Relationship between rainfall and run-off In the Stratoni Region (N. Greece) after the storm of 10th February 2010

Abstract

Extreme floods often demonstrate unanticipated characteristics that pose problems for management and response. The flood in the Stratoni region in February 2010 provided an example of such unexpected response. The aim of this paper is the quantification of the hydrologic response of the torrents that outfall in the area of Stratoni of the prefecture of Chalkidiki by means of the synthetic unit hydrograph method. For this purpose, the effective rainfall is estimated with a Curve Number of Soil Conservation Service (SCS) procedure. In addition, the flood hydrograph is estimated using the Sierra Nevada's synthetic unit hydrograph procedure. The resulting maximum flood discharge was compared with the value obtained by the method of flood-water traces and found not to differ significantly. Understanding of the hydrological operation of floods in small watersheds helps towards the design of plans and constructions of the infrastructure against flood risk.

An integrated approach of flash flood analysis in ungauged Mediterranean watersheds using post‐flood surveys and unmanned aerial vehicles

“…Therefore, AMC is of higher importance than the forested area, because during extreme rainfall events the forest soil water retention capacity decreasing rapidly (Hegg, 2006;Schleppi, 2011). Recent studies in the study area indicate that Chalkidiki region is extremely vulnerable to flash floods, despite the considerable percent of forested area (Kastridis & Stathis, 2012;Kastridis & Stathis, 2017;Kastridis & Stathis, 2020;Sapountzis & Stathis, 2014;Stathis & Stefanidis, 2001;Stefanidis et al, 2007).…”

“…nerable to flash floods, despite the considerable percent of forested area(Kastridis & Stathis, 2012;Kastridis & Stathis, 2017;Kastridis & Stathis, 2020;Sapountzis & Stathis, 2014;Stathis & Stefanidis, 2001;Stefanidis et al, 2007).Concerning the urban sprawl, the comparison between the orthoimages of the study area dated back to 1945 and the recent orthoimages from 2007, showed that Olympiada settlement has been expanded on the floodplain of Mpasdekis main stream (Figure 2). It is evident that the alluvial fans of the floodplain were active back to 1945, the north part of Olympiada was built on the deltaic depositions of Mpasdekis stream and the riparian forest was clear cut.…”

“…In the past, the two streams have been flooded several times (October 2006, February 2010, September 2011, October 2014, December 2014, causing severe damages.…”

“…Chalkidiki region is one of the most vulnerable parts of Greece to flash floods, with the highest frequency of flood events (Diakakis, Mavroulis, & Deligiannakis, 2012). Therefore, several researches have described and evaluated the flood hazard of the area and have investigated the causes of the flash flood generation (Kastridis & Kamperidou, 2015;Kastridis & Stathis, 2012;Kastridis & Stathis, 2020;Myronidis, Stathis, & Sapountzis, 2016;Papamichail, Georgiou, & Karamouzis, 2001;Sapountzis & Stathis, 2014;Stathis & Sapountzis, 2003;Stathis & Stefanidis, 2001;Stefanidis, Kalinderis, & Tziaftani, 2007).…”

“…October 2006, February 2010, September 2011, October 2014, December 2014, causing severe damages.Based on the available meteorological data, the climate of the region could be characterized as typical Mediterranean one, with dry and warm summers and relatively mild winters. The precipitation is mainly distributed on Stratoniko mountain range, while the orographic effect of the intense relief causes rapid condensation of humidity and warm air masses, causing often and severe flash flood events.…”