In the last 20 years, Natural Engineering and Biotechnology techniques have been used mainly in
European countries, the United States, Australia and more recently in China. Studies show that these
techniques, which were widely used in the past, are resurging more intensely, since they are important
tools in the civil engineering and river engineering, and are efficient, contributing to the process of requalification
of rivers and in a processes of reduction of floods. The Macaé River, the main river of the
Macaé and Oyster Basin, located in the northeastern part of the state of Rio de Janeiro, underwent a
rectification of its layout between the years of 1940 and 1980. Nevertheless, the municipality of Macaé
continues to present recurrent problems with flooding in scenarios of heavy rains. Through a
descriptive-exploratory research, a bibliographical review was carried out to identify alternative
techniques and materials in the areas of civil construction and bioengineering that presented
sustainable solutions to compose a proposal for intervention in the sense of river requalification. In a
second moment from the environmental diagnosis, an attempt was made to study a section of the
rectilinear channel of major interest. The preliminary analysis was developed using solutions based
on nature. The pilot project was developed with a cost estimate for the execution of the intervention,
in order to allow the restoration of the river in a more natural way, and to increase of the roughness
coefficient in the floodplain region in the order of 0.03 for 0.15 without to cause major impacts to the
local environment, including in the landscape.
Keywords: Natural Engineering. Biotechniques. Flood plain. Cost analysis.