The in situ/full-scale performance of recycled (or reclaimed) concrete aggregate (RCA) as a pipe bedding and backfill material of a French drainage system is investigated in this paper. The project’s purpose is to evaluate the effectiveness of full-scale French drainages in the field for long-term exfiltration drainage. Four French drains were built with a distinct material condition, namely, limestone, RCA “as is,” RCA with 2 % more particles, and RCA with 4 % more particles. The exfiltration subdrainage performance of each RCA French drainage system was evaluated using laboratory and field experiments. For a period of 12 months in the field, the flow rate and discharge rate of those drainage systems were tracked and quantified to establish the average permittivity of each trench. The laboratory testing program included exfiltration testing of nonwoven fabric (geotextiles) and RCA material characterization. After the 12-month period, geotextiles from each of the RCA French drainage systems were taken out and the average permittivity was measured. The findings indicate that the permeability of the surrounding soils and the existing groundwater table are the two most important elements impacting the subdrainage performance (exfiltration) of French drain systems. Notably, the type of aggregate (e.g., RCA or limestone) has a minimal impact on their exfiltration effectiveness. In conclusion, using RCA as a subdrainage material does not cause a substantial reduction in drainage system exfiltration performance compared with natural aggregate (limestone).