Assessment of Bioswale Performance after Renovation and Ability to Collect and Store runoff in Altering Storm Conditions from Climate Change

Abstract

Increasing urbanization has created many opportunities for storm water runoff to accumulate in local water bodies thanks to an increase in the number of impervious surfaces. Green infrastructure methods like bioswales have been devised to solve the issues of flooding that can occur from these rainfall events; however, these events are becoming more numerous and stronger with the advent of climate change. The main campus of Purchase College has recently renovated the bioswale and updated it with new equipment and pipe structures. Rainfall events were analyzed to see how well the bioswale can perform after renovation and to assess the ability of the soil used in the bioswale to store water in relation to the changing storm trends caused by climate change. A total of 15 storms were analyzed from January 20th, 2023 to May 2nd , 2023 with only half of them producing periods where soil became moist, with three of these storms creating complete soil saturation. Excess runoff from precipitation could properly infiltrate and percolate through the soil. The soil was also properly dry for hours before the next major storm, although with delays between soil moisture responses averaging at 0.64 hours and 0.22 hours for deeper soil layers, this could factor towards the data's outcome. Five of the storms had instances where water appeared at the surface layer of the bioswale, and there were 13 extended periods where water in the drainage pipe of the bioswale was elevated which show that the discharge rates of the bioswale are in need of improvement.