Media Filter Drain: Modified Design Evaluation and Existing Design Longevity Evaluation.

摘要

The media filter drain (MFD), a stormwater water quality treatment best management practice, consists of media made up of aggregate, perlite, gypsum and dolomite in a trench located along roadway shoulders with gravel and vegetative pre-filtering facilities and optional underdrains. One of the many benefits of MFDs is the effective removal of dissolved zinc and copper from roadway runoff. However, the existing design includes use of an aggregate gradation that is no longer readily available (old design). A more readily available and economical aggregate gradation has a slightly lower percent of finer materials (new design). This project evaluates if the new design is as effective as the old design at enhanced dissolved zinc and copper treatment.