Sarhad J. Agric. Vol.24, No.1, 2008

EFFECT OF TUBE ON WATER LOGGING AND SALINITY IN KAFUR DHERI UNIT PESHAWAR

Syed Mohammad Bilal and Tahir Sarwar

ABSTRACT Research study was conducted at Kafur Dheri Unit, Peshawar during 2002 to find the effect of tube well drainage on water logging, salinity and sodicity. Discharge of 18 tube was determined by volumetric method. depth at 11 locations was measured with the help of electric water level indicator. Auger-hole method was used to determine at 8 locations in the research area. Soil and water samples collected from 25 locations were analyzed for electrical conductivity (EC), pH, sodium adsorption ratio (SAR) and residual sodium carbonate (RSC) and were compared with soil and water quality standards adopted by WAPDA. Discharge of tube wells ranged from 7.95 to 54.52 l s -1, with overall average of 32.37 l s -1. Generally, the actual discharges of tube wells were lower (6 to 53%) than their design discharges. Also 53% tube wells were out of order. The water table depth ranged from 0.14 to 0.84 m from the ground surface with an average of 0.41 m. In waterlogged areas mostly water table was very shallow and caused a severe problem for crops, however, water table was deep where natural drains were passing nearby or where tube wells were working properly for a long time. Dominant soil texture in the area was loam and clay loam, and hydraulic conductivity ranged from 1.03 to 3.54 m/day with an average of 1.53 m/day. Results showed that the salinity is not the major problem in the area. Generally, electrical conductivity of the soil and water was in the range of 0.30 to 2.80 and 0.36 to 1.28 dS m -1, respectively. Soil and water of Kafur Dheri Unit are moderately alkaline in nature with pH ranging from 7.59 to 8.26 and 7.45 to 8.83, respectively. SAR of soil and water ranged from 0.10 to 1.02 and 0.13 to 3.15, respectively. There was no residual sodium carbonate in soil and water samples. It is concluded from the study that water logging is still the major problem of the area; hence, rehabilitation of existing drainage system is necessary.

Keywords: water logging, salinity, tube well drainage, SAR, hydraulic conductivity

INTRODUCTION Water logging is one of the major problems of infiltration and root penetration. Average salinity Pakistan’s agriculture. Over , runoff water values at Surizai, Kafur Dheri and Swabi SCARP had from higher to lower areas, seepage from canals and 0.19, 2.46 and 1.53 dS m -1 respectively (Anwar, reservoirs and poor irrigation practices have resulted 2000; Khan et al , 2000; Asim, 1999). Soil pH has in wide spread problems of water logging and much to do with the solubility of various compounds salinity. To overcome water logging problem, and the suitability of soil conditions to microbial drainage of surplus water is required from root zone activity. The values of pH found at Surizai, Kafur of the crop. Wet soil conditions are generally Dheri and Swabi SCARP were 8.15, 8.65 and 8.76, accompanied by oxygen deficiency. This deficiency respectively (Anwar, 2000; Khan et al , 2000; Asim, causes reduction in plant survival and continued poor 1999). Sodium Adsorption Ratio (SAR) is the criteria aeration results in death of cells, decrease in cell to measure the sodium hazard of water, as SAR permeability or even death of roots. Excess water increase the sodium hazard of water also increases from root zone can be drained out through surface, (Asim, 1999). subsurface pipe drainage or vertical (tube wells) drains. Tube wells are used for both drainage as well Chaudhry et al. (2000) studied the bio-drainage as irrigation, and help in maintaining a balance water through certain categories of plants, which were table beneath the root zone if properly managed. tolerant to water logging and salinity. Annual water use by the plantation ranged from 300 – 2100 mm. Hydraulic conductivity is directly linked with soil Khan et al. (2000) studied the soil nutrient status, fertility and porosity. A good drainage system textural classes, salinity and alkalinity level of Kafur increases soil fertility and porosity, which enable Dheri SCARP Area. Most of the textural class in plant residues and plant roots penetration into the Kafur Dheri is clay loam and textures are grouped as soil, which ultimately increases the hydraulic 27% sand, 37.3% silt and 35.7% clay. Malik and conductivity. Wooldridge (1997) studied a comprehensive program of Salinity Control and Reclamation Projects The use of saline water may result in the reduction of (SCARPs) launched in the Indus basin, Pakistan in crop yields, while sodic water reduces pore space in 1959. They found that the SCARP performance fell soil; which ultimately reduces soil air and soil water, short of targets due to a decline in tube well pumpage creates hard pan and causes high problems to water due to deficiency in the maintenance. Knops et al.

