Effects of Continuous Flushing on the Sediment Removal Efficiency in Settling Basins of Small Scale Irrigation Projects; A Case Study of Kiriku-Kiende Irrigation Project, Embu County, Kenya

Abstract

Effects of continuous flushing on the sediment removal efficiency in settling basins of small scale irrigation projects; a case study of kiriku-kiende irrigation project, embu county, kenya Submit Manuscript | http://medcraveonline.com IntroductionSurface irrigation is a widely used farming system for crop production as it requires less skilled labour and involves less operational cost. Surface irrigation systems contributed to about 90% of the world's crop land irrigation promoting furrow irrigation as the main application method.1 However, poor design and management, non-uniformity of water application, and over-irrigation featured in surface irrigation are responsible for inefficient irrigation, leading to wastage of water, water logging, salinization, and pollution of surface and ground water resources.2 Irrigated agriculture is under serious risk due to substantial soil losses from highly erodible soils.3−5 Irrigated agriculture has been faced with challenges such as sediment loading in the river basins, settling tanks and dams.6 Many factors such as surface and solids loading rates, tank type, solids removal mechanism, inlet design, weir placement and loading rate affect the capacity and performance of a settling tank. 7 The management of sediments in river basins and waterways has been an important issue for water managers throughout the history as from the ancient Egyptians managing sediment on floodplains.8 Currently, water managers are faced with similar challenges mainly resulting in siltation of water reservoirs, reduced capacity of water transport, annual irrigation acreage reduction and high maintenance cost for an irrigation project. 9,10Kenya is not exempted from the dangers posed by sedimentation and siltation in her water bodies. According to, 11 a high proportion of sediments generated in the catchment areas is delivered through soil erosion to the rivers and lakes. Effective management of sediments from rivers during irrigation water abstraction by use of settling basins has become increasingly important from an economic and environmental perspective. Many factors such as surface and solids loading rates, tank type, solids removal mechanism, inlet design, weir placement and loading rate affect the capacity and performance of a settling tank.7 Sediments in irrigation network causes clogging and blocking of irrigation structures. This contributes to overall low irrigation water delivery to the farms. This study was to examine the effect of continuous sediment flushing versus desilting. This would form a basis for designers of settling basin for consideration of continuous flushing for eventual increase of the overall efficiency of irrigation systems. In Kenya, smallholder irrigation development is one of the key strategies for land use intensification with expected positive effects on rural incomes and poverty alleviation. About 20% (106,600 ha) of the potential irrigable land is already under irrigation where 50% (53,300) of this area is under smallholder irrigation. 12−14Table 1 presents the ...

Mapping the vulnerability of irrigation sand traps in a tropical volcanic basin, Indonesia

“…The susceptibility of this sand trap can be employed as a consideration in the decision support system (DSS) for prioritizing irrigation sand traps that are incorporated into a river basin for further performance-related research. For example 7 , evaluated the performance of the sand trap in the Wonji Shoa Sugar Estate Irrigation Scheme (Ethiopia) 81 , simulated the sand trap in the Sapon irrigation network (Indonesia) 82 , studied how to improve the performance of the sand trap in large scale irrigation scheme (Thailand) 83 , modeled the efficiency of settling basin in small scale irrigation projects (Kenya) 9 , assessed sand traps in the Pendowo and Pijenan Irrigation Scheme (Indonesia), while 8 modeled sand trap behavior in the Pengasih Irrigation Scheme (Indonesia). These studies conclude that a sand trap's performance can be measured by capacity to hydraulically accumulate and flush sediment throughout regular flushing operations and that this will allow the sand trap to keep working correctly due to sedimentation problems in the irrigation network.…”

Mapping the Vulnerability of Irrigation Sand Traps in a Tropical Volcanic Basin, Indonesia

“…The susceptibility of this sand trap can be employed as a consideration in the decision support system (DSS) for prioritizing irrigation sand traps that are incorporated into a river basin for further performance-related research. For example, (Paulos et al, 2006) evaluated the performance of the sand trap in the Wonji Shoa Sugar Estate Irrigation Scheme (Ethiopia), (Nindito et al, 2008) simulated the sand trap in the Sapon irrigation network (Indonesia), (Wongtragoon et al, 2016) studied how to improve the performance of the sand trap in large scale irrigation scheme (Thailand), (Namu et al, 2017) modeled the e ciency of settling basin in small scale irrigation projects (Kenya), (Widaryanto, 2018) assessed sand traps in the Pendowo and Pijenan Irrigation Scheme (Indonesia), while (Pradipta et al, 2022) modeled sand trap behavior in the Pengasih Irrigation Scheme (Indonesia). These studies conclude that a sand trap's performance can be measured by capacity to hydraulically accumulate and ush sediment throughout regular ushing operations and that this will allow the sand trap to keep working correctly due to sedimentation problems in the irrigation network.…”