Experimental Rehabilitation of Three Concrete, Urban Stretches Streams Through Biophilic Interventions Designed: Environmental Evaluations

In this study, we assumed that river rehabilitation refers to a set of ecological and managing actions aimed to recuperate the natural conditions of a river system to sustain biodiversity, permit recreational uses, manage floods, and conciliate the landscape progress. Through this study, we intended to understand the hydrological- and water quality–related variables of three urbanized catchment areas, as well as evaluate the achievement of in-stream biophilic structures previously designed and installed to possibly mitigate the degradation status of such river stretches. In three urbanized rivers located in Sorocaba, SP, Brazil, we conducted, biweekly and during 2 years, the analysis of a set of water quality parameters. In the first year of samplings, we did not implement any kind of intervention in the stretches. After this period, we analyzed the data and the hydro-ecological features of each stretch. Hence, we designed and installed structures aiming to test the efficacy in terms of water quality improvement. We analyzed the effectiveness of each kind of intervention using a multiparametric index called the “Difference Index of Water Quality”—DIWQ. As the main results, we state that two of the three interventions presented a satisfactory performance in terms of improvement of water quality. However, we conclude that it is very difficult to rehabilitate rivers without the removal or reduction of the actual impacts uphill. Hence, we emphasize that a set of complementary actions, divided into two subgroups, should be implemented.