A study by the University of Granada has revealed that the rainwater collector that was installed to channel the waters of the catchment basin into the original bed of the Barranco del Canalillo is of "insufficient diameter", causing it to overflow from its original course.
This is stated in a report commissioned by the City Council of Atarfe, to which Granada has now had access, which details part of the reasons why flooding occurs in some neighbourhoods of the metropolitan area and what the consequences would be in specific circumstances depending on the rainfall.
Thus, in the conclusions of the hydrological and hydraulic modernisation carried out, it reflects that to date various hydrological studies have been carried out with the Canalillo ravine as the subject, although "none included an adequate study", which is why the UGR technicians consider them to be "incomplete".
Thus, it is considered that the original course of the Barranco del Canalillo ravine as it passes through the town of Atarfe "has been modified on numerous occasions" as a result of various urban development actions carried out, "to the point that currently no properly marked course can be recognised that serves to channel the waters of the catchment basin".
However, the report does recognise that a rainwater collector was installed to transport the flow associated with the catchment basin, although it turned out to be "of insufficient diameter", and this system was integrated into the rainwater network of the urban centre.
The study concludes that the flow of the Barranco del Canalillo overflows from its natural course "even before it reaches the existing facilities for the diversion and channelling of the ravine, so that the efficiency of these facilities would be reduced in the event of a hypothetical flood".
Insufficient to collect flow ratesInsufficient to collect flow rates
These flow diversion facilities as well as the 1,000 mm diameter pipe behind the manual gate are "clearly insufficient to handle the calculated extreme flows".
Similarly, part of the urban area and various sectors of the undeveloped plan "are affected" by the floods associated with the different return periods, so that in order to guarantee the proper behaviour of the drainage system it is "necessary" to undertake its resizing as well as to propose a maintenance plan for the cleaning of the channels and pipes "that maintains their evacuation capacity intact.
The study of the Barranco del Canalillo has been carried out by GIS4tech Sistemas de Información Geográfica aplicados a la Ingeniería y al Urbanismo S.L., a spin-off of the University of Granada, which is currently working on alternatives to find a solution to the drainage system that will prevent flooding in the future.
Atarfe Town Council has requested another study on the Barranco de la Cañada with the aim of registering it before December 2018 with the Regional Ministry of the Environment and for it to be included in the Plan for the Prevention of Floods and Floods in Andalusian Urban Watercourses (PCAI). Its purpose is to carry out the necessary infrastructures to avoid situations such as those experienced last Friday.
On the other hand, the Town Hall of Atarfe has informed that from Thursday the office for those affected by the storms will be open from 08.00 to 15.00 hours in the Mayor's Office.