Thesis Title:  «Flood Risk assessment and Flow modeling of the Stalos stream area»

Thursday  19 December 2019, at: 14:30, Venue: Hall Κ2A11

Examination Committee

• Professor  George Karatzas (advisor)
• Professor Nikolaos Nikolaidis
• Associate Professor Nikolaos Paranychianakis

Abstract

In this thesis the main goal was to assess the Flood Risk of the area of Kato Stalos, located just West of the city of Chania in Crete, in 2 stages. The first stage is the spatial assessment of the study area’s flood risk by use of Geographical Information Systems software (GIS), based on 6 main factors: Altitude, Slope, Flow Accumulation, Hydrogeology, Land Use and Spatial Distribution of Rainfall Intensity. The aforementioned 6 factors were quantified on a same-basis scale by creating raster maps, and subsequently utilized in the calculation of the total Flood Risk of the study area, by being spatially combined with a weighted coverage method.

The second stage of the study was to model a stream located within the study area and that is also located near previously recorded flood events. The stream that was modeled in this thesis originates from just South of the village of Ano Stalos, merges with another substantial branch and its estuary is in the North of the study area, in the locale of Kato Stalos. The installation of both a meteorological logging and transmitting station in Ano Stalos, as well as a water level logger and transmitter in the lower estuary part of the stream enabled the acquisition of real and recent data, which was subsequently used to construct a 1-D flow model in the MIKE software suite, with the MIKE HYDRO River module, in addition to recording stream cross sections and their digitization through the ArcGIS GIS Software suite.

The implementation of the aforementioned methodology lead to the determination of the spatial Flood Risk of the Stalos area in Chania for the current situation, as well as the future, by taking into account the newly designed Civil Plan which is expected to be implemented in the near future and includes an expansion of built areas. In addition, the behavior of the stream during heavy rain events was assessed, and it was determined that the flood risk of the adjacent to the stream areas was relatively low, as the water level never reached nowhere near dangerous levels, despite heavy rain for extended periods of time.