Rating Curve Development and Validation on Tordzie Watershed
Mexoese Nyatuame,
Sampson Agodzo,
Leonard Amekudzi,
Bismark Mensah-Brako
Issue:
Volume 10, Issue 3, September 2022
Pages:
49-55
Received:
20 July 2022
Accepted:
4 August 2022
Published:
15 August 2022
DOI:
10.11648/j.hyd.20221003.11
Downloads:
Views:
Abstract: Basin discharge is a crucial hydrological parameter in water resources management. However, its direct measurement is a difficult task to a hydraulic engineer. The quality of the data was examined employing regression analysis to check correlation between the discharge (Q) and stage (H). The mean values of the two variables were then adopted to find the difference of value between zero gauge and level of zero flow, “H0”, and locality constants (“K” and “n”) to fit into rating curve equation and plotted the stage-discharge rating curve. The generated equations for the network stations were Q = 7.4716(H-0.1096)1.024 for Honuta, Q= 8.2105 (H-0.30)1.2415 for Kpetoe and for Tordzinu Q = 3.937 (H-0.48)1.3178. The formulated equations were validated with historical stage and discharge data. The correlation coefficients were 99.78%, 99.85% and 98.73% for Honuta, Kpetoe and Tordzinu respectively. The Correlation coefficients indicated percent of original uncertainty explained by the analysis. The standard deviations (and standard errors) were 1.81% (0.34%), 15.58% (4.50%) and 14.25% (4.11%) for Honuta, Kpetoe and Tordzinu, respectively, on Tordzie watershed. The calculated rating curve has several advantages. Among them, it is able to estimate accurate discharge during the flood based on extrapolation which is difficult to measure directly.
Abstract: Basin discharge is a crucial hydrological parameter in water resources management. However, its direct measurement is a difficult task to a hydraulic engineer. The quality of the data was examined employing regression analysis to check correlation between the discharge (Q) and stage (H). The mean values of the two variables were then adopted to fin...
Show More
Importance of Vertical Groundwater Flow as a Discharge Component in Transboundary Chotts, Western Tunisia
Ibtissem Yahyaoui,
Jose Joel Carrillo-Rivera
Issue:
Volume 10, Issue 3, September 2022
Pages:
56-64
Received:
19 September 2022
Accepted:
9 October 2022
Published:
21 October 2022
DOI:
10.11648/j.hyd.20221003.12
Downloads:
Views:
Abstract: The presence of groundwater discharge zones, locally known as Chotts, in the western border of Tunisia with Algeria is used as a case study to evaluate the current regional transboundary groundwater development status and the probable challenges of present groundwater trajectory, its regional flow patterns, water balance, and overall discharge-recharge features. The Tunisian Chotts Region constitutes the main discharge feature of groundwater flowing in the Continental Intercalaire and overlying Complex Terminal geological formations with their main recharge areas been claimed to be in the south Atlas Mountains of Algeria, the Tinrhert plateau of Algeria and the Dahar Mountains of Tunisia. The general direction of groundwater flow in the horizontal plane reaching El Djerid Chott is from West to East coming across the Algerian–Tunisian border seems to ensure hydraulic continuity of the Continental Intercalaire in the Djerid region. The affected territory covers some 7,000 km² with a surface elevation of 10 m amsl to –25 m bmsl; this land shears similar geographical location and elevation conditions as other chotts in Tunisia (ie., Gharza, Chtihatt Sighat, El Rahim, Majez Sfa). In the other side of the border, the main surface features in Algeria are characterized by chott Melrhir with 6,700 km² and –33 m bmsl, as well as the Merouane, the Kralla, Aslouj, Zhithif, Zebahir, Felrhir, out of which several are also located below main sea-level. A common feature from the groundwater perspective is certainly high salinity and water temperature as in Chott Gharza. Using Tóth’s theory on groundwater flow systems, surface indicators were further analyzed to understand the systemic connection between recharge and discharge zones of regional groundwater flow identified from evidence on the land surface. Results suggest the need of further reviewing scientific data as well as to design a widespread education and training in groundwater flow systems understanding aimed to an increasing international interaction with shared information and common objectives in the management of transboundary groundwater systems. Without adequate and accurate scientific knowledge of groundwater flow characteristics in its 3D distribution, uninformed policy development could lead to unsustainable groundwater management. Current transboundary groundwater assessments would improve through a more solid scientifically management international scale plan. A road map towards a shared management of groundwater is described aiming to promote equitable and responsible groundwater allocation.
Abstract: The presence of groundwater discharge zones, locally known as Chotts, in the western border of Tunisia with Algeria is used as a case study to evaluate the current regional transboundary groundwater development status and the probable challenges of present groundwater trajectory, its regional flow patterns, water balance, and overall discharge-rech...
Show More