Your search found 28 records
(Location: IWMI-HQ Call no: 631.7.1 G232 LIT Record No: H0157)
(1.27 MB)
High water table levels presenting hazards to crop growth were measured at field sites in upper, middle, and lower Egypt. Water table contribution to evapotranspiration was significant at each site. A water balance model of the water table aquifer was used to predict the effect of various interventions on water table levels. Desirable lower water table levels could not be maintained through on-farm irrigation efficiency improvement including lining of on-farm channels while using surface irrigation methods. Branch, distributary, and private canal lining would have negligible effect on water table levels. Corresponding increases in required water deliveries would be expected.
(Location: IWMI-HQ Call no: 631.7.7 G232 GWI Record No: H039)
(1.77 MB)
A water delivery system in Middle Egypt was renovated to providecontrolled gravity flow for more efficient distribution and use of irrigation water. After thorough planning and design, structural specifications were prepared for watercourse renovation, hydraulic control structures, internal access roads, and land leveling. Contracts were awarded and construction was initiated. The effort to perform extensive renovation of a water delivery system at the farm level required an experimental approach to develop the best methods for quality construction with the least disruption to farming practices and irrigation schedules. A summary of the specifications, the contracts and costs, the construction procedures, and recommendations for future work were prepared.
(Location: IWMI-HQ Call no: 631.7.2 G232 WAR Record No: H0878)
Data were collected from three sites in Egypt's Nile Valley and Delta to determine saturated hydraulic conductivity in the clay-silt water table aquifer and vertical leakage to the underlying Nile River sands. Auger hole test results gave saturated horizontal hydraulic conductivities of 1103 mm/day for Abyuha in the Middle Nile Valley, 197 mm/day for Beni Magdul near Cairo, and 103 mm/day for Abu Raya in the northern Delta. Auger hole, permeameter, and consolidation tests resulted in saturated vertical hydraulic conductivities of 0.03 to 4.9 mm/day for Abyuha, 0.03 to 0.87 mm/day for Beni Magdul, and 0.03 to 0.45 mm/day for Abu Raya. Several methods were used to determine vertical leakage: Darcy's law, water table decline, water budget, pumping test, and analytical solution. Average vertical leakage rates were very low for each site: 0.59 mm/day in Abyuha, 0.64 mm/day in Beni Magdul and 0.47 mm/day in Abu Raya. These results indicate poor natural drainage characteristics in the clay-silt layer which contribute to the high water table conditions observed throughout Egypt.
4 Somasekra, B. M. S.; Mohammed, R. A.; Imbulana, K. A. U. S.; Gates, T, K.; Bandaranayake, M. A. W.; Nelson, L. J.; Somasundera, J. W. D.; Shaner, W. M.; Hettige, S.; Kilkelly, M. K. 1987. Diagnostic analysis of Minneriya Scheme, Sri Lanka: 1986 Yala - Discipline reports. Fort Collins, CO, USA: Colorado State University. xiv, 211p. (WMS report 59)
(Location: IWMI-HQ Call no: 631.7.8 G744 SOM Record No: H04024)
5 Gates, T. K.; Ley, T. W.; Clyma, W. 1981. Systems analysis for improvement of surface irrigation. Paper presented at the 1986 Summer Meeting, American Society of Agricultural Engineers, Orlando, 21-24 June 1981.
(Location: IWMI-HQ Call no: P 101 Record No: H04105)
(Location: IWMI-HQ Call no: PER Record No: H05592)
7 Gates, T. K.; Grismer, M. E. 1989. Irrigation and drainage strategies in salinity-affected regions. Journal of Irrigation and Drainage Engineering, 115(2):255-284.
(Location: IWMI-HQ Call no: PER Record No: H005823)
(1.57 MB)
8 Molden, D. J.; Gates, T. K.. 1990. Performance measures for evaluation of irrigation-water delivery systems. Journal of Irrigation and Drainage Engineering, 116(6):804-823.
