Mathematical Modeling-Based Management of a Sand Trap throughout Operational and Maintenance Periods (Case Study: Pengasih Irrigation Network, Indonesia)

Abstract

Surface irrigation networks in Indonesia are damaged by several factors, and sedimentation is among the most severe challenges. Sand traps play a substantial role in improving irrigation system efficiency by reducing sedimentation. There are two periods in sand trap operation: the operational and maintenance periods. Pengasih is one of the irrigation schemes implemented in the Progo Opak Serang (POS) River Basin, which has a high level of erosion. This study aimed to propose an appropriate management strategy for the Pengasih sand trap as the first barrier in irrigation network sedimentation based on mathematical modeling. The HEC-RAS simulation software was used to simulate the sand trap hydraulic behaviour. The results show that the validated Manning’s coefficient was 0.025. The optimal transport parameters were Laursen for the potential function, Exner 5 for the sorting method, and Rubey for the fall velocity method. The recommended flushing timeframe is 315 min, with a discharge of 2 m3/s. We suggest that the sand trap flushing frequency be performed twice a year, and it can be performed at the end of March and October. This coincides with the end of the first and third planting seasons of the irrigation scheme.

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.…”

“…Irrigation needs for rice plants still dominate the overall irrigation requirements in Indonesia, and it is delivered through a surface irrigation network (Vermilion et al, n.d.). The irrigation network is typically equipped with a sand trap-a device behind the irrigation intake-to deposit sediment carried from the river before it enters the primary irrigation channel (Paulos et al, 2006;Pradipta et al, 2022). Sand traps are commonly employed to enhance the e cacy of irrigation systems and have an important function for preventing or controlling canal sedimentation (Widaryanto, 2018).…”

“…The sediment deposited in the sand trap is cleaned on a frequent basis through manual or hydraulic techniques (Mustafa et al, 2013;Pradipta et al, 2020;Widaryanto, 2018). Sand trap is the initial barrier preventing sediment from the river before entering the irrigation network (Pradipta et al, 2020(Pradipta et al, , 2022Widaryanto, 2018). Therefore, insu cient sand trap performance might lead to sedimentation in the irrigation system.…”

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

“…Irrigation needs for rice plants still dominate the overall irrigation requirements in Indonesia, and it is delivered through a surface irrigation network 6 . The irrigation network is typically equipped with a sand trap-a device behind the irrigation intake-to deposit sediment carried from the river before it enters the primary irrigation channel 7 , 8 . Sand traps are commonly employed to enhance the efficacy of irrigation systems and have an important function for preventing or controlling canal sedimentation 9 .…”

“…The sediment deposited in the sand trap is cleaned on a frequent basis through manual or hydraulic techniques 9 , 10 , 12 . Sand trap is the initial barrier preventing sediment from the river before entering the irrigation network 8 – 10 . Therefore, insufficient sand trap performance might lead to sedimentation in the irrigation system.…”