Department of Water Management, NWFP Agricultural University, Peshawar – Pakistan

Syed Mohammad Bilal, et al. Effect of tube well drainage on water logging and salinity …… 50

(1996) reviewed the performance of drainage systems Water Table Depth Measurement in Pakistan and showed that the installed tube well Water table depth of 11 tube wells at 3 locations each and pipe drainage systems may led to improved soil (close to tube well, 50 m and 100 m away from the salinity if users give their share in operation and tube well) was measured with the help of an electrical maintenance of the system. Wolters et al. (1996) water level indicator and averages were calculated. reported the relationship between drainage technology and effluent quality, a tube well drainage Determination of Hydraulic Conductivity system (SCARP II) and a pipe drainage system Hydraulic conductivity was determined by auger-hole (Fourth Drainage Project) are compared. Whereas the method at eight different locations in Kafur Dheri effluent quality of tube well systems either remained Unit. Typical ranges of hydraulic conductivity for constant or deteriorated, the effluent of pipe drainage different soil texture are given in Table I. systems showed improvement. Soil and Water Sampling and Analysis Peshawar SCARP was started in 1973 aiming to drain Soil and water samples (25 each) were collected from water from Peshawar, Kafur Dheri and Pabbi areas. selected locations. Soil samples were collected with Kafur Dheri has a Gross Command Area (GCA) of the help of soil auger from 0 – 30 cm layer. The 12,158 ha and Culturable Command Area (CCA) of collected samples were taken to the laboratory in 8289 ha. About 15% area is out of cultivation plastic bags and were oven dried. After drying, the completely and 45% area (1822 ha) is partial samples were crushed and passed through 2-mm productive. About 5228 ha out of 12158 ha has water sieve and stored for analysis. The water samples were depth from 0 – 5 ft. Total numbers of tube wells collected in glass bottles from selected tube wells. installed were 64 with a discharge of 2.90 The soil and water samples were analyzed for cusecscumecs. But presently about 48 tube wells are electrical conductivity, pH, sodium adsorption ratio working with a discharge of 1.50 cumecs.cusecs. The (SAR) and residual sodium carbonate (RSC). main cause of water logging is the lack of operation and maintenance (O&M) and encroachment of drains Electrical conductivity of the soil extract (ECe) was by villagers, which leads to the flooding of determined with the help of digital conductivity surrounding areas. In 1989 about 80% area was non- meter (Model 4310, Jenway, UK). The pH of the soil saline, 15% was slightly, 4% was moderately and 1% suspension was determined by using the pH meter was strongly saline (NDP, 2000). (InloLab, WTW, Germany). Suspension was made at the ratio of 1:5 (1 soil and 5 water). Sodium ion The present study was conducted at Kafur Dheri, concentration was determined by Flame Photometer Peshawar during 2002 to compare the actual and (Model 410, Sherwood Scientifics Ltd. UK). Calcium design discharges of tube wells, present status of and magnesium were found by Atomic Absorption water logging, salinity, and hydraulic conductivity of Spectrophotometer (AAnalyst 200, Perkin Elmer, the research area. USA).

