indicating the salt water intrusion in the area (Table 27).

According to U.S salinity laboratory (1954) RSC based classification, it is

observed that two samples (no. 2,5) are probably safe, three sample (no. 3,4,6) have

RSC value in limit (1.25 - 2.5) are marginal suitable and only one sample (no. 1) have

RSC value greater than 2.5 not suitable for agricultural purpose (Table classification

wala). According to Wilcox (1955) sodium content based classification, one samples

(no. 4) belongs to good water category indicate that it is safe for irrigation, one

sample (no. 3) belong to poor water category, While remaining samples (no. 1,2,5,6)

belong to very poor water category and it is hazardous and indicating the saline water

intrusion. On the same content base classification Raju (2007), sodium content value

of two samples (no. 2, 3) is less than 60% indicate the suitability of groundwater for

irrigation and remaining all have higher value.



with chloride (r = 0.195) indicating that these have been derived from different

source. In present study, Na/Cl ratio of groundwater samples generally varying from

1.0 – 15.6 (Fig.7) suggesting silicate weathering.

Fig. 7 Na/Cl ratio suggests silicate weathering .



28). They have low co-relation and coefficient (0.019) among the major ions

indicating the absence of carbonatic source. Further, Ca/Mg ratios of the groundwater

samples range from 0.46 – 2.2indicating the dolomite contribute solutes to the

groundwater (Kannanet.al., 2007). Potassium concentarion in groundwater varies

from 0.15 – 1.03 meq/l with an average of 0.56 meq/l (Table 28). Potassium present in

the water might have come from irrigation return flow.



quantities in groundwater (Ragunath, 1990). On the other hand, bicarbonate is the



intrusion. So, no sample have Cl/HCO3ratio greater than 2.8 indicating safe

groundwater from saline water intrusion.

Piper trilinear diagram (Fig.8) of Ghora Bari for geochemical classification

and hydrochemical processes of groundwater for post monsoon season indicates two

groundwater samples (no. 3, 5) are Na-Cl type. It suggesting the influence of sea

water, ancient saline groundwaters, or dissolution of halite (NaCl). Such water type

create salinity both in irrigation and domestic uses (Raju, 2007) For irrigation

purpose it is very high in salinity hazard . Two (no. 2, 6) are Na-HCO3 type have high

hazardous impact for irrigation, one sample is Ca-HCO3type typical occurrence of

this facie in aquifer is shallow, fresh groundwater in recharge area. It is suggesting

irrigation return flow and anthropogenic activities (Jeevanandamet.al., 2007). Such

water type has temporary hardness (Raju, 2007). While, remaining one (no. 1) is Na-

SO4this is rare type, can result from mixing of ancient Na-rich groundwaters with

pyritr oxidation waters, also formed by intensive evaporation of waters which

havepreviously lost their Ca and HCO3.

Cations Anions

Fig. 8: Piper diagram for hydrochemicalfacies of groundwater (post monsoon, 2011)of Ghora Bari

4.2.5MirpurSakro Tehsil Post Monsoon (2011)

Eighteen groundwater samples were collected from Mirpur SakroTehsil in

post monsoon season, 2011. The pH of groundwater samples ranges from 6.77 - 7.58

(Table 29) with an average of 7.18. Mostly samples have pH value more than 7

indicating alkaline nature of the samples. According to WHO (1984) TDS

specification, 61% and 38% of groundwater samples belongs to highest desirable and

maximum permissible limits respectively. While, Davis and De Weist (2007) TDS

based classification, indicate that out of eighteen groundwater samples two (no. 2, 15)

are desirable, eight (no. 1, 5, 7, 8, 9, 12, 14, 18) are permissible and remaining are not

suitable for agricultural purpose.

SAR based classification by Gupta (1990), twelve

(1,2,3,5,7,8,9,10,11,12,14,15) samples belong to good water category, as their EC and

SAR values are <2 dS/m and <10 respectively. While, four samples (6, 13, 17, 18)

having variable EC and SAR fall in alkali water category. On the other hand, sample

(16) is saline water, as its EC is >2 ( 2.17dS/m) and SAR is <10 (8.0 ) and the

remaining sample (4) is high saline water with its EC (>4) 4.19 dS/m and SAR (>10)

21.36 respectively.

Most of the groundwater samples from this area are non – saline, only four

water samples are moderately to severe saline, as their EC and SAR are relatively

higher as compared to other samples. In all these samples sodium, chloride and

sulphate ions show positive correlation. It indicates the presence of sodium chloride

salt along with sodium sulphate salt in these four samples. High concentration of

sodium and chloride in these samples indicates saltwater intrusion. The increased

concentration and positive correlation of chloride and sulphate also suggests sea

water intrusion in the area (Table 29).


observed that six samples (no. 1,2,5,6,8,14) are probably safe, two samples (no. 7,16)

are marginal suitable while, remaining sample (no. 9,10,11,12,13,17,18) have RSC

value greater than 2.5and they are not suitable even for agriculture (Table

classification wala). According to Wilcox (1955) sodium content based classification,

six samples (no. 1,2,5,6,8,14) belongs to excellent water category indicate that it is

probably safe for irrigation, two samples (no. 7,16)) ) belongs to good and

remaining (no. 9,10,11,12,13,17,18) belongs to poor water category. Good water

category is safe for irrigation but poor is hazardous and indicating the saline water

intrusion. On the same content base Raju (2007), sodium content value of all samples

is less than 60% indicate the suitability of groundwater for irrigation.

Cat ion chemistry of Mirpur Sakrogroundwater samples indicating the

increasing trend of parameters like Na>Ca>Mg>K. The sodium concentration in the

area ranges from 2.13 – 67.82 meq/l with an average concentration of 15.18 meq/l

(Table 29). Sodium is not showing good co-relation with chloride (r = 0.097)

indicating that these have been derived from different source. In present study, Na/Cl

ratio of groundwater samples generally varying from 0.13 – 10.8, while only one

sample have very high Na/Cl ratio (374.6) (Fig.9). Na/Cl ratio of five groundwater

samples is equal to 1, indicating the dissolution of halite, While remaining all samples

have ratio greater than 1 indicating sililcateweathering suggesting silicate weathering

(Meyback, 1987). It is also well supported by high values of HCO3than sodium

(Kannana, 2007). In some samples HCO3have low value than sodium so, sodium

might have come from irrigation return flow and anthropogenic activity.


