Dam Hazard Classification using ENTRO Guideline in the case of Fato Dam, Ethiopia
| dc.contributor.advisor | Netsanet Nigatu (PhD) | |
| dc.contributor.author | Firaol Chalchisa | |
| dc.date.accessioned | 2023-12-14T14:51:09Z | |
| dc.date.available | 2023-12-14T14:51:09Z | |
| dc.date.issued | 2023-07 | |
| dc.description.abstract | The phenomenon of spontaneous breaches of dams and consequent flooding that have occurred throughout history have made it necessary to design dam safety plans and hazard management measures. In this case, the preliminary job was analyzing the dam breach before the event and ranking these dams based on risk. The pre-event analysis of a dam breach scenario for the Fato dam was the focus of this thesis. A deterministic approach is applied to model the dam breach. The extent of the resulting flood inundation is mapped and overtopping, and piping failure scenarios are evaluated. The upstream boundary condition comprises a 2.3*PMF inflow hydrograph and a base inflow hydrograph, and the downstream boundary condition is made up of a riverbed slope assuming the bed slope and energy grade line slope are equal to HAEC. The main reason why the PMF flood to overtop to dam needed is large is that a large freeboard is provided for the Fato dam about 3 meters here between the spillway crest and the dam crest. Seven 2D simulations were run, five of which are for various overtopping failures and two of which are for piping failure modes. HEC-RAS Version 6.3.1 hydraulic modeling software is used. Furthermore, seven deterministic non-physical empirical are assessed and compared. The five deterministic non-physical empirical methods have resulted in peak flow values between 32,940.26m3/s and 22,404.28m3/s for overtopping and two of them were 20,224.88m3/s and 11,799.72m3/s for piping modes of failure, respectively. Of the failures, overtopping failure generates the biggest peak discharge, which is 32,940.26 m3/sec using Von Thun & Gillete Equation. Not only the peak discharge results from this equation but also the flood reach to Guder Town is short for it, which is 1.35Hrs. Guder town is the focus of the study since most of the population at risk was situated in this town. Based on this flood inundation map the possible people at risk (PAR) were found to be 9,425 people. And based on the DSO-99-06 manual the Loss of life is found to be 4,713. The study found the dam breach and its corresponding flooding to be catastrophic in Loss of Life therefore its categorized as a very high-hazard dam based on ENTRO guidelines. The author also checks for the level of reduction if EAP is introduced, and the Loss of life is found to be only 10 people. Therefore, the study highlighted the provision of EAP to this dam will reduce the possible loss of life in case the dam fails. Taking this dam as a case study recommended the need for a national-level regulatory framework for different levels of dam life (Design, Construction, Filling, Operation, and Decommissioning). | |
| dc.identifier.uri | http://etd.aau.edu.et/handle/123456789/995 | |
| dc.language.iso | en_US | |
| dc.publisher | Addis Ababa University | |
| dc.title | Dam Hazard Classification using ENTRO Guideline in the case of Fato Dam, Ethiopia | |
| dc.type | Thesis |