Several studies carried out in long furrows have shown that surge flow irrigation offers the potential of increasing the efficiency of irrigation. The effects of surge flow in short fields, such as in Egypt, are still not well known, however. To investigate the effect of surge flow irrigation in short fields a series of experiments have been carried out at two different locations in Egypt. The first location with a clay soil was situated at the Agriculture Experimental Station, Assiut University, Assiut. The second location with a sandy soil was situated at the Assiut University Experimental Station for Desert Land, El-Wadi El-Assuity, Assiut. The blocked end furrow lengths and widths were 70 and 0.70m respectively. Three discharges were selected for each soil type, namely 0.46, 0.74 and 0.90 l s
1 for clay soil and 0.73, 1.0 and 1.4 l s
1 for sandy soil. For each discharge two cycle times were investigated, namely 16 and 24 minutes. For each cycle time three cycle ratios were chosen, 1/4, 1/2 and 3/4 for the 16-minute and 1/3, 1/2, and 2/3 for the 24-minute cycle time. The water content was measured at three locations, namely at the beginning, middle and end of the furrow. In each location three points were measured in a vertical line at a depth of 0–0.1, 0.1–0.3 and 0.3–0.7 m. The results show that surge flow irrigation leads to a more uniform water distribution along the furrows than continuous flow. This uniformity is more pronounced in clay soil than in sandy soil. Surge flow irrigation decreases the advance time in comparison to continuous flow. The reduction in advance time was more pronounced with the discharges of 0.74 and 1.0 l s
1 in clay and sandy soil respectively. The 24-minute cycle time is better than the 16- minute cycle time. The reduction in advance time with a cycle time of 24 minutes is due to the effect of the offtime. Different cycle ratios can be used but the 1/3 cycle ratio may be the best. In conclusion, surge flow irrigation under the short field conditions as prevailing in Egypt decreases the advance time, increases uniformity and efficiency by decreasing deep percolation and reduces applied water volume by 15–35%. Copyright #2004 John Wiley & Sons, Ltd.

Egypt is a country of tremendous land resources but limited water resources. The area of cultivated land is hardly exceeding 31,500 km2 or only 3.15% of the gross area. The river Nile is the main source of water in Egypt. The share of Egypt in the flow of the river Nile is at least 55.5 billion m3/year. Due to the huge increase in population growth the per capita share of productive land has fallen from 0.28 ha in 1898 to 0.05 ha in 1999. Not only the per capita share of land is going down; the per capita share of water is also falling sharply. This share of 850 m3 per capita per year is already below the so-called “water-poverty” line of about 1,000 m3 per capita per year. It will be even further reduced to an expected amount of 555 m3 per capita per year by 2025. In the recent years the Government established large scale agricultural projects in order to compensate the population growth. Expansion of irrigated agriculture has to be predominantly realized by increasing the water use efficiency. In Egypt, the dominant irrigation method is surface irrigation, which covers approximately 83% of the irrigated areas. The rest lies under sprinkler (12.5%) and drip (4.5%). Surface irrigation or gravity methods are generally characterized by a low application efficiency. One opportunity to increase the efficiency of surface irrigation is to convert it to sprinkler or drip. Converting surface irrigation systems to sprinkler or drip is highly expensive for a country like Egypt. Another option to increase the efficiency of surface irrigation systems is to convert the traditional irrigation method to surge flow irrigation. Surge flow irrigation is the intermittent application of water to furrows or borders in a series of relatively short on and off time periods. Varlev (1971) introduced the concept of surge flow irrigation in Bulgaria as a method for improving the uniformity of moisture distribution along the furrow. Stringham and Keller (1979) have essentially developed this irrigation method at Utah State University. Since then, it is widely applied in large areas in many countries like several states of the USA, Australia and Portugal. Large sizes and long furrows characterize the farms of these areas. The length of the furrows ranges from 300 m to 1700 m, especially the very long furrows are used in the USA. The main objective of the introduction of surge flow irrigation is to increase