Virginia up to 10' (3 m) deep. <ref>Viriginia Deprtmant of Transport. (2010). VDOT BMP Design Manual of Practice. Retrieved March 15, 2018, from http://www.virginiadot.org/business/resources/LocDes/BMP_Design-Manual/Chapter_8_Infiltration_Trench.pdf</ref>
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*Virginia up to 10' (3 m) deep. <ref>Viriginia Deprtmant of Transport. (2010). VDOT BMP Design Manual of Practice. Retrieved March 15, 2018, from http://www.virginiadot.org/business/resources/LocDes/BMP_Design-Manual/Chapter_8_Infiltration_Trench.pdf</ref>
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Minnesota up to 12' (3.6 m) deep. <ref>Design criteria for Infiltration trench. (2016, September 21). Minnesota Stormwater Manual, . Retrieved 13:25, April 4, 2018 from https://stormwater.pca.state.mn.us/index.php?title=Design_criteria_for_Infiltration_trench&oldid=28702.</ref>
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*Minnesota up to 12' (3.6 m) deep. <ref>Design criteria for Infiltration trench. (2016, September 21). Minnesota Stormwater Manual, . Retrieved 13:25, April 4, 2018 from https://stormwater.pca.state.mn.us/index.php?title=Design_criteria_for_Infiltration_trench&oldid=28702.</ref>
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*"...not normally be deeper than 3 to 4 m in order to maximise the length of the flow path to the water table through the unsaturated zone." <ref>Design of soakaways (2015) www.tiipublications.ie/library/DN-DNG-03072-01.pdf</ref>