As tens of thousands of Rio de Janeiro based families in the Serrana region begin to pick up the pieces of what was a horrific start to the new year, serious questions remain as to how the floods had such a catastrophic effect and, indeed, what direct measures need to be made to prevent such events from occurring again.
Shortly after the disaster, a group of professionals from the Rio de Janeiro Council of Engineering, Architecture and Agronomy (CREA-RJ) spent time with key figures involved with infrastructural improvements in the main areas hit – namely Teresópolis and Nova Friburgo – with a view to adopting strategies to ensure such a magnitude of unfortunate circumstances cannot happen again.
One of the essential requirements was controlling the flow of the rivers in the region – a debated methodology would be to install dry stone blocks with heights ranging from 0.5 to 1 meter.
Another potential solution discussed was the construction of a series of underground ditches which would effectively trap runoff water. As a complementary measure, a number of hydraulic systems would be strategically located along the general direction of the river flow to control any accumulated water.
With regards to the management of the heavy rains that the region experiences annually – the group proposed to construct a retention basin via the formation of a guttering and draining gallery network.
Additionally, a series of sediment traps would be created to manage the issue of soil erosion – which could have a complementary role of serving as recreational areas and sports fields.
CREA-RJ further highlighted the need to construct reservoirs and dams in the middle and upper wider stretches of the river in order to minimize the effects of waves caused by the rains as well the accumulation of debris which changes the flow of water.
During the relief effort, one of the main criticisms was the lack of good access in order to help those most in need. Brazil’s roads and highways remain significantly below standard and, whilst efforts are being made to improve the situation such as via the Growth Acceleration Program (PAC’s) funding, a considerable amount of work is necessary.
In the region, plans were announced to restructure all of the roads and pathways accessing the affected areas; reconstruct bridges and recover all urban infrastructure as well as undertake in detailed structural assessments of the buildings destroyed.
On a national level, several environmentalists, planners and geologists have argued for a legislative change with the law related to property construction on slopes which should not be permitted on gradients of over 22 degrees – illustrating that there is clear evidence of landslides occurring at 30 degrees, especially in regions of high humidity and rugged topography.
Of most concern, however, is the need to ensure that any proposed measures are acted upon and not just left for discussion – with many pointing to the fact that similar events in the same state in the same period of 2010 (whilst not as severe) should have taught some clear lessons on the vulnerable situation that heavy rainfall in Brazil creates.
Ruban Selvanayagam is a Brazil real estate and land specialist. For free e-books, state guides, up-to-date statistics, strategies, interviews, articles, weekly broadcasts and more head to the Brazil Real Estate and Land Investment Guide via the following link: http://www.brazilinvestmentguide.com/brazil-property-real-estate-land/