Erosion & Sediment Control
In addition to the model ordinance, this section includes several other materials that may be useful either in drafting an ordinance or as support material:
Introduction to Erosion and Sediment Control
By most accounts, the most dangerous period of development is the initial construction phase when land is cleared of vegetation and graded to create a proper surface for construction. The removal of natural vegetation and topsoil renders the exposed area particularly susceptible to erosion, causing transformation of existing drainage areas and disturbance of sensitive areas. Erosion control is the process of minimizing the amount of soil that runs off during the construction process, and sediment control is the process of retaining eroded soil on site, preventing damage to watercourses and infrastructure.
The model ordinance in this section borrows language from the model erosion and sediment control ordinance for Westchester County, New York, and also incorporates some additional features that may help prevent erosion and sedimentation and protect natural resources more fully. For example, the model ordinance emphasizes the use of techniques to limit clearing and grading, and requires that contractors be certified to maintain and inspect erosion and sediment control practices.
The model ordinance will need to be adapted in order to be broadly applied for several reasons. For example, some of the requirements may not be politically feasible or technically appropriate in all communities. In addition, the ordinance does not strongly correlate with the process by which building permits are granted, because the process may vary between communities.
The size of construction sites and specific design criteria within communities will dictate variations in any erosion and sediment control ordinance. However, there are a few elements that can help make an ordinance more effective, regardless of the more specific requirements:
Erosion and sediment control is widely accepted as a necessary practice, but there are certain caveats to making even the most well-crafted ordinance effective. First, communities need to have the staff and resources to enforce erosion and sediment control regulations, or the authority to inspect sites becomes useless. In addition, the technical manual referred to in the ordinance needs to provide useful guidance on selecting erosion and sediment control measures, and in particular should not include measures that are ineffective. Finally, education of contractors, engineers, and designers regarding the importance and effective use of erosion and sediment controls is imperative to implementing effective erosion and sediment control.