๐ฑ๐ฟ Green Infrastructure as LID Controls ๐ฟ๐ฑ
SWMM empowers engineers and urban planners with the ability to incorporate green infrastructure practices as low-impact development (LID) controls, aiming to efficiently manage runoff. ๐ง️๐ง These eco-friendly practices also play a crucial role in reducing pollutants. ๐๐ซ
๐ฑ Bioretention Cells (or Bioswales) ๐พ Bioretention cells, essentially vegetative depressions, are crafted with a blend of engineered soil, positioned atop a gravel bed. They serve as reservoirs, facilitating the infiltration, storage, and evaporation of both direct rainfall and runoff from adjacent regions.
๐ฃ️ Continuous Permeable Pavement Systems ๐ง️๐ง Pavements designed to be permeable allow immediate passage of rainfall through them, directing it to the gravel storage layer beneath. This facilitates natural infiltration into the local soil. In block paver configurations, the gaps between blocks capture rainfall, guiding it to the storage and native soil layers below.
๐ข๐ฑ Green Roofs ๐ฟ Green roofs are akin to bioretention cells, characterized by a soil layer placed over a specialized drainage mat. This mat directs excess rainwater away from the roof. Additionally, their vegetative cover promotes rainfall infiltration and water evapotranspiration.
๐ณ️ Infiltration Trenches ⛏️ These are narrow, gravel-filled ditches designed to intercept runoff from adjacent impervious terrains. They offer storage volume and prolong the time for runoff to infiltrate the underlying native soil.
๐ง️๐ข️ Rain Barrels or Cisterns (Rainwater Harvesting) ๐ง Rain barrels and cisterns, essentially storage containers, are instrumental in collecting rainwater during storms. They can either retain the water for later use or release it during dry spells. Cisterns, with a more expansive storage capacity, can be positioned either above or below the ground.
๐ผ Rain Gardens ๐ธ Rain gardens, characterized by their recessed nature and vibrant vegetation, accumulate rainwater from various sources, promoting its infiltration into the ground. The more intricate versions of rain gardens often resemble bioretention cells.
๐ Rooftop (Downspout) Disconnection ๐ง️➡️๐ฟ This eco-friendly method redirects rainwater from rooftops to permeable terrains, such as gardens and lawns, instead of directing it straight into storm drains. It can be utilized to store stormwater (like in rain barrels) or enable its infiltration into the soil (like in rain gardens).
๐พ Vegetative Swales ๐ฟ Vegetative swales, essentially channels or recessed areas enveloped in grass and other greenery, decelerate the flow of collected runoff. This gives the water ample time to infiltrate the soil beneath.