{{Short description|In civil engineering, creating a profile}} {{About|earthwork|lumber grading|Lumber#Grades and standards|the photography term|Color grading}} upright=2.36|thumb|right|Section through railway track and foundation showing the sub-grade
'''Grading''' in civil engineering and landscape architectural construction is the work of ensuring a level base, or one with a specified slope,<ref>"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.</ref> for a construction work such as a foundation, the base course for a road or a railway, or landscape and garden improvements, or surface drainage. The earthworks created for such a purpose are often called the '''sub-grade''' or '''finished contouring''' (see diagram).
== Regrading == [[File:Denny Regrade-1.jpg|thumb|left|The Denny Regrade in process, Seattle, Washington (1900s).<ref name=Denny-Crowley>Walt Crowley, [http://www.historylink.org/essays/output.cfm?file_id=1123 Seattle Neighborhoods: Belltown-Denny Regrade -- Thumbnail History], HistoryLink.org essay #1123, May 10, 1999. Accessed online 16 October 2007.</ref>]] [[File:TERRACED HILLSIDE NEAR MULHOLLAND DRIVE IN THE SANTA MONICA MOUNTAINS ON THE WESTERN EDGE OF LOS ANGELES PORTENDS... - NARA - 557548.jpg|thumb|upright=1.15|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)<ref name=Ohio-tree>[http://ohioline.osu.edu/b870/b870_6.html Trees and Home Construction: Minimizing the impact of construction activity on trees], University of Ohio Extension Bulletin 870-99. Accessed online 16 October 2007.</ref> or on quite a large scale (as in major reconfiguration of the terrain of a city, such as the Denny Regrade in Seattle).<ref name=Denny-Crowley />
Regrading is typically performed to make land more level (flatter), in which case it is sometimes called '''levelling'''.<ref>"Montana, McLaren Tailings", p.35 in [https://web.archive.org/web/20040522022542/http://www.epa.gov/epaoswer/hazwaste/ldr/mine/cercla.pdf CERCLA Imminent Hazard Mining and Mineral Processing Facilities], Office of Solid Waste, U.S. Environmental Protection Agency, February 1997. Accessed online 16 October 2007.</ref>) Levelling can have the consequence of making other nearby slopes steeper, and potentially unstable or prone to erosion. {{clear left}}
==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'''.<ref>{{Cite book |last=Workshop |first=Design |url=https://books.google.com/books?id=yIWbCgAAQBAJ&dq=Grading+in+civil+engineering+and+landscape+architectural+construction+i&pg=PA321 |title=Landscape Architecture Documentation Standards: Principles, Guidelines, and Best Practices |date=2015-12-02 |publisher=John Wiley & Sons |isbn=978-1-118-41807-9 |language=en}}</ref>
==Process== [[File:Motoniveladora 01.jpg|thumb|right|Modern road grader]] After the existing conditions of the limit of work has been surveyed, surveyors will set stakes in places that are to be regraded. These stakes have marks on them that either give a finished grade to the design of the project, or have CUT/FILL marks which specify how much dirt is to be added or subtracted. All grade marks are relative to site benchmarks that have been established.<ref>{{Cite book |last=Ghilani |first=Charles |title=Elementary Surveying: An Introduction To Geomatics |publisher=Pearson |year=2011 |isbn=9780132554343 |edition=13th |pages=698–699}}</ref> The regrading work is then often done using heavy machinery like bulldozers and excavators to roughly prepare an area, then a grader is used for a finer finish.
==Environmental design== In the environmental design professions, grading and regrading are a specifications and construction component in landscape design, landscape architecture, and architecture projects. It is used for buildings or outdoor amenities regarding foundations and footings, slope terracing and stabilizing, aesthetic contouring, and directing surface runoff drainage of stormwater and domestic/irrigation runoff flows.
==Purposes== Reasons for regrading include: * Enabling construction on lands that were previously too varied and/or steeply sloped.<ref name=Ohio-tree /> * Enabling transportation along routes that were previously too varied and/or steep.<ref name=Denny-Crowley /> * Changing drainage patterns and rerouting surface flow.<ref name=Ohio-tree /> * Improving the stability of terrain adjacent to developments.<ref>Malcolm Puller, ''Deep Excavations: A Practical Manual'', Thomas Telford (1996). {{ISBN|0-7277-1987-4}}. p. 63.</ref>
==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.<ref name=Ohio-tree /> * Drainage problems (surface and/or subsurface flow) for areas not considered in the regrading plan.<ref>Barry Stone, [http://www.doityourself.com/stry/propertyregrading Adjacent Property Regrading Creates Drainage Problem for Homeowner]{{Dead link|date=March 2026 |bot=InternetArchiveBot }}, doityourself.com. Accessed online 16 October 2007.</ref> * Loss of aesthetic natural landscape topography and/or historical cultural landscapes.
== See also == {{div col|colwidth=27em}} * Cut (earthmoving) * Cut-and-cover * Cut and fill * Fill dirt * Grade (slope) (civil engineering and geographical term) * Land development * Slope (mathematical term) * Subgrade * Trench {{Div col end}}
==References== {{Reflist|22em}}
== External links == {{Commons category|Grading}} {{Commons category|Regrading}} * Matusik, John. [https://web.archive.org/web/20181024112605/http://my.fit.edu/~locurcio/14-Civil%20%26%20Const%20handbooks/Land%20Development/Ch24-Earthwork.pdf "Grading and Earthworks"] in ''The Land Development Handbook'', 2004. * [http://www2.ku.edu/~kutc/pdffiles/FHWAGravelRoadsGuide2015.pdf ''Gravel Roads Construction and Maintenance Guide''] {{Webarchive|url=https://web.archive.org/web/20181215223557/http://www2.ku.edu/~kutc/pdffiles/FHWAGravelRoadsGuide2015.pdf |date=2018-12-15 }}, Federal Highway Administration (FHWA) and the South Dakota Local Technical Assistance Program (SDLTAP), 2015. * [http://blog.midwestind.com/how-to-grade-gravel-roads/ "How to Grade Gravel Roads"] in ''Gravel Roads, Soil Stabilization, Soil-Sement®'' by Frank Elswick, 2017. * [https://www.epa.gov/sites/default/files/2015-10/documents/2003_07_02_nps_unpavedroads_unpavedtxtonly.pdf ''Recommended Practices Manual: A Guideline for Maintenance and Service of Unpaved Roads''], Choctawhatchee, Pea and Yellow Rivers Watershed Management Authority, 2000.
{{Geotechnical engineering}} {{Authority control}}
Category:Construction Category:Artificial landforms Category:Gardening aids Category:Landscape architecture Category:Road construction