the efficiency and the productive use of water. Researches indicate that surge flow irrigation helps to increase application efficiency, increases crop production and saves water. Information about the proper stream size, initial on-time and cut–back phase became known. Moreover, guidelines for using surge flow irrigation in long fields have been established. Application of surge flow irrigation under small farm sizes and short field conditions is still not known. This study has been carried out to demonstrate the applicability of surge flow irrigation under short field conditions as they prevail in Egypt. To study the effect of surge flow irrigation two sets of field experiments have been established at two different locations. The first set of the experiments has been carried out in the Tunnel experimental plot of the Irrigation and Water Engineering Group, Wageningen University, the Netherlands. The aim of the experiments was to get familiar with surge flow irrigation and to operate it manually as well as to select the treatments, which can be applied under Egyptian conditions. The Tunnel contained two soil types namely, sandy clay and sandy clay loam. The second set of the field experiments has been carried out in two different locations in Assiut, Egypt. The first location is classified as clay soil and was situated at the Agriculture Experimental Station, Assiut University. The second location is classified as sandy soil. It was situated at the Assiut University Experimental Station for desert lands, El-Wadi El-Assuity, Assiut. It was a new place under reclamation and it was the first time for water to touch this land. The aim of the experiments in Egypt was to apply surge flow irrigation under the prevailing Egyptian conditions which are short fields and arid conditions, to select the best treatments which can be used for such conditions and to optimize water use as well as to establish guidelines for using surge flow irrigation efficiently under short field conditions. The lay-out of the field experiments was the same in the Netherlands and Egypt except for the slope, furrow width and a slight difference in some discharges. Under the Netherlands conditions the slope was 0.0058 m/m and furrow width 0.75 m for both soil types. The discharges were 0.46, 0.76 and 0.92 l/s for sandy clay soil meanwhile they were 0.76, 0.92 and 1.29 l/s for sandy clay loam soil. Under the Egyptian conditions the furrow width was 0.70 m for both soil types. The slope of clay soil was 0.0024 m/m and the discharges were 0.46, 0.74 and 0.90 l/s. Meanwhile, the slope of sandy soil was 0.004 m/m and the discharges were 0.73, 1.0 and 1.4 l/s. The furrow length in the experiments was 70 m for all soil types in the Netherlands and Egypt. The furrows had a blocked end. To monitor the advance and recession time, five points were established along the furrows, namely at 0 L, 1/4 L, 1/2 L, 3/4 L, and 1 L. The distance between two consecutive points was 17. 5 m. To study the effect of surge flow irrigation on the water distribution along the furrow, the soil moisture content was measured at three locations, namely at the beginning, middle and end of the furrows. In each location three points in a vertical were measured at a depth from 0.0 – 0.2 m, 0.2 – 0.4 m and 0.4 – 0.6 m below surface under the Netherlands conditions. Meanwhile, they were 0 - 0.1 m, 0.1 - 0.3 m and 0.3 - 0.7 m under Egyptian conditions. To investigate the water content distribution in the cross-sections, one furrow for each soil type was selected for the measurement of the water content at three different verticals in that cross-section, namely at the furrow bottom, at the middle of the side slope and on the outside ridge. The water content in the soil was measured by different methods according to the availability of the equipment in each location. The Time Domain Reflection (TDR) was used in both soil types under the Netherlands conditions. The profile probe method has been used in clay soil and the gravimetric method in sandy soil under the Egyptian conditions. The gravimetric method which was used in the sandy soil was due to the gravel, which hampered the installation of the fiberglass tubes. The cycle times and ratios were the same for all soil types under the Netherlands and Egyptian conditions. Two cycle times have been investigated, namely 16 and 24 minutes. Three cycle ratios were tested under each cycle time, 1/4, 1/2, and 3/4 for the cycle time of 16 minutes and 1/3, 1/2 and 2/3 for the cycle time of 24 minutes. The different cycle ratios were applied to study the effects of off-time on the water