Calcium and magnesium concentration of Mirpur Sakrogroundwater vary

from 2.4 – 9.6 and 1.0 – 8.3 meq/l with an average concentration of 4.45 and 2.9

meq/l respectively(Table 29).They have low co-relation and coefficient (0.115)

among the major ions indicating the absence of ubiquitous source of Ca and Mg

(Kannana,2007). Further, Ca/Mg ratios of the most of the groundwater samples range

from 0. 7 to 4.15 indicating the dolomite contribute solutes to the groundwater.

Potassium concentration in groundwater varies from 0.15 – 1.03 meq/l with an

average of 0.56 meq/l (Table 29). According to (Ragunath, 1990), Cl/HCO3ratio of all

groundwater samplea is less than threshold value (2.8) indiv=cating this area is safe

from seawater intrusion. Only two samples (no. 4, 7) have high Cl/HCO3ratio

indicating saline water intrusion and in same both samples Cl value is also high. The

concentration of Clinidicate that saltwater iintrusion and irrigation return flow might

be responsible (Luscznski&Swarzenski, 1996).

Table 28Physico-chemical analyses of groundwater samples(post monsoon, 2011)from Mirpur Sakro

S.

EC

TD

pH

An

CationsMeq/l Na/Clratio

Ca/Mgrati

o

Cl/HCO3

ratio

SAR

RSC

Water Typ

eCO

HCO3 Cl SO4

Ca+Mg

Na K

1 0.

59

7.

Ni

6 1.19 2.514

6.23

3.86

0.102

3.23

0.94

0.19

2.19

-0.23

NaH-CO3

2 0.

43

7.

Ni

4.6 1.58 1.041

3.614

3.52

0.20

2.2 1.98

0.34

2.63

0.986

NaH-CO3

3 1.

10

6.

Ni

5.6 8.35 3.58

12.63

8.869

0.20

1.0 3.16

1.49

3.53

-7.03

CaCl

4 4.

26

7.

Ni

8.2 26.98 8.54

15.1

58.69

1.282

2.1 0.819

3.2 21.36

-6.9 NaCl

5 0.

58

7.

Ni

5.8 2.48 1.812

6.02

3.78

0.179

1.5 2.30

0.42

2.18

-0.22

CaH-CO3

6 1.

11

7.

Ni

7.6 0.18 4.08

6.64

67.82

0.153

3746

0.72

0.02

37.26

0.96

NaH-CO3

7 0.

58

7.

Ni

6 35.46 1.416

4.01

4.95

0.102

0.13

2.88

5.91

3.49

1.99

NaCl

8 0.

52

7.

Ni

4.2 2.40 1.75

5.212

3.347

0.102

1.3 4.15

0.57

1.28

-1.01

CaH-CO3

9 0.

60

6.

Ni

4.2 3.89 1.604

7.03

3.869

0.128

0.99

1.67

0.92

2.06

-2.82

CaCl

10

0.

54

7.

Ni

4 2.68 1.916

23.44

3.43

0.102

1.2 2.4 0.66

1.0 -19.44

CaH-CO3

11

1.

10

7.

Ni

8.6 7.78 0.666

5.43

12.34

0.7 1.5 1.23

0.90

7.52

-3.17

NaH-CO3

12

1.

72

7.

Ni

5.6 0.39 2.229

9.027

4.26

0.128

10.8

3.05

0.07

2 -3.427

NaCl

13

2.

17

7.

Ni

9.6 12.4 5.937

5.02

35.69

0.384

2.8 1.25

1.29

22.56

4.58

NaCl

14

1.

89

6.

Ni

6.6 4.88 3.166

7.63

9.30

0.153

1.9 1.90

0.73

4.77

-1.03

NaH-CO3

15

0.

43

7.

Ni

4 1.9 1.2 5.42

2.13

0.102

1.12

2.8 0.47

1.29

-1.42

CaH-CO3

16

2.

13

7.

Ni

9.2 8.48 3.58

7.83

15.91

0.30

1.8 2.2 0.92

8 1.37

NaH-CO3

17

3.

20

7.

Ni

8.4 17.39 5.83

12.47

37.82

1.03

2.1 0.66

2.0 15.18

-4.07

NaCl

18

1.

79

7.

Ni

5 4.88 2 7.65

5.13

0.15

1.0 0.98

0.97

10.05

-2.65

NaCl

Piper trilinear diagram (Fig.10) of Mirpur Sakrofor geochemical classification


six groundwater samples are waters are Na-HCO3 type. It is hazardous for irrigation.

Five groundwater samples are Na-Cl type. It suggesting the influence of sea water,

ancient saline groundwaters, or dissolution of halite (NaCl). Such water type creates

salinity both in irrigation and domestic uses (Raju, 2007). For irrigation purpose it is

very high in salinity hazard. In this area most serious threat to the groundwater is

intrusion of saline water to fresh water. While, four samples are Ca-HCO3type typical

occurrence of this facie in aquifer is shallow, fresh groundwater in recharge area. It is

suggesting irrigation return flow and anthropogenic activities

(Jeevanandamet.al.,2007). Such water type have temporary hardness (Raju,2007) and

three samples are Ca-Cl type. It is associated with the invasion of shallow, fresh

aquifers by sea water, less commonly form by dissolution of the very rare evaporate

mineral tachydrite (Cacl2). Its also have high salinity hazardous for irrigation.

Cations Anions

Fig. 9: Piper diagram for hydrochemicalfacies of groundwater (post monsoon, 2011) of Mirpur Sakro

Ground Water Chemistry of Pre-Monsoon Season

The quality of 28 groundwater samples collected from hand pump wells at

shallow depth (18- 50ft) from Shah Bandar, KharoChann, K.T.Bandar, Ghora Bari

and Mirpur Sakro have been analysed for various physico-chemical parameters

(Table 13). Classified as above based on EC and SAR (Gupta, 1994).

