Field Measurement of Accumulated Surface Water and Infiltration Depth in a Flood-Prone Langol Catchment of Manipur Valley Region

Abstract

AbstractThe cause of flooding in the Manipur valley (where the study area is located in the North Eastern region of India) is mainly due to poor urban drainage, deforestation, vanishing traditional recharge structures, heavy runoff, and less infiltration in the degraded watershed in the upper reach of the river during the rainy season. The aim and objectives of this study are to determine the accumulated inundated water in the Langol catchment area and to get information on predicted floods to facilitate early preparation and planning before flood events. Then infiltration depth is also measured to understand the water holding capacity in the region where the study area is majorly covered by clay and clay loam soil, which has less infiltration capacity. The measurements were taken at different site locations (15 locations for surface water depth and 03 locations for infiltration depth) on a weekly basis (August to September, 2021 for surface water depth and February to September, 2022 for infiltration depth). The maximum accumulated water depth measured was 45 cm, and the minimum was 0.3 cm in the catchment area during the measurement time. In February 2022, maximum infiltration depth was observed at 0.39 cm, with an average of 0.2 cm. From the results, it was concluded that soil in the NIT campus has less infiltration capacity and, therefore, the only means for preventing the frequent inundation of surface water is through the provision of a proper drainage system considering the low-lying landscape of the catchment area.KeywordsAccumulated water depthFlood-prone zoneInfiltration depthLangol catchmentManipur valley