Common use of Filter Blankets and Riprap Geotextile Clause in Contracts

Filter Blankets and Riprap Geotextile. Riprap shall be underlain by a sand and gravel filter (or geotextile fabric) to keep the fine materials in the natural or artificial channel from being washed through the voids in the riprap. Likewise, the filter material must be selected so that it is not washed through the voids in the riprap. For additional information and procedures for specifying filters of riprap and general guidance, refer to the ODOT Hydraulics Manual Chapter 8 (Channels) and 15 (Bank Protection).