What must be done to cut and fill slopes that are found to be eroding within one year of permanent stabilization?

Restabilizing eroding cut and fill slopes within a year of achieving permanent stabilization is crucial for several reasons. First, erosion increases sediment runoff into nearby water bodies, which can degrade water quality and harm aquatic habitats. By restabilizing these slopes, erosion processes can be mitigated, effectively preventing further degradation of the site and contributing to better stormwater management.

Restabilization involves implementing measures such as re-grading the slope, adding erosion control blankets, or re-vegetating the area with appropriate plant species. These practices enhance soil cohesion, slow down water runoff, and promote vegetation growth, which is essential for effective long-term stabilization. It also helps restore the initial effectiveness of the erosion control measures that were originally put in place.

The other approaches, such as leaving the slopes as they are, removing all vegetation, or increasing the slope angle, would likely exacerbate the erosion problem. Leaving the slopes unaffected fails to address the immediate issue of erosion. Removing vegetation, which plays a critical role in stabilizing the soil, would further destabilize the slope. Increasing the slope angle can make the slope more prone to sliding and collapsing, thereby increasing erosion risk. Therefore, restabilizing is the most effective and responsible action to take.