The paper “ The Goodness of Fit between the Observed Predicted Flat Flows, the Reliability of Models for Predicting Future Flood River Flows” is an informative version of the statistics project on environmental studies. Flooding can be very devastating if the proper prediction is not carried out using modeling techniques that are accurate. The models adopted in flood prediction should be able to accurately predict the volume of water that will be flowing during heavy rainfall, determine base runoff as well as direct runoff. To begin with, determining peak runoff rates, as well as runoff volumes, are essential in the models that are used as a simulation of flooding.
This is information can also be used in designing water and soil conservation in flooding areas. The base flow and direct runoff information are usually recorded from the area of study and calculated from automatic recorders that are put there. This paper is going to study flood mathematical models that are used in flood modeling. 3.1 base flow and direct runoffUsing the data provided, the observed data event has been separated base flow and direct runoff separately.
This has been done to provide losses associated with the rainwater. In determining the base flow, it is assumed that the gradient does not affect the base of the river. This is comparable to the dry season when the flow rate is different. If we look at the initial SDM one can note that a small change leads to an increase in flow rate per second. When the base flow model is applied to simulate an event, the total flow is not known until after the base flow has been simulated and added to the direct runoff hydrograph. The rainfall/runoff model treats each catchment as a single unit, allowing some of the model parameters to be evaluated from physical catchment data.
The direct runoff model shows the SDM as well as the actual evapotranspiration and the runoff components such as interflow, base flow, and overland flow. This shown below From the figures above the discharge shows that cease to a high flow was a common occurrence period under study and not month that does not high flow rate. This is supported by the figure below for the month of January 1972. Justification of choice of method for separation and lose evaluation SDM contribution to flood flow is not at the same rate as surface runoff thus it is separately analyzed which is done as a requirement in hydrograph analysis.
The groundwater recession curve is a characteristic of the particular catchment in which it was recorded, and some part of this curve will be a constituent of the total hydrograph. If individual storm recession curves are fitted together to form a composite curve, the result is a master recession curve.
The recession curve has a continuous discharge record covering event 2291. It represents the base flow contribution after surface runoff has ceased, at as many different stages as possible.
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