MATERIALS AND METHODS Soil and Water Quality Standards Site Description The researchers have used different limits for EC, Kafur Dheri is located in district Peshawar of NWFP. SAR and RSC for soil and water classification for It lies between latitudes 34.00 0 to 34.16 0 N and agriculture use. The different parametric limits longitudes 71.38 0 to 71.51 0 E. It covers a part of adopted by WAPDA (1974) Pakistan, for the District Peshawar and adjoining tribal area of Khyber classification of soil and water into different classes Agency. The area is bounded by Jue-Sheikh Civil are given in Tables II and III, respectively. Canal in the North and East, Warsak Gravity Canal (West), Warsak Minor (North-west) and Palosi RESULTS AND DISCUSSION Khwar in Southeast. Peshawar, the provincial capital Comparison of Actual and Design Discharge lies close to South-eastern boundary of the area. Table IV presents comparison of actual discharge of selected tube wells in Kafur Dheri unit with their Tube Well Discharge Measurement design discharges. Minimum and maximum values of Discharge of 18 tube wells was measured in Kafur actual discharges of tube wells were 7.59 and 54.52 l Dheri unit. Volumetric method was used for s-1 at Tube well No. 33 and 25, respectively, with an measurement of tube well discharges. The discharge overall average of 32.37 l s -1. Generally, the actual of a tube well was measured in the tank that existed discharges of tube wells were lower (6 to 53%) than in front of it. their design discharges. Lower actual discharges may be due to wear and tear of pumps and well screens.

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Partly, it may also be attributed to the drought predominantly loam, silt loam, clay loam, sandy loam condition of the past few years, which has resulted in and clay. Generally, sandy soils have higher the decline in recharge rate to . hydraulic conductivity as compared to silty and Reduction in the discharges of tube well has clayey soils. Hydraulic conductivity range 0.5 to 2.0 increased the severity of water logging problem in the m/day is generally for loam, clay loam and clay (well area. It was confirmed during the field data collection structured), and most of the Kafur Dheri soils fall in also, that in those areas where the tube wells had not this range. Hydraulic conductivity range 1 – 5 m/day been in operation for a long time due to some reasons is generally for medium sand and soil of tube well (faults in the tube well or generator etc.), the water No. 13 falls in this class of hydraulic conductivity. table was much higher compared to adjoining areas. Hydraulic conductivity can be increased by Tube wells in Kafur Dheri area have remained the improving soil structure and pore size distribution. key source of water table control. However, due to Soil structure and pore size distribution can be excessive wear and tear of these wells, the intensity improved through green manure and farmyard of water logging problem in the area has increased. manure. Microorganisms decompose green manure Higher operation and maintenance cost of tube wells and farmyard manure to organic matter which is also a constraint to their continuous operation. In improves soil structure and pore size distribution that order to combat the problem, design and installation ease the movement of water within soil. Crop roots of sustainable and environment friendly drainage also increase hydraulic conductivity by improving system is the future need of the area. structure and increasing macrospores (Qureshi and Barrett, 1998). Thus, it is expected that hydraulic Water Table Depth conductivity of the research area may further Figure. 1 shows the average water table depth at 11 increases if water table is lowered by improving the locations in waterlogged area of Kafur Dheri Unit. existing drainage system or installing other efficient The minimum and maximum values of water table drainage system. depth were 0.14 and 0.85 m from the ground surface at Tube wells No. 17 and 12, respectively. Average Salinity water table for the waterlogged area was 0.41 m from Table V shows the electrical conductivity of soil the ground surface. Generally, in waterlogged areas samples collected from Kafur Dheri Unit. Minimum water table was very shallow and caused a severe and maximum electrical conductivity values were reduction in crop yield. Results of the study showed 0.30 and 2.80 dS m -1 at Tube wells No. 69 and 3, that in Kafur Dheri Unit, waterlogged area is about respectively, with an overall average EC of 0.96 dS 43%. Water table was deep where natural drains were m-1. Results were found to be in the range of 0-4 dS passing nearby or where tube wells were working m-1, which indicates that salinity is not the major properly for a long time. Areas close to Warsak problem of the area, although at some locations white Gravity Canal (WGC) were not waterlogged and crust can be seen on soil surface. This was confirmed most of tube wells in the area were out of order. This by the farmers of the area that decline of water table could be because most part of the WGC is lined in results in the leaching of salts. Kafur Dheri Unit, which might have caused less seepage to groundwater. Similarly, water table was Minimum and maximum electrical conductivity deep in the surrounding areas of Warsak Dam. values of water samples were 0.36 and 1.28 dS m -1 at Mostly the surrounding areas of Kabul River Canal tube wells No. 2 and 12, respectively, with an overall (KRC) were waterlogged. This could be attributed to average EC of 0.56 dS m -1. Generally, all the values the unlined condition of the canal, which might have of samples were found to be in the range of 0 – 1.5 caused more seepage to ground water. Water logging dS m -1, which indicates tube well water is suitable for in the area has reduced the crop growth and may irrigation. This water can be used for irrigation cause salinity build up in the long run. without risk and need no safety precautions except normal drainage from root zone. The Kabul River Hydraulic Conductivity Canal (KRC) and Warsak Gravity Canal (WGC) Generally, hydraulic conductivity of the most exhibited lower EC values (i. e., 0.18 and 0.19 dS m - locations was in the range of 1.03 to 1.57 m/day 1, respectively). except for tube well No. 13 which gave the highest hydraulic conductivity value of 3.54 m/day, with an pH overall average of 1.53 m/day (Figure . 2). Soil Table VI shows that soil of Kafur Dheri Unit is texture is very important factor for hydraulic moderately alkaline in nature. Minimum and conductivity and results showed that area was maximum values of pH were 7.59 and 8.26 at tube

