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| *Single ring infiltrometer | | *Single ring infiltrometer |
| *Soil textural classification | | *Soil textural classification |
| + | |} |
| + | ==Safety correction== |
| + | The measured or calculated infiltration rate must be divided by a value 2 or 3 before use in design<ref>Design criteria for infiltration. (2018, February 14). Minnesota Stormwater Manual, . Retrieved 00:16, March 14, 2018 from https://stormwater.pca.state.mn.us/index.php?title=Design_criteria_for_infiltration&oldid=35583.</ref> |
| + | {| class="wikitable" |
| + | |+ Selecting a safety factor |
| + | |- |
| + | ! 2 |
| + | ! 3 |
| + | |- |
| + | |Catchment < 100 m² |
| + | |Catchment > 100 m²<ref>Ballard, B. W., Wilson, S., Udale-Clarke, H., Illman, S., Scott, T., Ashley, R., & Kellagher, R. (2015). The SuDS Manual. London.</ref> |
| + | |- |
| + | |Permeameter or percolation test on site |
| + | |Double ring infiltrometer test on site, or grain size analysis used <ref>San Francisco Public Utilities Commission. (2017). Determination of Design Infiltration Rates for the Sizing of Infiltration‐based Green Infrastructure Facilities. Retrieved from http://sfwater.org/modules/showdocument.aspx?documentid=9681</ref> |
| + | |- |
| + | |Loamy or sandy soil |
| + | |Clayey soil<ref>CRC for Water Sensitive Cities. (2015). Adoption Guidelines for Stormwater Biofiltration Systems: Appendix C - Guidelines for filter media in stormwater biofiltration systems.</ref> |
| |} | | |} |
| | | |
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| *Existing data from borehole, well and geophysical testing; and | | *Existing data from borehole, well and geophysical testing; and |
| *Proposed location of development features (buildings, roads, utilities, etc.). | | *Proposed location of development features (buildings, roads, utilities, etc.). |
| + | ===Sampling=== |
| + | |
| + | *The recommendations above are guidelines. Additional tests should be conducted if local conditions indicate significant variability in soil types, geology, water table levels, depth and type of bedrock, topography, etc. |
| + | *Similarly, uniform site conditions may indicate that fewer test pits are required. Excessive testing and disturbance of the site prior to construction is not recommended. <ref>Christopher B. Burke Engineering LLC. (2009). Soil Infiltration Testing Protocol SOIL INFILTRATION TESTING PROTOCOL Purpose of this Protocol Who Should Conduct Testing. Retrieved from https://www.in.gov/ocra/files/Appendix F - Soil Infiltration Testing Protocol.pdf</re> |
| | | |
− | ==Safety correction==
| |
− | The measured or calculated infiltration rate must be divided by a value 2 or 3 before use in design<ref>Design criteria for infiltration. (2018, February 14). Minnesota Stormwater Manual, . Retrieved 00:16, March 14, 2018 from https://stormwater.pca.state.mn.us/index.php?title=Design_criteria_for_infiltration&oldid=35583.</ref>
| |
− | {| class="wikitable"
| |
− | |+ Selecting a safety factor
| |
− | |-
| |
− | ! 2
| |
− | ! 3
| |
− | |-
| |
− | |Catchment < 100 m²
| |
− | |Catchment > 100 m²<ref>Ballard, B. W., Wilson, S., Udale-Clarke, H., Illman, S., Scott, T., Ashley, R., & Kellagher, R. (2015). The SuDS Manual. London.</ref>
| |
− | |-
| |
− | |Permeameter or percolation test on site
| |
− | |Double ring infiltrometer test on site, or grain size analysis used <ref>San Francisco Public Utilities Commission. (2017). Determination of Design Infiltration Rates for the Sizing of Infiltration‐based Green Infrastructure Facilities. Retrieved from http://sfwater.org/modules/showdocument.aspx?documentid=9681</ref>
| |
− | |-
| |
− | |Loamy or sandy soil
| |
− | |Clayey soil<ref>CRC for Water Sensitive Cities. (2015). Adoption Guidelines for Stormwater Biofiltration Systems: Appendix C - Guidelines for filter media in stormwater biofiltration systems.</ref>
| |
− | |}
| |
| ---- | | ---- |