Design infiltration rate as a function of soil texture for bioretention in Minnesota
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, and silty gravels | GW – Well-graded gravel or well-graded gravel with sand
GP – Poorly graded gravel or poorly graded gravel with sand |
A | 1.63 |
| Sand, loamy sand, and sandy loam | GM – Silty gravel or silty gravel with sand
SW – Well-graded sand or well-graded sand with gravel 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 | ML – Silt
OL – Organic silt or organic silt with sand or gravel or gravelly organic silt |
B | 0.3 |
| Sandy clay loam | 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 |