Shah Bandar and Keti Bandar Tehsil Pre Monsoon (2012)

Two groundwater samples were collected from Shah Bandar Tehsil in pre

monsoon season of 2011. The EC, TDS and pH values of groundwater samples are

(2.79 and 0.671), (1786 and 427) and (7.12 and 7.13) respectively (Table 30).

According to WHO (1984), TDS specification one sample belong to poor water

category while one is excellent. On the basis of EC and SAR classification, one

sample belong to alkali water category, while remaining one fall in good water

category.

Table 30.Physico-chemical analyses of groundwater samples from Shah Bandar and Keti Bandar

S. No

EC dS/m

TDS pH Anions Meq/l

CationsMeq

/l

Na/Cl

ratio

Ca/Mgrati

o

Cl/HCO3

Ratio

SAR

RSC

Water Typ

e

CO3

HCO3

Cl SO4 Ca+Mg

Na K

1 2.79 1786

7.12 - 7.2 26.0 2.5 3.3 42.1 0.35 1.619

0.65 3.61 23.17

0.6 NaCl

2 0.671

427 7.13 - 4.2 2.2 1.52 2.125

3.69 0.164

1.68 2.4 0.52 2.53 0.5 NaHCO3

1 2.5 1600

6.96 - 7.8 20.58

1.770

6.73 19.0 0.38 0.92 0.75 2.6 7.32 5.66

Ghora Bari Tehsil Pre Monsoon (2012)

Seven groundwater samples were collected from Ghora Bari Tehsil in pre-


(Table 31) with an average of 7.38. Almost samples have pH value 7 indicating

alkaline nature of the samples. According to WHO (1984) TDS specification, three

groundwater samples (no. 2,4,6) belong to highest desirable and remaining all belong

to maximum permissible limits. While, Davis and De Weist (2007) TDS based

classification, indicate that out of six groundwater samples three samples (no. 2,4,6)

are desirable and remaining four (no. 1, 3,5) are only suitable for agricultural

purpose.

According to EC and SAR based classification by Gupta (1990), two

groundwater samples (2, 4,) from this area belong to good water category, as their EC

and SAR values are<2 (1.531, 1.063 dS/m) and <10 (5.76 to 2.05) respectively. While

one sample (3) belongs to saline water category (EC : 1.921 dS/m, SAR: 5.16). On the

other hand, two samples (1, 5) are highly saline, as their EC are >4 (10.05, 3.92 dS/m)

and SAR >10 (39.7, 25.17) respectively. In these samples, sodium, chloride and

sulphate contents are higher than total calcium plus magnesium contents. Only one

sample (6) belongs to alkali water type (EC 1.30 and SAR 34.0), which indicates

sever impact of sea water intrusion (Table 31).

Table 31Physico-chemical analyses of groundwater samples (pre monsoon, 2012)from Ghora Bari

S. No

EC dS/m

TDS

pH Anions Meq/l

CationsMeq/l

Na/Cl

ratio

Ca/Mgrati

o

Cl/HCO3rati

o

Na %

SAR

RSC

Water Type

CO3 HCO3

Cl SO4

Ca+Mg

Na K

1 5.14

3290

7.63

- 12.0

76.98

4.08

5.15

94 1.24

1.22

0.87

6.42

95 40.8

3.12 Nacl

2 1.152

737 7.40

- 8.4 5.69

0.958

2.705

95 0.63

16.70

0.59

0.68

75 4.65

2.99 NaH-CO3

3 1.598

1022

7.03

- 9.4 9.39

1.16

4.93

64 0.312

6.82

1.12

1.0 64 3.91

0.46 Nacl

4 0.882

564 7.0 - 4.6 3.18

1.45

2.905

61 0.212

19.18

1.41

0.69

61 7.0 1.21 NaH-CO3

5 2.73

1747

7.79

- 7.0 49.2

1.68

3.0 93 0.53

1.89

0.5 7.02

93 7.79

1 Nacl

6 1.182

756 7.70

- 8.6 3.49

1.54

1.6 85 0.57

24.35

0.6 0.41

85 7.70

5.4 NaH-CO3

1 1.677

1073

7.15

- 6.8 10.88

2.125

3.505

78 0.52

7.169

0.590

1.6 78 7.15

0.21 H-Cl

According to U.S salinity laboratory (1954) RSC based classification, it is

observed that two samples (no. 2,5) are probably safe, three sample (no. 3,4,6) have

RSC value in limit (1.25 - 2.5) are marginal suitable and only one sample (no. 1) have

RSC value greater than 2.5 not suitable for agricultural purpose (Table classification

wala). According to Wilcox (1955) sodium content based classification, one samples

(no. 4) belongs to good water category indicate that it is safe for irrigation, one

sample (no. 3) belong to poor water category, While remaining samples (no. 1,2,5,6)

belong to very poor water category and it is hazardous and indicating the saline water

intrusion. On the same content base classification Raju (2007), sodium content value

of two samples (no. 2, 3) is less than 60% indicate the suitability of groundwater for

irrigation and remaining all have higher value.



with chloride (r = 0.195) indicating that these have been derived from different

source. In present study, Na/Cl ratio of groundwater samples generally varying from

1.0 – 15.6 (Fig ….) suggesting silicate weathering.

Fig. 10 Na/Cl ratio suggests silicate weathering



…). They have low co-relation and coefficient (0.019) among the major ions

indicating the absence of carbonaticsource. Further, Ca/Mg ratios of the groundwater

samples range from 0.46 – 2.2indicating the dolomite contribute solutes to the

groundwater (Kannanet.al., 2007). Potassium concentarion in groundwater varies

from 0.15 – 1.03 meq/l with an average of 0.56 meq/l (Table …). Potassium present in

the water might have come from irrigation return flow.



quantities in groundwater (Ragunath, 1990). On the other hand, bicarbonate is the



intrusion. So, no sample have Cl/HCO3ratio greater than 2.8 indicating safe

groundwater from saline water intrusion.

