RELAÇÃO ENTRE TIPOS DE TEMPO, EVENTOS DE PRECIPITAÇÃO EXTREMA E INUNDAÇÕES NO ESPAÇO URBANO DE SÃO SEPÉ –RS

Abstract

The research has have the objective of relate the extreme stormwaterprecipitation events with the ocurrence of floading at the São Sepé city urbanarea, at the period from 1980 to 2006. In order to analyze the time-spaceprecipitation on the urban area, as well as its seasonal variation. It was decidefor the instalation of four rain gauges, made by craftwork form. The datascollects from the rain gauges were made between the period of one year andwas chosen the most representative mounth of each season as sample. Throughthe datas crossing of the extreme stormwater events reported by local presswere chosen seven floading cases which had the most impact at the urban area.Using as parameter the cases analyzes was noticed the level of precipitaioncapable of criate this sort of impact is at least 38 m m noted in 24 hours and thelarge precipitation volume noted in 24 hours was 121,8 m m . The intensity ofprecipitation check that the floading only occur when the the precipitations arefrom averages to strong or with an intensity upper ( strong and stronger) . Theaverages precipitations are susceptible of causing floading only if followed ofminor intensities. The floading could been distributed in three groups accordingthe episode beggining ; floading conected to fast frontal passages; floadingconected to local fronts and floading conected to the acting of joint tropicalsinstability and pollars fronts. As much as the floading repercussion of urbanarea, all the cases analyzed ocurred damage as like as the invasion of houses bythe water causing homeless people, besides material damages like total orpartial lost of property and bridges and also the danification of rubans ways.Finally, was look forward to establish the susceptibles areas to floading as wellas that aeras that might been reached by floadings in measure the urbanizationgrows.