m |
m |
||
Line 40: | Line 40: | ||
<tr> | <tr> | ||
<td>Silt loam, loam</td> | <td>Silt loam, loam</td> | ||
− | <td> | + | <td>'''OL''' – Organic silt or organic silt with sand or gravel or gravelly organic silt |
− | '''OL''' – Organic silt or organic silt with sand or gravel or gravelly organic silt | ||
</td> | </td> | ||
<td>B</td> | <td>B</td> | ||
Line 48: | Line 47: | ||
<tr> | <tr> | ||
<td>Sandy clay loam, silt</td> | <td>Sandy clay loam, silt</td> | ||
− | <td>'''GC''' – Clayey gravel or clayey gravel with sand | + | <td>'''ML''' – Silt |
+ | '''GC''' – Clayey gravel or clayey gravel with sand | ||
'''SC''' – Clayey sand or clayey sand with gravel | '''SC''' – Clayey sand or clayey sand with gravel | ||
</td> | </td> |
Design infiltration rate as a function of soil texture for bioretention in Minnesota
The values shown in this table are for uncompacted soils. This table can be used as a guide to determine if a soil is compacted. For information on alleviating compacted soils, link here. If a soil is compacted, reduce the soil infiltration rate by one level (e.g. for a compacted B(SM) use the infiltration rate for a B(MH) soil). Link to this table
Soil texture (USDA classification) | Corresponding Unified Soil Classification | Corresponding hydrologic soil Group (HSG) | Design Infiltration Rate (in/hr) |
---|---|---|---|
Gravel, sandy gravel, gravelly sand, and silty gravels | GW – Well-graded gravel or well-graded gravel with sand
GP – Poorly graded gravel or poorly graded gravel with sand |
A | Although a value of 1.63 inches per hour (4.14 centimeters per hour) may be used, it is Highly recommended that you conduct field infiltration tests or amend soils.b See Guidance for amending soils with rapid or high infiltration rates and Determining soil infiltration rates. |
Sand, loamy sand | GM – Silty gravel or silty gravel with sand SW – Well-graded sand or well-graded sand with gravel | A | 1.63 |
Sandy loam | SP – Poorly graded sand or poorly graded sand with gravel | A | 0.8 |
Silty sand | SM – Silty sand or silty sand with gravel | B | 0.45 |
Silt loam, loam | OL – Organic silt or organic silt with sand or gravel or gravelly organic silt | B | 0.3 |
Sandy clay loam, silt | ML – Silt
GC – Clayey gravel or clayey gravel with sand SC – Clayey sand or clayey sand with gravel |
C | 0.2 |
Clay, clay loam, silty clay loam, sandy clay, and silty clay | CL – Lean clay or lean clay with sand or gravel or gravelly lean clay
CH – Fat clay or fat clay with sand or gravel or gravelly fat clay OH – Organic clay or organic clay with sand or gravel or gravelly organic clay MH – Elastic silt or elastic silt with sand or gravel |
D | 0.06 |