Piper trilinear diagram (Fig.1) of Ghora Bari for geochemical classification

and hydrochemical processes of groundwater for post monsoon season indicates two

groundwater samples (no. 3, 5) are Na-Cl type. It suggesting the influence of sea

water, ancient saline groundwaters, or dissolution of halite (NaCl). Such water type

create salinity both in irrigation and domestic uses (Raju, 2007) For irrigation

purpose it is very high in salinity hazard . Two (no. 2, 6) are Na-HCO3 type have high

hazardous impact for irrigation, one sample is Ca-HCO3type typical occurrence of

this facie in aquifer is shallow, fresh groundwater in recharge area. It is suggesting

irrigation return flow and anthropogenic activities (Jeevanandamet.al., 2007). Such

water type have temporary hardness (Raju,2007). While, remaining one (no. 1) is Na-

SO4this is rare type, can result from mixing of ancient Na-rich groundwaters with

pyritr oxidation waters, also formed by intensive evaporation of waters which

havepreviously lost their Ca and HCO3.

Cations Anions

Fig. 11: Piper diagram for hydrochemicalfacies of groundwater of Ghora Bari (pre-monsoon)

MirpurSakro Tehsil Pre Monsoon (2012)

Eighteen groundwater samples were collected from Mirpur SakroTehsil in

post monsoon season, 2011. The pH of groundwater samples ranges from 6.77 - 7.58

(Table ….) with an average of 7.18. Mostly samples have pH value more than 7

indicating alkaline nature of the samples. According to WHO (1984) TDS

specification, 61% and 38% of groundwater samples belongs to highest desirable and

maximum permissible limits respectively. While, Davis and De Weist (2007) TDS

based classification, indicate that out of eighteen groundwater samples two (no. 2, 15)

are desirable, eight (no. 1, 5, 7, 8, 9, 12, 14, 18) are permissible and remaining are not

suitable for agricultural purpose.

SAR based classification by Gupta (1990), twelve

(1,2,3,5,7,8,9,10,11,12,14,15) samples belong to good water category, as their EC and

SAR values are <2 dS/m and <10 respectively. While, four samples (6, 13, 17, 18)

having variable EC and SAR fall in alkali water category. On the other hand, sample

(16) is saline water, as its EC is >2 ( 2.17dS/m) and SAR is <10 (8.0 ) and the

remaining sample (4) is high saline water with its EC (>4) 4.19 dS/m and SAR (>10)

21.36 respectively.

Most of the groundwater samples from this area are non – saline, only four

water samples are moderately to severe saline, as their EC and SAR are relatively

higher as compared to other samples. In all these samples sodium, chloride and

sulphate ions show positive correlation. It indicates the presence of sodium chloride

salt along with sodium sulphate salt in these four samples. High concentration of

sodium and chloride in these samples indicates saltwater intrusion. The increased

concentration and positive correlation of chloride and sulphate also suggests sea

water intrusion in the area (Table 18).


observed that six samples (no. 1,2,5,6,8,14) are probably safe, two samples (no. 7,16)

are marginal suitable while, remaining sample (no. 9,10,11,12,13,17,18) have RSC

value greater than 2.5and they are not suitable even for agriculture (Table

classification wala).

According to Wilcox (1955) sodium content based classification, six samples

(no. 1,2,5,6,8,14) belongs to excellent water category indicate that it is probably safe

for irrigation, two samples (no. 7,16)) ) belongs to good and remaining (no.

9,10,11,12,13,17,18) belongs to poor water category. Good water category is safe for

irrigation but poor is hazardous and indicating the saline water intrusion. On the same

content base Raju (2007), sodium content value of all samples is less than 60%

indicate the suitability of groundwater for irrigation.

Cat ion chemistry of Mirpur Sakrogroundwater samples indicating the

increasing trend of parameters like Na>Ca>Mg>K. The sodium concentration in the

area ranges from 2.13 – 67.82 meq/l with an average concentration of 15.18 meq/l

(Table…). Sodium is not showing good co-relation with chloride (r = 0.097)

indicating that these have been derived from different source. In present study, Na/Cl

ratio of groundwater samples generally varying from 0.13 – 10.8, while only one

sample have very high Na/Cl ratio (374.6) (Fig ….). Na/Cl ratio of five groundwater

samples is equal to 1, indicating the dissolution of halite, While remaining all samples

have ratio greater than 1 indicating sililcateweathering suggesting silicate weathering

(Meyback, 1987). It is also well supported by high values of HCO3than sodium

(Kannana, 2007). In some samples HCO3have low value than sodium so, sodium

might have come from irrigation return flow and anthropogenic activity.

Fig. 12 Na/Cl ratio suggests silicate weathering .

Calcium and magnesium concentration of Mirpur Sakrogroundwater vary

from 2.4 – 9.6 and 1.0 – 8.3 meq/l with an average concentration of 4.45 and 2.9

meq/l respectively(Table 32).They have low co-relation and coefficient (0.115)

among the major ions indicating the absence of ubiquitous source of Ca and Mg

(Kannana,2007). Further, Ca/Mg ratios of the most of the groundwater samples range

from 0. 7 to 4.15 indicating the dolomite contribute solutes to the groundwater.

Potassium concentration in groundwater varies from 0.15 – 1.03 meq/l with an

average of 0.56 meq/l (Table 32). Potassium present in the water might have come

from irrigation return flow.

According to (Ragunath, 1990), Cl/HCO3ratio of all groundwater samplea is

less than threshold value (2.8) indiv=cating this area is safe from seawater intrusion.

Only two samples (no. 4, 7) have high Cl/HCO3ratio indicating saline water intrusion

and in same both samples Cl value is also high. The concentration of Clinidicate that

saltwater iintrusion and irrigation return flow might be responsible

(Luscznski&Swarzenski, 1996).