(Location: IWMI-HQ Call no: PER Record No: H07367)
(Location: IWMI-HQ Call no: PER Record No: H08270)
(Location: IWMI-HQ Call no: PER Record No: H09487)
(Location: IWMI-HQ Call no: PER Record No: H09488)
(Location: IWMI-HQ Call no: PER Record No: H010391)
13 Bakry, M. F.; Gates, T. K.; Khattab, A. F. 1992. Field-measured hydraulic resistance characteristics in vegetation-infested canals. Journal of Irrigation and Drainage Engineering, 118(2):256-273.
(Location: IWMI-HQ Call no: P 2349 Record No: H011384)
(Location: IWMI-HQ Call no: PER Record No: H015998)
15 Gates, T. K.; Ahmed, S. I. 1995. Sensitivity of predicted irrigation-delivery performance to hydraulic and hydrologic uncertainty. Agricultural Water Management, 27(3/4):267-282.
(Location: IWMI-HQ Call no: PER Record No: H016777)
16 Garcia, L. A.; Gates, T. K.; Jensen, M. E.; Podmore, T. H. 1992. Management support system for conjunctive irrigation and drainage. In Drainage and water table control: Proceedings of the Sixth International Drainage Symposium, 13-15 December 1992, Nashville, Tennessee. St Joseph, MI, USA: ASAE. pp.12-19.
(Location: IWMI-HQ Call no: 631.62 G000 DRA Record No: H019147)
17 Moncada, E.; Fontane, D. G.; Gates, T. K.. 1994. Evaluating multi-purpose reservoir operations using fuzzy dynamic programming. In Fontane, D. G.; Tuvel, H. N. (Eds.), Water policy and management: Solving the problems: Proceedings of the 21st annual conference, ASCE, Denver, Colorado, May 23-26, 1994. New York, NY, USA: ASCE. pp.111-114.
(Location: IWMI-HQ Call no: 333.91 G000 FON Record No: H019795)
18 Fowler, M.; May, D. R.; El-Hakim, O.; Bennally, A.; Johnson, A.; Spaulding, S.; Begay, W.; Gates, T. K.. 1994. Development of a Geographical Information System for on farm management. In Fontane, D. G.; Tuvel, H. N. (Eds.), Water policy and management: Solving the problems: Proceedings of the 21st annual conference, ASCE, Denver, Colorado, May 23-26, 1994. New York, NY, USA: ASCE. pp.132-135.
(Location: IWMI-HQ Call no: 333.91 G000 FON Record No: H019798)
19 Azevedo, L. G.; Gates, T. K.; Fontane, D. G. 1994. Integration of water quantity and quality planning. In Fontane, D. G.; Tuvel, H. N. (Eds.), Water policy and management: Solving the problems: Proceedings of the 21st annual conference, ASCE, Denver, Colorado, May 23-26, 1994. New York, NY, USA: ASCE. pp.388-391.
(Location: IWMI-HQ Call no: 333.91 G000 FON Record No: H019827)
20 Gates, T. K.; Alshaikh, A. A.; Ahmed, S. I.; Molden, D. J. 1991. Irrigation delivery design with parameter and objective uncertainty. In Ritter, W. F. (Ed.), Irrigation and drainage: Proceedings of the 1991 National Conference sponsored by the Irrigation and Drainage Division of the American Society of Civil Engineers and the Hawaii Section, ASCE, Honolulu, Hawaii, July 22-26, 1991. New York, NY, USA: ASCE. pp.560-566.
(Location: IWMI-HQ Call no: 631.7 G430 RIT Record No: H019913)
This paper investigates the effects of uncertainty in the design of hydraulic structures in an open-channel system for irrigation water delivery. Uncertainty due to ambiguity in the values of physical parameters and due to vagueness in the specification of system performance objectives (adequacy, efficiency, dependability and equity) is modeled. Two design objectives, maximum performance and minimum cost, are considered in a simple illustrative example. Implications for design and analysis of large-scale delivery networks in an uncertain environment are discussed.
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