Grading (earthworks)
Grading in
improvements, or surface drainage. The earthworks created for such a purpose are often called the sub-grade or finished contouring (see diagram).Regrading
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)[3] or on quite a large scale (as in major reconfiguration of the terrain of a city, such as the Denny Regrade in Seattle).[2]
Regrading is typically performed to make land more level (flatter), in which case it is sometimes called levelling.[4]) Levelling can have the consequence of making other nearby slopes steeper, and potentially unstable or prone to erosion.
Transportation
In the case of gravel roads and earthworks for certain purposes, grading forms not just the base but the cover and surface of the finished construction, and is often called finished grade.[5]
Process
After the existing conditions of the limit of work has been surveyed,
Environmental design
In the
Purposes
Reasons for regrading include:
- Enabling construction on lands that were previously too varied and/or steeply sloped.[3]
- Enabling transportation along routes that were previously too varied and/or steep.[2]
- Changing drainage patterns and rerouting surface flow.[3]
- Improving the stability of terrain adjacent to developments.[7]
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.[3]
- Drainage problems (surface and/or subsurface flow) for areas not considered in the regrading plan.[8]
- 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)
- Regrading
- Slope (mathematical term)
- Subgrade
- Trench
References
- ^ "Grade.1.". def. 2. Whitney, William Dwight, and Benjamin E. Smith. The Century dictionary and cyclopedia vol.3. New York: Century Co., 1901. 2589. Print.
- ^ a b c Walt Crowley, Seattle Neighborhoods: Belltown-Denny Regrade -- Thumbnail History, HistoryLink.org essay #1123, May 10, 1999. Accessed online 16 October 2007.
- ^ a b c d Trees and Home Construction: Minimizing the impact of construction activity on trees, University of Ohio Extension Bulletin 870-99. Accessed online 16 October 2007.
- ^ "Montana, McLaren Tailings", p.35 in CERCLA Imminent Hazard Mining and Mineral Processing Facilities, Office of Solid Waste, U.S. Environmental Protection Agency, February 1997. Accessed online 16 October 2007.
- ISBN 978-1-118-41807-9.
- ISBN 9780132554343.
- ISBN 0-7277-1987-4. p. 63.
- ^ Barry Stone, Adjacent Property Regrading Creates Drainage Problem for Homeowner, doityourself.com. Accessed online 16 October 2007.
External links
- Matusik, John. "Grading and Earthworks" in The Land Development Handbook, 2004.
- Gravel Roads Construction and Maintenance Guide, Federal Highway Administration (FHWA) and the South Dakota Local Technical Assistance Program (SDLTAP), 2015.
- "How to Grade Gravel Roads" in Gravel Roads, Soil Stabilization, Soil-Sement® by Frank Elswick, 2017.
- Recommended Practices Manual: A Guideline for Maintenance and Service of Unpaved Roads, Choctawhatchee, Pea and Yellow Rivers Watershed Management Authority, 2000.