Some riprap is widely graded such that some believe it has a built in filter.
{"Image DocumentName": "Some riprap is widely graded such that some believe it has a built in filter.", "Image ImageDescription": "Quarry run riprap which has little processing at the quarry is an example. This riprap is the 10 thick riprap used on the upper bank of the Mississippi River over hundreds of miles. It has no separate filter..", "Image XResolution": "37", "Image YResolution": "37", "Image ResolutionUnit": "Pixels/Centimeter", "Image Software": "SlidePlayer", "Image YCbCrPositioning": "Centered"}