Placing Geotextile Fabric and Drainage Pipe

What happens here

Behind the geogrid and drainage aggregate, a layer of geotextile filter fabric should be installed. This fabric acts as a permeable barrier, allowing water to pass through while preventing fine soil particles from migrating into the drainage aggregate and clogging it. The video shows this black fabric being rolled up and over the wall. Additionally, a perforated drainage pipe (often called a 'French drain') should be laid at the base of the drainage aggregate layer, behind the lowest course of blocks, and sloped towards an outlet to channel water away from the wall. This combination ensures efficient drainage. While the pipe isn't explicitly seen, the mention of 'drainage on the backside' implies its presence or necessity.

Goal: Prevent soil migration into drainage aggregate and effectively channel water away from the wall.