Bioretention cell efficacy in a cold climate

最近，行业专业人士开始实施低影响开发(LID)，作为控制径流量、补给地下水和通过在源头拦截和处理径流来改善水质的一种方式。盖子的一个很有希望的例子是生物延伸器。这些是土地上植被茂密的洼地，通常放置在停车场和交通岛上，用于捕获和处理雨水径流。污染物负荷的长期影响及其对渗滤率、去除效率和生物滞留系统的影响还没有得到广泛的研究。此外，关于季节对生物滞留性能的影响的研究很少，特别是在加拿大部分地区占主导地位的寒冷时期和冻融循环期间的效率。这项研究将确定在春季淡水期、夏季期间和秋季冻结期间，生物缓释细胞在减缓雨水水位方面的有效性；并确定这些细胞在季节性条件下去除系统出口的总悬浮固体(TSS)、淋滤或保留磷、氮(以各种形式)和氯离子的有效性。这些信息将传播给在寒冷和温带气候下负责缓解暴雨的市政当局。这将有助于他们提供更好、更具成本效益的盖子设计。

More recently, industry professionals have started to implement Low Impact Developments (LID) as a way of controlling runoff flow volumes, recharging groundwater and to improve water quality by intercepting and treating runoff at the source. One promising example of an LID is a bioretention cell. These are densely vegetated depressions in the land, commonly placed in parking lots and traffic islands, which capture and treat stormwater runoff. The long term impacts of pollutant loading and its effect on infiltration rates, removal efficiencies and on the bioretention system have not been widely explored. Furthermore, there has been little research into seasonal effects on bioretention performance, especially the efficiency during cold periods and during freeze-thaw cycles that are dominant in parts of Canada. This research will determine the efficacy of bioretention cells for attenuating stormwater hydrographs during spring freshet, during the summer, and during freeze-up in fall months; and determine the efficacy of these cells for removing total suspended solids (TSS), for leaching or retaining phosphorus, nitrogen (in its various forms), and chloride ions from the outlet of the system over seasonal conditions. The information will be disseminated to municipalities charged with stormwater mitigation in both cold and temperate climates. This will help them to provide better and more cost-effective LID designs.