• Where applicable, use practices such as turnouts or ditch plugs, to reduce the volume and velocity of ditch flow.
• All road drainage practices that divert ditch flow or road surface runoff, must direct such flow onto vegetated areas where it can be adequately dispersed - do not direct ditch flow or road runoff into streams, lakes or other waterbodies.
• Use cross-drain culverts on roads where there is a need to direct ditch flow from one side of a road to the other, underneath the road surface.
• Use cross-ditches on roads where there is a need to channel ditch or road surface drainage from one side of the road to the other, over the surface of the road.
• Base the size of the culvert or cross-ditch on the road ditch size, type and slope of the road and the expected volume of water to be handled during storm events.
• Use water turnouts to periodically turn ditch flow out and away from the road, and onto an adjacent vegetated area for dispersal of road runoff and sediment. Vegetated areas used for water turnouts must be adequate in size and have sufficient ground cover to assimilate discharges.
• Use broad base dips on permanent roads for dispersion of road surface drainage in the absence of road ditches - the use of a broad base dip provides exceptional drainage and virtually unlimited trafficability. This road drainage practice is best suited for new road construction and on especially critical road segments designed for all-weather traffic and heavy use.
• Use water bars for temporary access roads, firelines and skid trails, where a physical barrier is needed to disrupt and disperse runoff and sediment. Since water bars vary from 1 - 3 feet in height, they are generally not suitable for high speed or heavy traffic loads, but can be used to effectively close a road to vehicular traffic.
Road Maintenance
• All drainage structures should be periodically checked and maintained, especially following excessive rainfall events. If signs of sediment and/or turbid discharges are present, take immediate corrective actions for any problem.
• Ditches and culverts should be kept free of major obstructions and ditches should be allowed to revegetate as much as is practicable.
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