Replacing Culverts with Cut-offs On completion of harvesting, consider the removal of all culverts and replace them with broad cut-offs as these will not block as easily without regular maintenance. Cut-offs should direct stormwater to stable ground and be at least 50cm deeper than the road surface, 2m wide and slope downhill 15 to 20 degrees. 20˚ 2 m t Grass Fill Batters Any sort of ground cover on newly excavated or fill areas will help stabilise the soil and limit sediment run-off to waterways. Consider sowing down the fill batters with a bush burn or similar seed mix. 13 u c ROAD o -Water tableCut-o angle 50 cm