REVIEW ARTICLE VALIDATION AND UTILIZATION OF THE SOIL CONSERVATION SERVICES (SCS) FOR FURROW IRRIGATION DESIGN METHOD Samir M. Ismail, *Tarek K. Zin El-Abedin, Abd-Allah Zein El-Din and Abeer Hedia Department of Agriculture Engineering, Alexandria University, Egypt ARTICLE INFO ABSTRACT The main objective of this work is to validate and utilize USDA-SCS furrow irrigation design method. Soil data were collected from 22 locations in Nile Delta to get the soil texture and infiltration functions. According to the collected data, the Egyptian soils were classified into three groups: clay, clay loam, and sandy loam. Linear regression analysis was used to determine the average infiltration constants for each group. It was found that the infiltration constant C= 7 for all families must be adjusted in order to use the USDA-SCS intake families for Egyptian soils, the constant ’C’ in the infiltration equation is taken C =4 for clay soil, C =11 for clay loam soil, and C = 17 for sandy loam soil. The SCS method and volume balance equations were programmed in MATLAB computer language (EGY) to design and evaluate furrow irrigation. The program output was validated using field experiments data conducted at the Etay El-baroud ARC, Behera Governorate. According to results, SCS model and Volume Balance can be used for determining infiltration depths and advance times along furrow length for the three groups of the Egyptian soils. The field experiments and volume balance results are very close to each other. However, Experimental results are different from SCS model, but using a coefficient made close agreement. A sensitivity analysis was performed using the EGY model to study the effects of varying Manning coefficient, land slope, inflow rate cutoff time length of run, and soil type on the performance parameters. Copyright © 2014 Samir M. Ismail et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. INTRODUCTION Surface irrigation referred to as “flood irrigation”, the essential feature of this irrigation system is that water is applied at a specific location and allowed to flow freely over the field surface and thereby apply and distribute the necessary water to refill the crop root zone. Surface irrigation has evolved into an extensive array of configurations which can broadly be classified as: (1) basin irrigation, (2) border irrigation, (3) furrow irrigation, and (4) wild flooding. The distinction between the various classifications is often subjective. For example, a basin or border system may be furrowed. Wild flooding is a catch-all category for the situations where water is simply allowed to flow onto an area without any attempt to regulate the application or its uniformity. Primary goal of efficient surface irrigation is to complete the advance phase as quickly as possible without erosion. Because of the advance time, difference in opportunity times may exist between the upper and lower ends of the fields that may cause non- uniformity in the depth of water infiltrated along the furrow length. Increasing furrow inflow rate, reducing the length of *Corresponding author: Tarek K. Zein El-Abedin Department of Agriculture Engineering, Alexandria University, Egypt run and improving the slope of the field can reduce the differences in advance time and help improve the performance of an irrigation system. Many commercial systems have been found to be operating with significantly lower and highly variable efficiencies. Previous research in the sugar industry (Raine and Bakker, 1996) found application efficiencies for individual irrigation ranging from 14 to 90%. While well design and managed surface irrigation systems may have application efficiencies of up to 90% (Anthony, 1995). Furrow irrigation method principal of applying water at a specific rate of flow into spaced small channels, these channels convey the water down or across the slope of the field to infiltrates in the soil both vertically and horizontally (Hornbuckle, 1999). How long water must be applied in the furrows depends on the volume of water required to fill the soil to the desired application depth, according to the intake rate of the soil, and the spacing of the furrows (Walker, 1998). So water applied until the desired application depth and lateral penetration are obtained. Main objectives: Model the (SCS) soil conservation service furrow irrigation system, simulate performance indicators of the (SCS) system, categorize Egyptian soils characteristics and finally utilize ISSN: 0976-3376 Asian Journal of Science and Technology Vol. 5, Issue 12, pp.745-754, December, 2014 Available Online at http://www.journalajst.com ASIAN JOURNAL OF SCIENCE AND TECHNOLOGY Article History: Received 04 th September, 2014 Received in revised form 11 th October, 2014 Accepted 02 nd November, 2014 Published online 30 th December, 2014 Key words: USDA-SCS furrow irrigation design, Soil texture, Infiltration functions, USDA-SCS intake families, Egyptian soils, SCS model, Volume Balance, Manning coefficient, Land slope, Inflow rate and Soil type.