Table32Physico-chemical analyses of groundwater samples from Mirpur Sakro (pre monsoon, 2012)

S. No

EC dS/m

TD pH Anions Meq/l

CationsMeq/l

Na/Cl

ratio

Ca/Mgrati

o

Cl/HCO3rati

o

SAR

RSC

Water Typ

e

CO3

HCO3

Cl SO4

Ca+M

g

Na K

1 0.923

485 6.69

Nil 6.2 1.41

0.104

3.98

3.52

0.20

2.5 1.52

0.23

2.49

2.22

NaH-CO3

2 0.681

740

7.10

Nil 6.6 4.59

1.91

6.8 6.39

0.15

1.4 1.43

0.70

1.87

-0.2 NaH-CO3

3 1.70

1026

6.81

Nil 7.2 8.68

2.16

12.2

6.86

0.2 0.79

1.44

1.21

2.77

-5 Ca-Cl

4 4.19

1766

7.16

Nil 8.0 1.80

3.75

11.2

32.6

0.52

18.1

0.6 0.23

13.7

-3.2 NaH-CO3

5 0.911

570 7.24

Nil 7.8 3.186

1.43

5.83

4.34

0.23

1.36

1.75

0.41

1.0 1.97

NaH-CO3

6 1.745

972

7.58

Nil 9.8 5.38

2.13

5.03

14.6

0.148

2.71

1.65

0.55

9.20

4.77

NaH-CO3

7 0.907

497

7.19

Nil 6.4 2.11

0.91

4.18

4.69

0.133

2.22

1.64

0.33

3.2 2.22

NaH-CO3

8 0.814

451

7.30

Nil 4.0 2.19

1.16

4.83

3.60

0.12

1.64

0.94

0.55

2.31

-0.83

NaH-CO3

9 0.946

571

7.10

Nil 8.8 2.0 0.79

6.6 4.13

0.13

2.07

1.0 0.227

2.27

2.2 NaH-CO

310 0.8

442054

6.95

Nil 7.0 26.0

6.14

10.7

60.4

0.27

2.32

1.0 3.71

26.11

-3.7 Na-Cl

11 1.607

888

7.32

Nil 9.0 18.61

2.33

9.8 18.86

0.28

1.01

1.04

2.07

8.52

-0.8 Na-Cl

12 1.132

1465

7.11

Nil 5.6 18.61

2.3 9.8 18.8

0.28

1.01

1.04

3.32

8.4 -4.2 Na-Cl

13 2.670

1388

7.31

Nil 10.8

11.19

3.20

4.41

5.86

0.10

0.52

0.83

1.04

3.27

1.19

Na-Cl

14 1.4 708

6.97

Nil 7.6 3.60

1.58

6.41

5.86

0.10

1.63

1.66

0.47

3.27

1.19

NaH-CO3

15 0.686

440

7.16

Nil 5.4 18.8

0.66

5.38

2.91

0.135

0.16

2.41

3.48

1.77

0.02

Ca-Cl

16 2.17

1155

7.14

Nil 11.0

0.99

1.958

5.8 16.17

0.266

16.33

0.93

0.09

9.49

5.2 NaH-CO3

17 3.130

1542

6.92

Nil 10.0

16.18

3.25

10.85

19.0

0.51

1.17

0.74

1.62

8.15

-0.85

Na-Cl

18 1.242

1027

6.92

Nil 11.8

8.0 1.18

8.51

9.47

0.246

1.18

1.18

0.68

4.59

3.29

NaH-CO3

Piper trilinear diagram (Fig.1) of Mirpur Sakrofor geochemical classification


six groundwater samples are waters are Na-HCO3 type. It is hazardous for irrigation.

Five groundwater samples are Na-Cl type. It suggesting the influence of sea water,

ancient saline groundwaters, or dissolution of halite (NaCl). Such water type creates

salinity both in irrigation and domestic uses (Raju, 2007). For irrigation purpose it is

very high in salinity hazard. In this area most serious threat to the groundwater is

intrusion of saline water to fresh water. While, four samples are Ca-HCO3type typical

occurrence of this facie in aquifer is shallow, fresh groundwater in recharge area. It is

suggesting irrigation return flow and anthropogenic activities (Jeevanandamet.al.,

2007). Such water type have temporary hardness (Raju,2007) and three samples are

Ca-Cl type. It is associated with the invasion of shallow, fresh aquifers by sea water,

less commonly form by dissolution of the very rare evaporate mineral tachydrite

(Cacl2). Its also have high salinity hazardous for irrigation.

Cations Anions

Fig. 13: Piper diagram for hydrochemicalfacies of groundwater of Mirpur Sakro

PROBLEMS IDENTIFIED

Excessive amount of sodium were found in irrigation which promote soil

dispersion and structural breakdown.

Due to excessive sodium water supply to the crop is difficult and production is

reducing.

Excess soil salinity in the stud area causes poor and spotty stands of crops,

uneven and stunted growth and poor yields, the extent depending on the

degree of salinity.

Same nala’s were identified in the study area, mixed with flood water and

somewhere with sea water which increasing soil salinity.

Irrigation water is available only for four months due to which area is

suffering from shortage of irrigation water.

Land was affected by flood water because water was kept staying for four

months, which lead caused waterlogging and leaching of subsurface salt to the

surface.

Because of poor drainage system flood water remains stagnant and precipitate

both black and white salts on the soil surface by evaporation.

Because of fuderal system canal water is being stolen by power full people.

When they fulfill water requirement to their fields then leave it.

In some fields water evaporated naturally, because owner of the adjacent

agricultural fields did not allow water to drain same nala.

Some areas were also affected by tidal waves.

To mitigate the menace of rising groundwater and the associated problem of

waterlogging and salinity, a network of drainage canal was constructed with in

the Indus Basin to drain groundwater directly to the Arabian sea. The drainage

system has been less effective dur to low gradient of flat topography and has

in fact resulted in the intrusion of seawater to about 80 km upstream (Panhwar,

1999).

The increase in salinity due to depleting of fresh water contribution by the

Indus River has reduced the suitability of the delta for the cultivation of red

rice, the production of the exoctic fruit, and raising of livestock (Inam.et.al.,

2007).

The mangrove ecosystem is being degraded, and the mangroves are now

virtually monospecific and comparatively stunted with losses of about 2% year

-1 (Inam.et.al. 2007).Comparison Between Post (2011) and Pre-Monsoon (2012) Groundwater Water

Samples of Shah Bandar Tehsil

Five groundwater samples were collected from Shah Bandar Tehsil in post

monsoon and two in pre-monsoon, Based on analytical results, the chemical indices

derived from hydro geochemical parameters of post and pre monsoon groundwater

samples of shah Bandar are presented in (Table 17). Piper rectangular diagram for

geochemical classification and hydro chemical processes of groundwater for both

seasons indicates that most of water is Na-Cl type.