Syed Mohammad Bilal, et al. Effect of tube well drainage on water logging and salinity …… 52 wells No. 40 and PD3, respectively, with an overall average of 7.86. Results of water samples showed the CONCLUSION AND RECOMMENDATIONS similar trends of alkalinity. The pH of water samples Discharge of tube wells reduced from the design (6 to had minimum and maximum values of 7.45 and 8.83 53%). Water table was very shallow where tube wells at tube wells No. 33 and 59, respectively, with an were out of order and it was deep in those areas overall average of 8.17. The pH of both KRC and where tube wells were working or natural drains were WGC was identically 8.8 and were also found to be passing nearby. Hydraulic conductivity had normal in the similar range of tube well pH. The pH of both (1.03 to 3.54 m/day) values with respect to soil soil and water samples were found to be in the texture. Salinity is not the major problem of the area, normal range and have no harmful effects from crop although at some locations white crust can be seen on production point of view. The resultant range of pH soil surface. Soil and water of the area were slightly of both soil and water do not adversely affect the bio- alkaline which might be due to lower organic matter. availability of micro and macro nutrients; N, P, K, SAR of soil and water samples showed that soluble Zn, Cu, Mg etc. therefore there may be no need to Na+ compared to Ca ++ and Mg ++ was quite low treat water and soil. having no sodicity problem and water can be safely used for irrigation. On the basis of EC, pH and SAR, Sodium Adsorption Ratio (SAR) it can be concluded that soil and water of Kafur Dheri Table VII shows that minimum and maximum values Unit are normal. Soil does not require any remedy of SAR of soil samples were 0.10 and 1.02 at tube and water can be safely used for irrigation. Lower wells No. 69 and 3, respectively, with an overall actual discharges may be due to wear and tear of average of 0.34. Generally, results show that SAR is pumps and well screens and drought condition of the very low and there is no sodicity problem in the area. past few years. Routine maintenance and repair is necessary to keep tube wells in working condition. Table VIII shows that SAR of water samples ranged Re-boring and replacement of pump is required at from 0.13 to 0.91 with an overall average of 0.36. many locations where tube wells are out of order. General trends showed that water samples had very Surface drains should be remodeled and maintenance low SAR. The average SAR values at all locations should be carried out regularly for drainage of water were below 10 which meant that soluble Na contents from waterlogged areas. in the water and soil was low and water was usable for irrigation.