distribution along the furrow. Based on the discharges, cycle time and cycle ratio large numbers of alternatives of surge flow irrigation have been investigated beside the continuous flow for each soil type. The alternatives for surge flow irrigation during this investigation were related to the objectives of this research and have been chosen on basis of water management guidelines as presented in the literature. Some selected alternatives for a number of discharges have been repeated during the second and third irrigation to study the effect of surge flow irrigation during subsequent irrigations under the Netherlands conditions. The obtained results can be summarized as follows: - The research shows that surge flow irrigation offers the potential of increasing the distribution uniformity, thereby increases the effective use of water in surface irrigation systems. The benefits ascribed to surge flow irrigation result from a reduction in the infiltration rates; - Infiltration characteristics of the soil are major factors in the design of field irrigation systems. Reduced infiltration can lead to a faster water advance, thus leading to a reduction of deep percolation. The irrigation time is shortened and the water volume required for completion of the irrigation is reduced, which will improve the irrigation uniformity; - Surge flow irrigation is applicable in different soil types under short field conditions. It can save a large amount of water ranging from 15% to 35% during the first irrigation and from 12% to 15% overall the growing season based on the soil type, crop and the best combination of discharge, cycle time and cycle ratio; - The recommended discharges which maximize the water saving and which can be used under short field conditions are different for each soil type. Based on the obtained results the discharges of 0.46, 0.76, 0.74 and 1.0 l/s were the recommended discharges for sandy clay, sandy clay loam, clay and sandy soils respectively; - Comparison of the results of cycle times (16 and 24 minutes) indicated that both of them can be used but a 24 minutes cycle time is better than 16 minutes especially under the Egyptian conditions because it was dominant in both soil types, clay and sandy soils; - The cycle ratio which advances the water to the lower end of the furrow as fast as possible is different due to the soil type and the discharges. The cycle ratio of 1/3 may be recommended because it is the best case for half of all discharges used under the Netherlands and Egyptian conditions. Operating surge flow irrigation with high sophisticated surge valve leads to any possible cycle ratio meanwhile operating it manually leads only to one option, which is 1/2 cycle ratio; - A proper slope configuration is required for getting a good moisture distribution along the furrow although it has a little effect on surge flow irrigation. In general, gentle slopes are required for fine textured soils, moderate slopes can be used in medium textured soils and steep slopes are recommended for coarse textured soils; - The best time for using surge flow irrigation with its maximum benefits is at the first irrigation at the beginning of the season. It can also be used during subsequent irrigation but with less effect compared to the first irrigation in coarse textured and tilled soils; - Comparison of the predicted water advances by SIRMOD III in all the experiments with measured water advances indicated that with a good representation of the infiltration parameters, surge flow irrigation under short field conditions can be successfully simulated, designed and evaluated. Management alternatives of discharges and cycle times can be obtained by using SIRMOD III model; - Surge flow irrigation can be considered environmental friendly. It tends to decrease the infiltration rate and consequently decreases the deep percolation. As the deep percolation is decreased all fertilizers and pesticides moving downward will be decreased; kept in the upper part of the soil; available for the plant use and far away form the groundwater table; thus the groundwater will be protected against the main source of agricultural pollution; - Model results show that the same amount of yields can be produced under surge flow irrigation with less supply compared to continuous flow, or higher crop yields can be produced under surge flow irrigation compared to continuous flow when the same gross irrigation supply is used. - Surge flow irrigation is an effective irrigation method to save water and/or to increase crop production in short field conditions like those that prevail in Egypt.

