Applying the Parameter “Irreducible Concentration” in Modelling of Stormwater Treatment Facilities

• 作者: Anna Wahlsten Thomas Larm
• 来源期刊: 土木工程与建筑:英文版
• 学科: 数学
• 关键词: IRREDUCIBLE CONCENTRATION STORMWATER treatment swale wet POND wetland BIOFILTER
• 年，卷（期）: 2019,（8）
• 页码范围: 469-476
• 页数: 8页
• 分类号: O15

摘要

To design stormwater treatment facilities (STFs), we recommend the use of a model that should include the calculation of runoff quality, to be based on a detailed land use specification, include site-specific design parameters, calculated outflow concentrations and loads of specified pollutants of relevance for the receiving water. This study compiles minimum outflow concentrations from stormwater databases of different types of STFs (e.g. swales, wet ponds, wetlands, biofilters and underground retention basins with filters). These data are used for the suggested values of specific “irreducible concentrations” (Cirr). Suggested Cirr for phosphorus (P) varies from 20-82 μg/L depending on facility type, for copper (Cu) 1.1-3.7 g/L, for zinc (Zn) 2.0-17 μg/L and for total suspended solids (TSS) 2,900-5,700 μg/L. Corresponding data for 70 substances are compiled in the StormTac database and employed in the model StormTac Web. Cirr has significant impact regarding the choice of facility type and its calculated dimensions. This design parameter and the calculated outflow concentrations can be used to investigate the need for combined serial facilities or complemented design elements with more planted vegetation or installed filters. Such elements can be required to decrease Cirr and thereby reach project specific limit outflow concentrations and loads.