How Markham Square will improve water quality

The first hour of urban storm water runoff can have a higher pollution index than raw sewage.

Treatment drains help to prevent this by diverting large volumes of water and deterring pollution buildup. Leveraging treatment drains and storm water management techniques utilizes low impact development and a network of green infrastructure to control both water quantity and water quality.

How it works:

  1. After a rain event water begins collecting in the street where it picks up pollutants and solid waste such as litter and core sediment.
  2. As it overflows into the rain garden closest to the vehicular roadway, storm water passes through the primary treatment and infiltrates into the ground.
  3. The water that doesn’t infiltrate continues to flow through green space and permeable pavement where it gradually seeps into the soil purifying and cooling the rain water along the way.
  4. By the time water makes it to the second rain garden both evapotranspiration and infiltration are working to absorb the rain water and feed it back into the natural water cycle.
  5. Lastly, any storm water that wasn’t collected will pool into the uniquely constructed creek bioswale where it flows until it reaches the watershed downstream.