Surge flow irrigation is a technique in furrow irrigation that can contribute to improve application efficiencies and distribution uniformity with diminished water and sediment losses. Literature reviews show that surge flow irrigation may decrease water use and increase crop production. Several studies which were carried-out in long furrows have shown that surge flow irrigation offers the potentiality of increasing the efficiency of irrigation, however the effects of surge flow in short furrows are still not well known. To investigate the effect of surge flow irrigation in short furrows a series of experiments have been carried-out on four soil types at two countries, Egypt and The Netherlands. The first location in Egypt was on clay soil at the Agriculture Experimental Station, Assiut University, Assiut. The second location was on sandy soil at Assiut University Experimental Station for Desert Land, El-Wadi El-Assuity, Assiut. The experiments under the Netherlands conditions were carried out at the Tunnel experimental setting of the Irrigation and Water Engineering Group, Wageningen University. Two soil types were classified inside the tunnel, sandy clay and sandy clay loam soils. The blocked end furrow lengths and widths were 70 and 0.70 m respectively. One discharge was selected for each soil type, namely 0.74 l/s for clay soil, 1.0 l/s for sandy soil and 0.76 l/s for sandy clay and sandy clay loam soil. For each discharge two cycle times were investigated, namely 16 and 24 minute. For each cycle time three cycle ratios were chosen, 1/4, 1/2 and 3/4 for 16 minute and 1/3, 1/2, and 2/3 for 24 minute cycle time. The water content was measured at three locations, namely at the beginning, middle and end of the furrow. In each location three points were measured in a vertical line at a depth from 0 - 0.1, 0.1 - 0.3 and 0.3 -0.7 m. Crop yields was simulated in relation to water supply for clay and sandy soils using the cropwat model The results showed that surge flow irrigation lead to more uniform water distribution along the furrows than continuous flow. Also, surge flow irrigation decreased the advance time in comparison to continuous flow. The reduction in advance time was more pronounced in clay, sandy clay and sandy clay loam soil than sandy soil. The 24 minutes cycle time was better than the 16 minutes cycle time. The reduction in advance time with cycle time of 24 minutes is due to the effect of the off-time. Different cycle ratios may be used however the 1/3 cycle ratio was the best. The simulation results of cropwat model indicated that using optimal surge flow irrigation to simulate crop yield was better than using optimal continuous flow. Using optimal surge flow irrigation in the simulation revealed distinct differences in yield reduction between continuous and surge flow irrigation compared to the results based on optimal continuous. In conclusion surge flow irrigation under short furrows decreased the advance time, increased uniformity and efficiency by decreasing deep percolation and it reduceing applied water volume 15% to 35 %. Surge flow irrigation is an efficient tool to produce higher yields than continuous flow by using the same gross irrigation supply

Surge flow irrigation is a surface irrigation method that can be used to improve the efficiency of water applied by furrows. Several studies have shown that surge flow irrigation offers the potential of increasing the distribution uniformity, thereby increasing the efficiency of surface irrigation. Most of these studies were conducted in fields with long furrows, but the effects of surge flow in short fields, like in Egypt, are still not well known. In order to investigate the effect of surge flow irrigation in short fields a series of experiments have been carried-out in two different locations in Egypt. The first location with a clay soil was situated at the Agriculture Experimental Station, Assiut University, Assiut. The second location with a sandy soil was situated at the Assiut University Experimental Station for Desert Land, El-Wadi El-Assuity, Assiut. The furrow length was 70 m and the furrow width was 0.70 m for both locations. The furrows had a blocked end. Three discharges were selected for each soil type, namely 0.46, 0.74 and 0.90 l/s for clay soil and 0.73, 1.0 and 1.4 l/s for sandy soil. The water was conveyed via siphons to the furrows. For each discharge two cycle times were investigated, namely 16 and 24 minute. For each cycle time three cycle ratios were chosen, i.e. 1/4, 1/2 and 3/4 for 16 minute and 1/3, 1/2, and 2/3 for 24 minute cycle time. The different cycle ratios were applied to study the effects of off-time on the water distribution along the furrow. The water content was recorded by a Profile-probe at three locations, namely at the beginning, middle and end of the furrow. In each location three points were measured in a vertical at a depth from 0 - 0.1, 0.1 - 0.3 and 0.3 - 0.7 m-surface. The results show that surge flow irrigation leads to a decrease in advance time compared to continuous flow. The reduction in advance time is more pronounced for high than for low discharges and also more in coarse than in fine textured soils. For both cycle times the advance time reduces compared to continuous flow in both soil types, except for 0.46 l/s in clay soils; this discharge leads to an increased advance time. For the other cases the reduction was more pronounced for a cycle time of 24 minute than for 16 minute. This reduction was due to the effect of off-time. When the off-time is long enough to infiltrate all the water before the second surge starts, the mechanism of surge flow works effective. The water content along the furrow is also more uniformly distributed than for continuous flow. In conclusion surge flow irrigation under the prevailing conditions in Egypt decreases the advance time, increases the efficiency and uniformity, and hence, it saves water.

