I was hoping to find some info on exactly how this works? At first glance this wouldn’t appear to be effective as the oily water on the street, which is lower than the grassy strip, is not going to defy gravity and jump over the curb to get into the grassy area to be filtered. Obviously for this to be effective, there’s more to the picture than what you’ve told us; more than simply planting a grassy strip with the “right mix of plants.” Please, tell us more about how this works. Thanks.