Water Bound Macadam
The concept of water bound macadam road was suggested by John Macadam, who was a Scottish engineer.
The road whose wearing course consists of clean
crushed aggregates, mechanically interlocked by rolling and bound together with filler material and water laid on a well compacted base course, is called water bound macadam (W.B.M) road.
(What is Water Bound Macadam roads /what is WBM roads)
This is constructed as village road serves as a base for bituminous roads.
In most of the roads projects, in the first phase, W.B.M roads are constructed and when the funds are available, the surfacing is done with the premix carpet bituminous macadam or cement concrete. So a water-bound macadam road is
considered as the mother of all types of road construction.