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Egypt is situated in the North East of Africa and includes parts of Asia (Sinai Peninsula). Egypt is a country of tremendous land resources but limited water resources. The gross area of Egypt is about one million km2 while the area of cultivated land is hardly exceeding 31,500 km2 or only 3.15% of the gross area. The population is concentrated on almost 5% of the gross area only, in the narrow strip, which borders the river Nile in the upper and middle part of the country and in the Nile Delta in the lower part. The population of Egypt increased dramatically from 8 million in 1898 to about 65 million at present. It is expected that the population will reach 100 million by the year 2025. Due to this huge increase the per capita share of land fell from 0.28 ha in 1898 to 0.05 ha in 1999. Not only the per capita share of land is going down; the per capita share of water is also falling sharply. Now, this share is already below the so-called “water-poverty” line of about 1,000 m3 per capita per year. The annual availability of water per capita is at present 850 m3. It will be even further reduced to an expected amount of 555 m3 by 2025. Expansion of irrigated agriculture has to be predominantly realized by increasing the water use efficiency. In Egypt, the dominant irrigation method is surface irrigation. It covers approximately 85% of the irrigated areas. The rest lies under modern irrigation systems (sprinkler 12.5 % and drip 2.5 %). Surface irrigation methods (gravity methods) are generally characterized by low efficiency. One opportunity to increase productivity of Nile water is to capture more of the drainage outflow and to convert it into a productive use. However, initial estimates based on downstream environmental outflow requirements show only 4 to 5 billion m3 can be captured with conservation efforts. Only well conceived projects to increase efficiency on a local level may achieve slight increases in the depleted fraction when these reduce drainage discharge to the sea. Surge flow is a practical tool to conserve that water. It is a technique in furrow irrigation that can contribute to improved application efficiencies and distribution uniformity with diminished water and sediment losses. This MSc thesis presents a research proposal to select some ways for water saving under Egyptian conditions. Literature reviews show that surge flow irrigation may save water and increase crop production and therefor it might be a promising method in Egypt. However, there are many limitations in surge flow irrigation that need more investigation, especially in short fields. These limitations are: - its application is limited to land, which is suitable for surface irrigation; - the variability of surge flow effects on compacted and uncompacted furrows may still exist in a reduced form. Moreover, the relationships between stream size and length of furrow and cycle time need more investigations; - more information is needed to establish the best management practices, including the optimum combination of inflow rates, cycle times, and number of surges; - appropriate slope configurations to minimize runoff and deep percolation. Surge flow irrigation method might be recommended for Egypt for several reasons, which are - the application of surge flow irrigation is limited to land, which is suitable for surface irrigation. This means that 85% of the cultivated area in Egypt is potentially suitable for surge flow irrigation; - surge flow irrigation can be used in furrows or in borders, so it is suitable for the most important crops in Egypt, as these crops are cultivated in furrows except wheat, which is cultivated in borders or basins; - the expenses are less than for sprinkler or drip irrigation. Meanwhile, its net return is the highest in comparison to six other irrigation systems, namely medium pressure center-pivot (MPCP), low pressure center-pivot (LPCP), low, drift nozzle center-pivot (LDN), low energy precision application center-pivot (LEPA), furrow flood (FF), surge flow (SF), and subsurface drip (SD); - surge flow is an effective method to get higher crop yield production; - surge flow saves water in an effective way. From this study follows that, this topic should be extensively investigated in a Ph.D. Research. The main objectives of the research, will be to formulate those measures, which improve surface irrigation methods on farm scale, increase water saving and increase field crop production by applying surge flow irrigation under conditions that prevail in Egypt.

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