Total dissolved solids of Shah Bandar groundwater ranges from 445mg/l to

2598mg/l with a mean of 1576 mg/l and from 429 to 1786 mg/l with a mean of 1107

mg/l for post monsoon and pre monsoon respectively. From the analytical results, post

monsoon groundwater has higher TDS value as compare to pre monsoon. The

increase of TDS in post monsoon seasons is on the higher side than the pre monsoon

season due to mixing of surface pollutants during the infiltration and percolation of

rainwater (N. Janardhana 2007). Davis and De Wiest (1966) TDS based classification,

it is observed that out of 5 groundwater samples of post monsoon 1 is desirable for

drinking, 2 are permissible for drinking. While, remaining 2 samples and 2 samples of

pre monsoon are not desirable and permissible for drinking but suitable for

agricultural purpose. The salinity (with respect to total dissolved solids) of

groundwater affects the growth of plants directly and also affects soil structure,

permeability and aeration, which indirectly affect plant growth (Mohan, Singh,

Tripathi and Choudhary, 2000).

The Electrical Conductivity (EC) ranges from 0.696 to 4.06dS/m with a mean

of 2.650 dS/m and 0.671 to 2.79 dS/m with a mean of 1.730 dS/m for post monsoon

and pre monsoon respectively. Gupta (1990) classified ground waters on the basis of

EC and SAR. According to this classification, sample no 1, 4 and 2 are belong to good

water category, sample no. 2 and 1 are belong alkali water category, sample no 3 and

5 belong to high saline water category for post monsoon and pre monsoon

respectively.

Table 33.Physico-chemical analyses of groundwater samples from Shah Bandar in post and pre monsoon

SNo.

Grid

N

E

l

e

T

o

t

p

H

P

e

r

S

o

d

R

e

sPo

Pr

Po

Pr

Po

Pr

Po

Pr

Po

Pr

Po

Pr

Po

Pr

1 (5

-0.

54

7.48

2. -2 (5

-3.

23 7.

63 18 -3 (

5(5 4. 2.

25 7. 7.

84 93 23 23 - 0.4 (

5(5 0. 0.

44 7. 7.

38 64 2. 2. - -5 (

5-

4.25 7.

90 30 2.

SNo.

Water

H

C

C

l

S

O

C

a

N

a

K

Po

Pr

Po

Pr

Po

Pr

Po

Pr

Po

Pr

Po

Pr

Po

Pr

1 C

-3. 2. 1. 4. 48 3.

2Na

-11 20 4. 18 63 303

Na 6. 7. 30 26 4. 2. 9. 3. 84 93 51 0.4Ca 4. 4. 1. 2. 0. 1. 5. 2. 38 64 3. 0.5Na 7. 28 6. 5. 90 50

Sodium concentration is important in classifying irrigation water because

sodium reacts with soil to reduce its permeability. Sodium content is usually

expressed in terms of percent sodium or soluble- sodium percent Na%. As per the

Indian standards, max.of 60% sodium is permissible for irrigation water. Sample no 1

and 4 of post monsoon have sodium content less than 60% while, remaining all

samples of post monsoon have high sodium content. Two groundwater samples from

same grid (56, 55) have high sodium content in pre monsoon as compare to post

monsoon season.

As per the Richards (1954) SAR based classification, two samples (1,4) and

1(2) of post monsoon and pre monsoon respectively are in excellent category, because

none of the sample exceed the value SAR=10 (Table ). While, three samples (2, 3, 5)

and 1(1) of post and pre monsoon respectively are in poor condition. From the

residual sodium carbonate (RSC) values of the Shah Bandar area, it is observed that

out of 5 post-monsoon water samples, 1 is safe, 2 are marginal and 2 are not suitable

for irrigation. But out of 2 pre-monsoon water samples, both are safe for irrigation.

From these analyses, it is found that sample no 3 in post monsoon season was rich in

carbonate and not suitable for irrigation but in pre-monsoon it is suitable irrigation.

Comparison Between Post (2011) and Pre-Monsoon (2012) Groundwater Water Samples of K.T.Bandar Tehsil

Three groundwater samples were collected from K.T Bandar Tehsil in post

monsoon and only one in pre-monsoon from same grid 49, Based on analytical

results, the chemical indices derived from hydro geochemical parameters of post and

pre monsoon groundwater samples of K.T Bandarare presented in (Table 18). Piper

rectangular diagram for geochemical classification and hydro chemical processes of

groundwater for both seasons indicates that most of water is Na-Cl type. It is

hazardous for irrigation purpose. While, one sample of 49 grid was Ca-SO4 type in

post monsoon and in pre monsoon it is converted into Na-Cl water type. It indicates

saline water intrusion.

Total dissolved solids (TDS) of K.T Bandargroundwater ranges from 646mg/l

to 2394mg/l with a mean of 1770 mg/l and 1600 for post and pre-mon soon

respectively. From the analytical results, post monsoon groundwater has higher TDS

value. Pre monsoonal groundwater has higher TDS values (1600 mg/l) as compare to

its post monsoon samples value (646 mg/l). Davis and De Wiest (1966), TDS based

groundwater classification it is observed that out of 3 groundwater samples of post

monsoon one (3) is permissible for drinking, while remaining two samples (1, 2 and

one samples of pre-monsoon are suitable for agriculture purpose.

Table 34.Physico-chemical analyses of groundwater samples from K.T.Bandarin post and pre monsoon

SNo.

Grid

N

E

l

e

T

o

t

p

H

P

e

r

S

o

d

R

e

sPo

Pr

Po

Pr

Po

Pr

Po

Pr

Po

Pr

Po

Pr

Po

Pr

1 (5

-0.

54

7.48

2. -2 (5

-3.

23 7.

63 18 -3 (

4(4 4. 2.

25 7. 7.

84 93 23 23 - 0.

SNo.

Water

H

C

C

l

S

O

C

a

N

a

K

Po

Pr

Po

Pr

Po

Pr

Po

Pr

Po

Pr

Po

Pr

Po

Pr

1 Na

-3. 2. 1. 4. 89 3.2 N

a-

11 20 4. 18 74 303 Ca 6. 7. 30 26 4. 2. 9. 3. 42 74 51 0.

