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==Excavation and rough grade==
 
==Excavation and rough grade==
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Excavation to the specified depths in the drawings is critical to the LID feature’s future performance. It also requires heavy machinery which, if used incorrectly, can compact soils and lower their native infiltration rates. <br/>
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Excavation to the specified depths in the drawings is critical to the LID feature’s future performance. It also requires heavy machinery which, if used incorrectly, can compact soils and lower their native infiltration rates. Over compaction of native soil underlying LID practices that infiltrate stormwater has been shown to negatively affect their drainage function.  To limit soil compaction the location of infiltration practices should be well-marked and surrounded by perimeter controls to protect the area from heavy equipment and vehicle traffic during site construction.  Excavation should be performed by a low ground pressure tracked excavator that is kept outside the footprint of the infiltration facility and not when soils are saturated.  If over-compaction does occur, it can be alleviated by soil fracturing (i.e., scooping and re-depositing native soils at the base of the practice), tilling with a subsoiler or rototiller, or raking using a toothed excavator bucket.
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[[File:Excavation outside in 2.jpg|400px|thumb|right|Excavating from impervious surfaces adjacent to the LID practice minimizes compaction. (Photo Source: CVC, 2018)]]
 
[[File:Excavation outside in 2.jpg|400px|thumb|right|Excavating from impervious surfaces adjacent to the LID practice minimizes compaction. (Photo Source: CVC, 2018)]]
 
'''Construction steps'''
 
'''Construction steps'''

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