Permeable Pavement as a Compensatory Technique in Urban Drainage in the City of Recife (PAP014803)

Código

PAP014803

Autores

Artur Paiva Coutinho, Jaime Joaquim da Silva Pereira Cabral, Antônio Celso Dantas Antonino, Suzana Maria Gico Lima Montenegro, Tássia dos Anjos Tenório de Melo, LARISSA VIRGÍNIA DA SILVA RIBAS

Tema

Flood risk management in mega cities

Resumo

In urban areas, increasing occupancy and waterproofing of the lots combined with the lack of environmental planning, has resulted in considerable increase in impermeable areas such as: roofs, streets, parking lots and others, which significantly alter the qualitative and quantitative features of the hydrological cycle. The consequence of this fact is the occurrence of unwanted discomfort urban problems such as flooding, rising temperatures, global warming and the degradation of rain water, and others. In the case of Pernambuco, the problem already exists in urban areas in the Metropolitan Region of Recife, which are very flat and low slope and for this reason, they present many problems of flooding, especially during May, June and July. Infiltration systems such as permeable pavements are presented as alternatives that allow the reduction of the peak and volumes of run-off hydrographs generated, allowing as well, a reduction of the pollution load, in addition to promoting the quantitative recharge of groundwater by infiltration. The aim of this work is the study of the use of the permeable pavement technique in damping flooding due to torrential rains in the city of Recife. The pavement was designed for a return period of 2 years and was executed in the parking lot of the Center for Technology and Geosciences of UFPE resulting in a section of 64 cm thick. The study consists of the monitoring, during two rainy blocks in the years of 2010 and 2011, variables with rainfall, daily water and automatic level of the reservoir layer of the pavement beyond the daily monitoring of matric potential of water in soil allowing to evaluate dynamics of the redistribution of infiltrated water. The coating and subgrade material soil were characterized using Beerkan methodology. Moreover, numerical simulations were performed for flow and dynamics of the water in the soil (subgrade) of the pavement using Hydrus 1 - D, analyzing run-off rainfall scenarios using project rainfalls based in the methodology of Bureau of Reclamation, rain with constant intensity for various return periods. Granulometry and parameters of the retention curve of water in soil, besides the potentials daily measured - characteristics of the soil of experiment - were used as input data. As results, it was observed that the coating layer showed infiltration features higher than the subgrade layer; some events presented overflowing, showing that the design methodology adopted has undersized the system, the water level in the reservoir layer showed high sensitivity to precipitation events. In addition, the pavement showed capacity to drain in less than 24 hours the volume, showing that it is able to receive the water intake caused by other events.