CHAPTER III

DRAINAGE OF ROADS

The Necessity for Drainage--Importance of Design--Surface Drainage--Run-off--Ordinary Design of Ditches--Underground Water--Tile Drains--Lying Tile--Culverts--Length of Culvert-- Farm Entrance Culverts--Metal Pipe--Clay and Cement Concrete Pipe--Concrete Pipe--Endwalls for Culverts--Reinforced Concrete Box Culverts--Drop Inlet Culverts 29-41