A multi-part reusable retaining wall and levee bag. The reusable levee bag includes a top bag section and a bottom bag portion removably affixed to the top bag portion. The combined top bag section and bottom bag portion define an interior space within which fillable material may be received to form a levee bag for use in flooding and other installations. The bottom bag section includes a receiving cell for receiving an end of another levee bag to connect multiple levee bags end to end to form a retaining wall with minimal gaps between levee bags. The bottom bag section is made of a biodegradable material while the top bag section is made of an alternative material. The reusable levee bag, once filled, may be disassembled and the top bag section reused while the bottom bag section may remain in place to biodegrade.