Earthworks are engineering works created through the moving or processing of parts of the earth’s surface involving quantities of soil or unformed rock. The earth may be moved to another location and formed into a desired shape for a purpose. Much of earthworks involve machine excavation and cut & fill.

Cut section

Cut slopes are rarely created greater than a slope of two to one (horizontal to vertical dimensions).[2] Cut sections of roadway or rail are characterized by the roadway being lower in elevation than the surrounding terrain. From an operational standpoint there are unique environmental effects associated with cut sections of roadway. For example, air pollutants can concentrate in the ”valleys”created by the cut section. Conversely, noise pollution is mitigated by cut sections since an effective blockage of line of sight sound propagation is created by the depressed roadway design.

Fill section

Fill sections manifest as elevated sections of a roadway or trackbed. Environmental effects of fill sections are typically favorable with respect to air pollution dispersal, but in the matter of sound propagation, exposure of nearby residents is generally increased, since sound walls and other forms of sound path blockage are less effective in this geometry.

There are a variety of reasons for creating fills, among them reduction of grade along a route or elevation of the route above water, swampy ground, or areas where snow drifts frequently collect. Fills can also be used to cover tree stumps, rocks, or unstable soil, in which case material with a higher bearing capacity is placed on top of the obstacle in order to carry the weight of the roadway or railway and reduce differential settlement.