Hydrogeological instability on the regional territory from 1979 to 2010
The three reports provide for each period considered a summary of the main landslide events that have affected the region, in terms of number, size and / or damage caused, associating events to weather conditions and in particular precipitation.
In the sequence of succession of events the reference period used is the hydrological year, identified from 1 October to 30 September of the following year, the period indicatively between the beginning of autumn rains (it is considered the factor of the movements) and the end of the following summer season when saturation conditions are usually at a minimum.
The choice of identifying the hydrological year as an analysis interval derives from the desire to follow, even though schematically, this "breath" of the slopes that is renewed, with some exceptions in periods with particularly humid summer or with a delay in particularly dry periods.
Starting from the data provided by the regional databases, respectively of the Regional Agency for Prevention, Environment and Energy (ARPAE) for the meteorological part, and of the Geological Seismic and Soil Service (SGSS) for the geological part, for every year hydrological is repeated a common descriptive scheme, with a schematic summary of the meteorological trend of the reference period, in particular in relation to precipitation, followed by a detailed history of the main landslide events that took place in that time interval .
The information related to the landslides reported mainly derive from press reports, technical reports, inspections of regional services and notes from other public administrations. The documentation has been reproduced in digital copy and stored in the historical archive of landslides of the Emilia-Romagna Region.
The historical landslide archive contains almost 12,000 documents referring to over 9,000 landslides that occurred on the regional territory from the Middle Ages until 2018.