Stormwater Attenuation Guide

Stormwater management is a major concern in cities because due to impervious surfaces all around, the stormwater does not get absorbed by the soil. In a natural setting, most of the rainwater is soaked by green plants and soil. And, the rest water is flown to the nearby water bodies through the natural waterways. However, in cities, this process has been disturbed which results in an imbalanced hydrological system, flooding, and water pollution. While most cities comprise a stormwater drainage network that works well to divert the stormwater from the source point to the nearby water bodies, it fails to prevent water pollution. As storm drains do not comprise any water filters, they fail to check the pollutants from entering the water bodies. Although government and municipalities work towards mitigating water pollution, as a citizen, we can implement numerous ideas in this regard. Here, we have shared a few of them. 1) Install a stormwater attenuation system A storm

While we all love rain as it has a special soothing effect, heavy rainfall is the cause of many problems in cities. Due to the abundance of impervious surfaces all around, the rainwater does not find a way to seep into the ground. While the stormwater drainage network channels the rainwater from their source point to the nearby water bodies, it does not prevent flooding in case of heavy rainfall. A flood can damage social infrastructure facilities, homes, and businesses. Also, as rainwater carries away everything that comes in its way, it is the main cause of nonpoint source pollution . When stormwater runoff picks up oil, grease, metals, and pesticides from various places and rushes into nearby storm drains, it finally pollutes water in streams, lakes, rivers, and bays. Pollution from stormwater disturbs the aquatic ecosystem. Plus, this water becomes unfit for consumption and causes many water-borne diseases, such as botulism, cholera, E. coli infection, and amoebiasis.

We all love rain and its musty smell as there is something very soothing about it. But heavy rainfall can be a problem for urban areas because it might cause waterlogging. In a natural setting, rainwater is absorbed by the soil and is drained away through natural waterways. But in cities, due to the scarcity of pervious surfaces, the natural rainwater management system does not work properly. Therefore, all the millions of gallons of water that tumble onto the ground do not find a way to reach the nearby water bodies and recharge the water table. While the urban stormwater management network tries to prevent waterlogging by diverting the stormwater runoff from the source area to the nearby water bodies, this system fails in case of heavy rainfall. Another problem with the urban stormwater management system is that it does not check the flow of dirt and pollutants which causes water pollution. After all, the runoff is incredibly good at picking up whatever comes into its way.

Rapid urbanisation has contributed to increased impervious surfaces that have altered the natural hydrological cycle. Therefore, rainfall that used to directly infiltrate through the soil or slowly drain through natural waterways now runs off the concrete surfaces. Although urban stormwater networks can easily manage runoff from low to medium intensity rainfall events, they fail to transfer excessive runoff from heavy rainfall events. In case of heavy rainfalls, we need to rely on overland flow paths which include natural rainwater drainage paths based on the topography of the land. But many times, they get blocked, thereby causing flooding. Waterlogging or flooding not just destroys public and private properties, but also causes water pollution. To prevent these situations, it is best to install stormwater attenuation tanks . These tanks rely on the concept of storing stormwater close to where it falls and slowly releasing it back into the stormwater network after the flood peak

Heavy rainfall is sometimes a cause of concern for cities. In the scarcity of natural pervious surfaces, sometimes it causes waterlogging and flooding. Moreover, due to the absence of a natural water management system, rain falling on streets, rooftops, sports fields, and other impervious surfaces may carry away pollutants and discharge them to the nearby water bodies. The stormwater may carry away the following pollutants Fertilizers and pesticides from gardens Pet wastes Dirt and debris from construction sites Petrol, grease, accidental spills, land leaky storage containers In most cities across the world, storm drains do not comprise any feature for filtering the stormwater before discharging it into the water bodies. Why is stormwater pollution a problem? Stormwater pollution has affected the quality of freshwater in rivers and streams. This polluted water is not appropriate for drinking and when consumed, it may cause several diseases. It is costly to