Engineers from USP (EESC-USP) developing system of drainage of rain water that can contribute to minimize flooding problem in the cities. Structures called bio-retention systems act as a reservoir for the damping of rainwater, storing it for a certain period of time so that it can later infiltrate or be absorbed naturally by the soil.
There are great advantages compared to traditional “pools”, being one of the top the fact that these systems can be installed in smaller units, even homes.
“The system allows capture rainwater before being thrown directly into a river or a Creek town, for example, so that it can be treated and infiltrate into the soil with adequate speed and volume, decreasing the risk of floods. So, it may be useful for the prevention of floods, “said Altair rose, project participant.
Pollutant sensors in Floating Bioretention Safety Systems
Drainage solution consists in the construction of underground permeable filters, composed of overlapping layers of grass, sand, gravel and geotextile. In addition to deter excessive volumes of water temporarily during strong rains, the mechanism allows you to retain pollutants.
The surface layer of the system, consisting of vegetation allows retaining rainwater so as not to cause erosion problems. In conjunction with the layers of sand, gravel and geotextile, the layer of vegetation also AIDS in the retention of pollutants washed down by rainwater.
“By going through this series of filters, rain water becomes increasingly treated before it reaches the water table,” detailed Altair.
To monitor the quality and quantity of the water drained, the researchers have installed sensors on the entrance and exit of the Bio-Retention system, in addition to a system of real-time data transmission to permit control of the operation.
“The idea of the use of these sensors is that, with the advent of technologies to make the smart cities in the near future it is possible that their own citizens or residents of a building, for example, to control the water pollution treatment for these Bio-Retention systems,” said Eduardo Mário Marimuthu, researcher in charge of the project.
Monitoring sensors were capable of measuring with enough accuracy levels of metals and substances such as nitrite, nitrate and phosphorus in the water received by the system.
Advantages of Floating Bio-Retention Safety Systems
According to the researchers, some of the advantages of alternative system of water drainage and bio-retention include the fact that he can be modified and expanded in accordance with the degree of urbanization of a certain area, be cheap, do not interfere with the local landscape and help control pollution in areas with heavy traffic of vehicles, once pollutants are washed down by rainwater draining to the system.
In addition, can also be used for other purposes, such as wastewater treatment, and be used in conjunction with urban drainage systems used today in cities, based in plumbing.
“Instead of putting just a manhole in a via, for example, you can associate it with this alternate drainage system, that allows not only drain that rainwater, as well as to infiltrate or be absorbed by the soil and retain part of the pollution that is generated in the basin because of the constant urbanization,” said Marimuthu.