Juan G. R. Major flooding in urban areas of Spain, warning about the deficiencies in the drainage systems.
Water and Irrigation, Volume 1, Nº1: 3-4, 2010, Spain.
Major flooding in many cities in the Andalucia Community and the island of Tenerife belongs to the Canary Islands and with less intensity in Valencia, the Balearic Islands, Aragon and in the Communities of the north, has caused the entry into Spain of different cold fronts and disturbances, which have been accompanied by heavy rainfall, events that occurred during the months of January and February 2010 and the end of 2009. As a result of heavy rains there are many agricultural areas affected by floodwater. Analyzed precipitation for the period of December, January and February are considered very high, with a significantly accumulate value in the period 2001-2010.
In the regions most affected by the floods, the volume of low and medium reservoirs delivery capacity are near to maximum capacity, but not the large dams still allowed to retain more water, however has been strategic to free water in several reservoirs , which shows that it is necessary to build a larger number of reservoirs of medium and low capacity and sometimes build dams that will enable greater capacity to mitigate the impact of floods and to retain water during periods of rain , to cope with the demand for water during periods of severe drought. It is also helpful to have more transfers that carry the water from areas with sufficient water resources to other regions with water deficit.
Such variability of climate: cold front from the Arctic, Siberian cold front and the entry of Atlantic disturbances with abundant rains in the southern region, has revealed that the network of internal and external drainage in urban areas, the systems drainage from agricultural areas, are insufficient to cope with high intensity rainfall, even more if there are rivers overflowing with insufficient infrastructure to lessen the effect of flooding, cut roads and the need to rectify some rivers, dyke protects some areas protection. It is essential to increase the capacity of networks of internal and external drainage in many cities and in agricultural areas, to reduce the large economic losses and human lives that cause these unfortunate events.
The flooding problem becomes more critical if we take into consideration, inappropriate urban planning that has allowed build buildings, homes and businesses in low lying areas and on former water channel without making the recommended protective works to counteract the effect of floods, causing greater damages. We also noticed that many roads not have an adequate hydrological study, so it is necessary to increase the number of drainage works in order to protect them from the effect of flooding, on several occasions acts as roads dam, increasing the time of the flood affected areas. Proper planning of measures to take in each autonomous community and plan to make investments in flood control enables that the material damage and human losses are reduced considerably.