Tubewell No. 6 12 13 16 17 18 21 23 68 69 PD3 0

0.1 0.14 0.14 0.2 0.23 0.26 0.3 0.29 0.29 0.33 0.4

0.5

0.6 0.57 Watertable Depth (m) Watertable

0.7 0.69 0.71

0.8

0.85 0.9

Fig. 1: Average water table depth at different locations in Kafur Dheri Unit.

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4 3.54 3.5

3

2.5

2 1.57 1.44 1.31 1.5 1.09 1.14 1.14 1.03 1

0.5 Hydraulic Conductivity (m/day) Conductivity Hydraulic 0 6 13 16 17 18 21 23 PD3 Tubewell No.

Fig. 2: Hydraulic conductivity of selected locations in Kafur Dheri Unit, Peshawar

Table I Range of K values in relation to soil texture Soil Texture K (m/day) Gravelly coarse sand 10 – 50 Medium Sand 1 – 5 Sandy loam, fine sand 1 – 3 Loam, clay loam, clay (well structured) 0.5 – 2 Very fine sandy loam 0.2 – 0.5 Clay loam, clay (poorly structured) 0.002 – 0.2 Dense clay (no cracks, pores) < 0.002 Source: Ritzema (1994)

Table II Classification of salt affected soils based on analysis of saturation extracts Salinity Class ECe (dS m -1) SAR Non Saline <4 <13 Saline >4 <13 Saline-Sodic >4 >13 Non Saline-Sodic <4 >13

Table III Permissible limits of EC and SAR for irrigation water Parameters Usable Marginal Hazardous EC (dS m -1) 0 – 1.5 1.5 – 2.7 > 2.7 SAR 0 – 10 10 – 18 > 18

Syed Mohammad Bilal, et al. Effect of tube well drainage on water logging and salinity …… 54

Table IV Comparison of actual vs. design discharge of tube wells in Kafur Dheri Unit, Peshawar Tube well No. Design Q Actual Q Decrease (%) (liters/second) 2 71.0 34.9 51 4 42.6 30.9 27 6 71.0 34.9 51 9 28.4 17.8 37 12 58.2 54.0 06 15 42.6 27.2 36 19 45.4 30.4 33 25 85.2 54.5 36 33 14.2 7.59 44 36 39.1 32.3 17 47 42.6 25.2 41 49 21.3 9.94 53 50 42.6 24.7 42 53 63.9 50.5 21 59 42.6 27.0 37 63 63.9 36.4 43 66 63.9 51.4 20 69 42.6 32.3 24 Avg. 48.8 32.37 34 Std. Dev. 18.44 13.67 12.9 Coef. of Var. (%) 37.78 42.23 37.94

Table V Electrical conductivity of soil and water samples of selected locations in Kafur Dheri Unit, Peshawar Soil Samples Water Samples Tube well No. EC(dS m -1) Tube well No. EC(dS m -1) 2 0.75 2 0.36 3 2.80 4 0.77 10 1.30 6 0.74 14 1.00 9 0.64 16 0.90 12 1.28 17 0.70 15 0.66 18 0.98 16 0.60 19 0.70 19 0.56 22 0.75 25 0.45 25 1.65 33 0.88 33 0.70 36 0.62 36 0.65 47 0.44 40 0.70 49 0.44 48 0.64 50 0.42 49 0.70 51 0.40 51 0.40 52 0.38 53 0.70 53 0.38 56 1.30 55 0.47 63 1.05 59 0.39 64 1.15 60 0.55 68 0.58 63 0.43 69 0.30 66 0.41 71 1.20 71 0.37 PD3 1.05 DW1 0.59 RD 1.30 RD 0.71 Avg. 0.96 0.56 Std. Dev. 0.50 0.21 Coef. Var. (%) 52.08 37.50