The Electrical Conductivity (EC) ranges from 1.009 to 3.74 dS/m with a

mean of 2.77 dS/m and only one sample having EC value 2.5 dS/m of post monsoon

and pre-monsoon respectively. According to Gupta (1990) EC and SAR based

classification, sample no 3 of post monsoon belong to good water category and

sample no 1 and 2 belong to variable category it shows that it is alkali water. While,

one sample of pre-moonsoon belong to saline water category.According to Wilcox

(1955) sodium content based classification, it is observed that only one sample of post

monsoon groundwater is poor while remaining 2 sample and one of pre monsoon are very

poor because their sodium content is higher than 60% and as well as higher than 50-70%

limit range.

As per the Richards (1954) SAR based classification, one each sample (3) of

post monsoon and pre monsoon belong to excellent groundwater category because

their SAR values are <10 and it is safe for agricultural. While sample no 1 and 2 of

post monsoon have SAR >10 this limit is not suitable for agriculture. From the US

salinity laboratory (1954) the residual sodium carbonate (RSC) based classification, it

is observed that out 3 post-monsoon water samples, 2 samples (1,3) are probably safe

and 1 sample (2) is unsuitable for irrigation. While remaining 1 sample (2) and one

sample of pre-monsoon are unsuitable for irrigation.

Comparison Between Post (2011) and Pre-Monsoon (2012) Groundwater Water Samples of Ghora Bari Tehsil

Six and seven groundwater samples were collected from Ghora BariTehsil

during post and pre-monsoon respectively.Based on analytical results, the chemical

indices derived from hydro geochemical parameters of post and pre monsoon

groundwater samples of Ghora Bariare presented in (Table 35). Piper rectangular

diagram for geochemical classification and hydro chemical processes of groundwater

for both seasons indicates that most of water samples are NaH-CO3type.

Total dissolved solids of Ghora Barigroundwater ranges from 680mg/l to

6432mg/l with a mean of 2110 mg/l and from 564 to 3290 mg/l with a mean of

1326mg/l for post monsoon and pre monsoon respectively. From the analytical

results, post monsoon groundwater has higher TDS value as compare to pre monsoon.

The increase of TDS in post monsoon seasons is on the higher side than the pre

monsoon season due to mixing of surface pollutants during the infiltration and

percolation of rainwater (N. Janardhana 2007). According to Davis and De Wiest

(1966), it is observed that out of 6 groundwater samples of post monsoon 3 (2,4,6) are

permissible for drinking and remaining 3 (1,3,5 ) are suitable for agriculture purpose.

While, on the other hand out of 7 groundwater samples of pre-monsoon 3 (2,4,6) are

permissible for drinking and remaining 4 (1,3,5,7) are suitable for agriculture.

The Electrical Conductivity (EC) ranges from 1.063 to 10.05 dS/m with a

mean of 3.3 dS/m and 0.882 to 5.14 dS/m with a mean of 2.05 dS/m for post monsoon


EC and SAR. According to this classification, three samples (2,3,4) and five

(2,3,4,6,7) belongs to good water category, two samples (1,5) and (1), while one each

sample (6) and (5) belongs to alkali water category for post monsoon and pre

monsoon respectively.

Table 35.Physico-chemical analyses of groundwater samples from Ghora Bariin post and pre monsoon

SNo.

Grid

N

E

l

e

T

o

t

p

H

P

e

r

S

o

d

R

e

sPo

Pr

Po

Pr

Po

Pr

Po

Pr

Po

Pr

Po

Pr

Po

Pr

1 (3

(3

10 5.54

6. 7.48

39 40 - 3.2 (3

(3 1. 1.

23 7. 7.

63 5. 4. 1. 2.3 (

3(3 1. 1.

25 6. 7.

84 93 5. 3. - -4 (

4(4 1. 0.

44 6. 7.

38 64 2. 7. - -5 (

4(4 3. 2.

25 7. 7.

90 25 7. - 16 (

4(4 1. 1. 7. 7. 34 7. 2. 5.7 (4 1. 7. 7. -

SNo.

Water

H

C

C

l

S

O

C

a

N

a

K

Po

Pr

Po

Pr

Po

Pr

Po

Pr

Po

Pr

Po

Pr

Po

Pr

1Na N 11 12 9. 76 10 4. 14 5. 88 94 1. 1.2Na Na 8. 8. 6. 5. 1. 0. 7. 2. 62 95 1. 0.

3Na N 8 9. 10 9. 2. 1. 9. 4. 55 64 0. 0.4Ca Na 5. 4. 3. 3. 1. 1. 8. 2. 35 61 0. 0.5Na N 7. 7. 28 49 2. 1. 8. 3. 86 93 1. 0.6Na Na 7. 8. 3. 3. 2. 1. 5. 1. 92 85 6. 0.7

H- 6. 10 2. 3. 78 0.

On the basis of sodium content of the groundwater, one each sample (4) and

(3) of post-monsoon belongs to good and poor water category respectively, While

remaining all samples of both seasons are very poor because, their sodium content

values are exceeding to 60% which is hazardous for agriculture. As per US salinity

laboratory (1954), the residual sodium carbonate (RSC) based classification, it is

observed that out 3 post-monsoon water samples, 2 samples (1,3) are probably safe

and 1 sample (2) is unsuitable for irrigation. While remaining 1 sample (2) and one

sample of pre-monsoon are unsuitable for irrigation.

Comparison Between Post (2011) and Pre-Monsoon (2012) Groundwater Water Samples of MirpurSakro Tehsil

Eighteen of each groundwater samples were collected from Mirpur

SakroTehsil in post monsoon and two in pre-monsoon season, Based on analytical

results, the chemical indices derived from hydro geochemical parameters of post and

pre monsoon groundwater samples of Mirpur Sakro are presented in (Table 20). Piper

rectangular diagram for geochemical classification and hydro chemical processes of

groundwater for both seasons indicates that most of water are of post monsoon are

Na-HCO3 and Na-Cl type and few are Ca-HCO3 and Ca-Cl type. When we compare

this water type to the pre monsoon groundwater sample type it indicate most of the

groundwater sample (11) are Na-HCO3 in nature and same in quantity (5) are Na-Cl

in nature while , two are Ca-Cl type. It indicates the replacement of Cl ions by HCO3

ions and Na ions by Ca ions.

