Bituminous Geomembranes (BGMs) are a type of geomembrane that consists of a reinforcing geotextile to provide mechanical strength and elastomeric bitumen (often called asphalt in the US) to provide impermeability. Other components such as sand, a fiberglass veil and/or a polyester film can be incorporated into the layers of a BGM.[1] Bituminous geomembranes differ from bituminous waterproofing materials used in buildings in part due to their considerable roll width, which can exceed 5m, and their substantial thickness of up to 6.0mm.

These properties are designed for environmental protection, civil infrastructure and mining applications. [2]​.

The earliest estimated use of bitumen dates back 40,000 years to the Paleolithic era, and the historical use of bitumen as a waterproofing layer is extensive and well documented.[3] The modern development of bituminous geomembrane dates back to the first double-lining system conceived in 1974 by geosynthetics pioneer Jean-Pierre Giroud. This novel bituminous membrane was manufactured by in-situ spraying of hot bitumen onto a polyester geotextile previously installed on the supporting soil.[4] Shortly after this first installation, BGMs manufactured in industrial facilities with bitumen impregnation in the geotextile were developed, which allowed a high standard of quality control. BGMs applied by in-situ spraying were completely obsolete by 1988.[5]​.