Magical Concrete absorbs water
Combine Sewer Overflow is a sewage collection system for pipes and tunnels designed to collect surface runoff and sewage water in a shared system at the same time. CSO can cause serious water pollution problems. CSOs occur more often in heavy rain and snowmelt, and heavy rain incidents have increased 70 percent in the past 60 years, which means the old drainage system may not support the rainstorm. It is almost impossible to dig out all the pipes and rebuild the drainage system, it needs some new technology to help the city to store the stormwater.
Normally, road paving material is made of a mix of fine crushed stone or for paving. Even though more and more cities began to adopt porous asphalt to reduce the volume of stormwater, porous asphalt has limitation that it is too weak for high traffic areas. A UK company has developed a permeable pavement that can drink 1,000 liters of water per square meter in a minute. This kind of permeable concrete is installed on top of the soil that the fine crushed stone or sand is not needed for paving. Rainwater drains through the top surface, collects in the aggregate layer, and is slowly released into the ground.
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