The impact of climate on the variation in the quantitative characteristics of the Diyala River water in Diyala and Baghdad Governorates

Abstract

By relying on data from the two stations (Darbandi Khan Dam Head and Hamrin Dam Head) for water revenue and data from the two stations (Darbandi Khan Dam Tail Discharge and Hamrin Dam Tail Discharge), the quantitative characteristics of water and the water discharge were studied during the study period. The study showed that the quantitative characteristics of the Diyala River water vary between stations and during seasons, according to the variation in rainfall amounts. The Darbandi Khan Dam discharge station recorded the highest annual water discharge rate during the wet water year (1992-1993), reaching (260.2 m3/s), with a discharge coefficient (K) value of (2.4), while it recorded the lowest annual water discharge rate during the dry water year (2020-2021), reaching (30.1 m3/s), with a discharge model coefficient (K) value of (0.3). While the Hamrin Dam discharge station recorded the highest annual water discharge rate during the wet water year (2018-2019) amounting to (346.5 m3/s), with a discharge model coefficient (K) value of (3.2), and the lowest water discharge rate was recorded during the dry water year (2008-2009) amounting to (26.1 m3/s), with a discharge model coefficient (K) value of (0.2). As for the seasonal water discharge rates, they varied between the seasons of the study year, and the Dar Bandi Khan Dam discharge station recorded the highest seasonal water discharge rate during the spring season amounting to (183.8 m3/s), while it recorded the lowest seasonal water discharge rate during the autumn season amounting to (88.1 m3/s), and the Hamrin Dam discharge station recorded the highest seasonal water discharge rate during the summer season amounting to (122.9 m3/s), and recorded the lowest seasonal water discharge rate during the winter season amounting to (85.2 m3/s). The discharge stations (Dar Bandi Khan Dam and Hamrin Dam) recorded the highest monthly water discharge rate during the month of April, reaching (152.6, 128.2) m3/s, respectively, while the discharge station (Dar Bandi Khan Dam) recorded the lowest monthly rate during the month of September, reaching (86.0 m3/s), while the discharge station (Hamrin Dam) recorded the lowest monthly rate during the month of January, reaching (77.9 m3/s).