between filter media and underlying aggregate is recommended instead. Geotextile socks should be installed on underdrain pipes with 360 degree perforations. Alternatively a strip of geotextile may be placed over the pipe to limit migration of fines from the overlying filter media into the pipe. Geotextile may be installed on the sides of the bioretention cell to maintain separation between backfill materials during construction. Geotextile used for weed control (i.e. landscape fabric) within the filter media bed or under mulch should be avoided. | between filter media and underlying aggregate is recommended instead. Geotextile socks should be installed on underdrain pipes with 360 degree perforations. Alternatively a strip of geotextile may be placed over the pipe to limit migration of fines from the overlying filter media into the pipe. Geotextile may be installed on the sides of the bioretention cell to maintain separation between backfill materials during construction. Geotextile used for weed control (i.e. landscape fabric) within the filter media bed or under mulch should be avoided. |