Total dissolved solids of Mirpur Sakrogroundwater ranges from 436mg/l to

2003mg/l with a mean of ----mg/l and from 451 to 1766 mg/l with a mean of …… for

post monsoon and pre monsoon respectively. From the analytical results, post

monsoon groundwater has higher TDS value as compare to pre monsoon. The

increase of TDS in post monsoon seasons is on the higher side than the pre monsoon

season due to mixing of surface pollutants during the infiltration and percolation of

rainwater (N. Janardhana 2007). Davis and De Wiest (1966) TDS based classification,

it is observed that out of 18 groundwater samples of post monsoon 2 (1,15) are

desirable for drinking, 7 (1,4,7,8,9,14,18) are permissible for drinking. While,

remaining are suitable for agriculture. On the other hand out of 18 groundwater

sample of pre monsoon 4 (1,7,8,15) are desirable for drinking, 6 (2,5,6,9,11,14,) are

permissible for drinking purpose while remaining are good for irrigation.

The Electrical Conductivity (EC) ranges from 0.696 to 4.06dS/m with a mean

of 2.650 dS/m and 0.671 to 2.79 dS/m with a mean of 1.730 dS/m for post monsoon


EC and SAR. According to this classification, sample no 1, 4 and 2 are belong to good

water category, sample no. 2 and 1 are belong alkali water category, sample no 3 and

5 belong to high saline water category for post monsoon and pre monsoon

respectively.

Table 36.Physico-chemical analyses of groundwater samples from MirpurSakroin post and pre monsoon

SNo.

Grid

N

E

l

e

T

o

t

p

H

P

e

r

S

o

d

R

e

sPo

Pr

Po

Pr

Po

Pr

Po

Pr

Po

Pr

Po

Pr

Po

Pr

114 14 0. 0.6

59

48 7. 6.6

39

48 2. 2.4 - 2.22

13 13 0. 1.143

74 7. 7.1

50

49 2. 1.8 0. -3

11 11 1. 1.610

10 6. 6.8

41 36 3. 2.7 - -54

3 3 4. 2.726

17 7. 7.1

79 60 21 13. - -5

4 4 0. 0.858

57 7. 7.2

40

44 2. 1.0 - 1.96

20 20 1. 1.511

97 7. 7.5

91

75 37 9.2 0. 4.77

19 19 0. 0.758

49 7. 7.1

55

54 3. 3.2 1. 2.28

17 17 0. 0.752

45 7. 7.3

40

43 1. 2.3 - -9

24 24 0. 0.860

57 6. 7.1

36

39 2. 2.2 - 2.21

0 26 26 0. 3.254

20 7. 6.9

13

85 1. 26. - -1

1 27 27 1. 1.310

88 7. 7.3

71

66 7. 8.5 - -1

2 35 35 1. 2.272

14 7. 7.1

32

66 2 8.4 - -1

3 34 34 2. 2.117

13 7. 7.3

88

57 22 3.2 4. 1.11

4 33 33 1. 1.189

70 6. 6.9

55

48 4. 3.2 - 1.11

5 39 39 0. 0.643

44 7. 7.1

29

36 1. 1.7 - 0.01

6 28 28 2. 1.813

11 7. 7.1

67

74 8 9.4 1. 5.21

7 38 38 3. 2.420

15 7. 6.9

75

64 15 8.1 - -1

8 40 40 1. 1.679

1027 7. 6.9

40

53 10 4.5 - 3.2

S. No.

Water

H

C

C

l

S

O

C

a

N

a

K

Po

Pr

Po

Pr

Po

Pr

Po

Pr

Po

Pr

Po

Pr

Po

Pr

1Na Na 6 6. 1. 1. 2. 0. 6. 3. 3. 3. 0. 0.

2Na Na 4. 6. 1. 4. 1. 1. 3. 6. 3. 6. 0. 0.3Ca Ca 5. 7. 8. 8. 3. 2. 12 12 8. 6. 0. 0.4Na Na 8. 8. 26 1. 8. 3. 15 11 58 32 1. 0.5Ca Na 5. 7. 2. 3. 1. 1. 6. 5. 3. 4. 0. 0.6Na Na 7. 9. 0. 5. 4. 2. 6. 5. 67 14 0. 0.7Na Na 6 6. 35 2. 1. 0. 4. 4. 4. 4. 0. 0.8Ca Na 4. 4. 2. 2. 1. 1. 5. 4. 3. 3. 0. 0.9Ca Na 4. 8. 3. 2. 1. 0. 7. 6. 3. 4. 0. 0.1

0 Ca N 4 7. 2. 26 1. 6. 23 10 3. 60 0. 0.11 Na N 8. 9. 7. 18 0. 2. 5. 9. 12 18 0. 0.12 Na N 5. 5. 0. 18 2. 2. 9. 9. 4. 18 0. 0.13 Na N 9. 10 12 11 5. 3. 5. 4. 35 5. 0. 0.14 Na Na 6. 7. 4. 3. 3. 1. 7. 6. 9. 5. 0. 0.15 Ca Ca 4 5. 1. 18 1. 0. 5. 5. 2. 2. 0. 0.16 Na Na 9. 11 8. 0. 3. 1. 7. 5. 15 16 0. 0.17 Na N 8. 10 17 16 5. 3. 12 10 37 19 1. 0.18 Na

Na 5 11 4. 8. 2 1. 7. 8. 5. 9. 0. 0.

Sodium concentration is important in classifying irrigation water because

sodium reacts with soil to reduce its permeability. Sodium content is usually

expressed in terms of percent sodium or soluble- sodium percent Na%. As per the

Indian standards, max.of 60% sodium is permissible for irrigation water. Sample no 1

and 4 of post monsoon have sodium content less than 60% while, remaining all

samples of post monsoon have high sodium content. Two groundwater samples from

same grid (56, 55) have high sodium content in pre monsoon as compare to post

monsoon season.

Cations Anions

Fig. 14: Piper diagram for hydrochemicalfacies of groundwater of Mir purSakro

Documents

Groundwater Chemistry of Post Monsoon Season