Drainages and culverts

hello;alot would depend on inspectors in your area,if there aren't any than you need to fill us in on the layout of the land,and do you want the minimal,make a wetland or just run-off?

hello gibson tembo,

actually you can construct or install drainage culvert beneath the road as long as it can resist the pressure above the structure but it is usually constructed/installed outside the road or outside the road shouldering or below the sidewalk inorder not to affect the traffic during maintenance/repair or replacement of the structure.

for reinforced concrete pipe culvert, the minimum backfill will be 600mm above the top of the pipe. if the depth of excavation is limited and the distance between the top of the pipe to the finish level of the road is less than the minimum, you can construct a reinforced concrete slab (cover above the pipe) in order to protect the pipe and lesser the pressure acting at the top of the pipe.