Engineering:Regrading

The Denny Regrade in process, Seattle, Washington (1900s).

Regrading for a subdivision in the Santa Monica Mountains, Los Angeles, California (1970s).

Regrading is the process of grading for raising and/or lowering the levels of land. Such a project can also be referred to as a regrade.

Regrading may be done on a small scale (as in preparation of a house site) or on quite a large scale (as in major reconfiguration of the terrain of a city, such as the Denny Regrade in Seattle).

Regrading is typically performed to make land more level (flatter), in which case it is sometimes called levelling.) Levelling can have the consequence of making other nearby slopes steeper, and potentially unstable or prone to erosion.

Purposes

Reasons for regrading include:

• Enabling construction on lands that were previously too varied and/or steeply sloped.
• Enabling transportation along routes that were previously too varied and/or steep.
• Changing drainage patterns and rerouting surface flow.
• Improving the stability of terrain adjacent to developments.

Consequences

Potential problems and consequences from regrading include:

• Soil and/or slope instability
• Terrain prone to erosion
• Ecological impacts, habitat destruction, terrestrial and/or aquatic biological losses.
• Drainage problems (surface and/or subsurface flow) for areas not considered in the regrading plan.
• Loss of aesthetic natural landscape topography and/or historical cultural landscapes.

See also

• Cut (earthmoving)
• Cut-and-cover
• Cut and fill
• Fill dirt
• Grade (slope) (civil engineering and geographical term)
• Grading (engineering)
• Slope (mathematical term)
• Subgrade
• Trench