Peri-urban areas, morphological evolution and hazards: The case of Rio city, Northern Peloponnese, Greece

Abstract

Morphological evolution and its relationship with peri-urbanization is becoming an increasingly interesting and significant topic, due to the high impact that it has on highly sensitive areas.

Our study area is the city ofRioin northern Peloponnese is located approximately 7 km from the city ofPatras. With a population of around 15.000 people, is considered to be a highly sensitive area, because of numerous and important infrastructure, such as the University of Patras, the local University hospital, two sports halls and the Ottoman era fortress located at the coast.

The geology is characterized by the formation of Olonos – Pindos zone, including Pliocene and Pleistocene sediments, covered by quaternary and alluvial deposits and faults of NE-SW and NW-SE direction.

Geochronological and sedimentological studies of dated raised terraces found an average uplift rate of 0.4 to 6 mm/yr while the dating results indicate pre-Tyrrhenian to Tyrrhenian interglacial ages.

Hydrologically, the area is characterized by ephemerous streams and rivers such as Charadros, Selemnos, Volinaios and Foinikas flowing into both theGulfofPatrasandGulf of Corinth. The area combines sectors of mixed use. Green parts are also present in a currently developing area.

During the years, the area has undergone a series of changes that can be developed into potential hazards. The construction of Patras University in the 1960’s and the University hospital in the late 1980’s led to the infilling of one branch of Selemnos river, increasing the risk of flooding of the remaining river branch.

The coastal area suffers from erosion introducing risks to the port and coastal infrastructure. Some minor remediation works were unsuccessful.  Combined with the high seismicity of the area, the extensive human intervention, high seismicity and the local tectonics, introduce risks that have to be researched, studied and controlled.