Usage
  • 31 views
  • 50 downloads

Laboratory Study on the Hydraulic Performance of Bioretention for Stormwater Management in Cold Climates

  • Author / Creator
    Li,Zhan
  • Bioretention has shown effective stormwater peak flow and volume reduction in warm and temperate climates. However, the applicability of bioretention for successful stormwater management in cold and semi-arid regions such as Edmonton is still not well understood. Four large bioretention columns were designed for this study and set up in a temperature-controlled laboratory with the capacity of lowering temperature to – 20 °C. Designed storm events were applied and monitored for 1st summer operation, one winter exposure and 2nd summer operation. Synthetic stormwater was applied weekly in summer conditions to investigate the hydraulic performance of two different soil types, with and without an internal water storage layer. Column 1 and Column 3, with less porous soil media (50.8% sand, 29.4% silt, and 19.8% clay), were shown to effectively attenuate peak flow for 1:2 year events, with a mean peak flow reduction of 83% and 91% respectively in 1st summer, and 77% and 73% respectively in 2nd summer. Column 2 and Column 4, with more porous soil media (67.2% sand, 19.6% silt, and 13.2% clay), maintained high hydraulic conductivity (9.6 cm/hr and 9.1 cm/hr respectively) after 2nd summer operation. Under winter conditions, columns with more porous soil media retained more volume of water within the columns, took less time for soil thawing and water breakthrough, and ponding vanished faster over frozen soil than columns with less porous soil media. After columns underwent an extreme winter condition of columns frozen at 20 °C air temperature three times, their hydraulic performance was able to rebound quickly. All columns successfully managed 1:2 year events in terms of the infiltration rate, ponding depths and durations. Preliminary results also showed that both less and more porous soil media have the potential to accept and drain the less frequent, large volume events (1:5 and 1:10 year events).

  • Subjects / Keywords
  • Graduation date
    Spring 2019
  • Type of Item
    Thesis
  • Degree
    Master of Science
  • DOI
    https://doi.org/10.7939/r3-9mx0-mj63
  • License
    Permission is hereby granted to the University of Alberta Libraries to reproduce single copies of this thesis and to lend or sell such copies for private, scholarly or scientific research purposes only. Where the thesis is converted to, or otherwise made available in digital form, the University of Alberta will advise potential users of the thesis of these terms. The author reserves all other publication and other rights in association with the copyright in the thesis and, except as herein before provided, neither the thesis nor any substantial portion thereof may be printed or otherwise reproduced in any material form whatsoever without the author's prior written permission.