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Table VI pH of soil and water samples of selected locations at Kafur Dheri Unit, Peshawar Soil Samples Water Samples Tube well No. pH Tube well No. pH 2 7.81 2 8.21 3 7.86 4 7.96 10 7.81 6 8.06 14 7.98 9 7.87 16 8.21 12 8.29 17 7.74 15 8.34 18 7.77 16 8.04 19 8.05 19 7.60 22 8.06 25 8.42 25 7.90 33 7.45 33 7.85 36 8.31 36 7.65 47 8.07 40 7.59 49 8.26 48 7.78 50 8.23 49 7.86 51 8.22 51 7.79 52 8.34 53 7.61 53 8.17 56 7.64 55 8.42 63 7.92 59 8.83 64 7.93 60 7.70 68 7.97 63 8.17 69 7.69 66 8.49 71 8.04 71 8.59 PD3 8.26 DW1 7.84 RD 7.73 RD 8.39 Avg. 7.86 8.17 Std. Dev. 0.18 0.31 Coef. Var. (%) 2.29 3.79

Syed Mohammad Bilal, et al. Effect of tube well drainage on water logging and salinity …… 56

Table VII Sodium adsorption ratio of soil samples of selected locations in Kafur Dheri Unit, Peshawar Tube well No. Na Mg Ca SAR (meq/l) 2 1.68 9.24 39.80 0.24 3 6.79 8.69 35.84 1.02 10 3.26 8.19 32.40 0.51 14 2.21 8.71 34.22 0.34 16 3.72 9.13 31.90 0.58 17 0.98 8.88 35.14 0.15 18 1.11 7.64 27.77 0.19 19 1.91 9.44 46.76 0.26 22 0.88 9.16 39.11 0.13 25 4.16 9.00 35.98 0.62 33 2.08 9.13 42.24 0.29 36 1.22 8.25 34.21 0.19 40 1.12 8.17 31.04 0.18 48 1.38 8.09 36.34 0.21 49 1.84 8.57 36.48 0.27 51 0.86 8.04 38.46 0.13 53 1.38 8.98 33.59 0.21 56 3.03 9.05 32.24 0.47 63 3.00 7.84 33.70 0.47 64 1.65 8.69 35.74 0.25 68 1.03 9.41 37.22 0.15 69 0.70 8.16 36.98 0.10 71 2.49 9.05 34.32 0.38 PD3 3.98 9.03 31.49 0.63 RD 4.28 9.17 42.36 0.60 Avg. 2.27 8.71 35.81 0.34 Std. Dev. 1.46 0.52 4.10 0.22 Coef. Var. (%) 64.32 5.97 11.45 64.71

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Table VIII Sodium adsorption ratio of water samples from selected tube wells in Kafur Dheri Unit, Peshawar Tube well No. Na Mg Ca SAR (meq/l) 2 0.55 9.07 10.00 0.13 4 1.42 9.59 9.74 0.32 6 1.63 9.71 8.76 0.38 9 1.13 8.26 9.19 0.27 12 1.02 8.21 9.80 0.24 15 2.49 8.17 9.00 0.60 16 1.90 9.35 9.05 0.43 19 1.35 8.01 9.69 0.32 25 1.26 8.78 10.00 0.29 33 2.37 9.38 8.23 0.56 36 2.37 9.30 10.25 0.54 47 1.07 8.42 8.26 0.26 49 1.39 8.47 8.70 0.34 50 1.55 9.85 9.97 0.35 51 1.18 8.00 9.36 0.28 52 0.95 9.85 9.34 0.22 53 0.98 9.04 10.00 0.22 55 1.43 9.56 9.61 0.33 59 3.64 7.93 8.10 0.91 60 1.16 9.71 9.35 0.27 63 1.24 9.47 9.09 0.29 66 1.08 9.69 9.50 0.25 71 1.05 7.85 8.35 0.26 DW1 1.39 9.21 8.90 0.33 RD 3.36 7.66 8.25 0.84 Avg. 1.98 8.92 9.23 0.36 Std. Dev. 2.46 0.71 0.63 0.57 Coef. Var. (%) 124.24 7.96 6.83 158.33 All the parameters (salinity, sodicity, and sodium adsorption ratio) were within the permissible range hence it can be safely used for irrigation.

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