| Line 22: | Line 22: | 
|  | *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> | 
|  | |} |  | |} | 
|  |  |  |  | 
| Line 44: | Line 61: | 
|  | *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>
 |  | 
| − | |}
 |  | 
|  | ---- |  | ---- |