Line 11: |
Line 11: |
| Infiltration practices are not recommended: | | Infiltration practices are not recommended: |
| <ol> | | <ol> |
− | <li>Where the bedrock is within 1 m below the bottom of the proposed BMP.</li> | + | <li>Where the bedrock is within 1 m below the bottom of the proposed BMP,</li> |
− | <li>Where the seasonal high groundwater level comes within 1 m below the bottom of the proposed BMP. <br>Or in areas where increased infiltration will result in elevated groundwater levels, which can be demonstrated to damage critical utilities or private property. </li> | + | <li>Where the seasonal high groundwater level comes within 1 m below the bottom of the proposed BMP,<br>Or in areas where increased infiltration will result in elevated groundwater levels, which can be demonstrated to damage critical utilities or private property,</li> |
− | <li>Over swelling clays or unstable sub-soils</li> | + | <li>Over swelling clays or unstable sub-soils,</li> |
− | <li>Over contaminated soils or sites with high risk of contamination from onsite activities </li> | + | <li>Over contaminated soils or sites with high risk of contamination from onsite activities, </li> |
− | <li>In flood prone areas where the wastewater system is sensitive to groundwater conditions causing sewer backups, and where LID BMPs have been found to be ineffective. </li> | + | <li>In flood prone areas where the wastewater system is sensitive to groundwater conditions causing sewer backups, and where LID BMPs have been found to be ineffective,</li> |
− | <li>In areas where the ecology and natural hydrology are dependent upon surface water. </li> | + | <li>In areas where the ecology and natural hydrology are dependent upon surface water,</li> |
| <li>Where prohibitions and/or restrictions exist per approved Source Protection Plans (see MOECC guidance). | | <li>Where prohibitions and/or restrictions exist per approved Source Protection Plans (see MOECC guidance). |
| </ol> | | </ol> |
| + | <br><p> |
| + | Infiltration can still be optimized over 'tight' soils with infiltration rates ≤ 15 mm/hr: |
| + | <li>[[Partially infiltrating bioretention]]</li></p> |
| <br> | | <br> |
| <p>Without infiltration, many LID design alternatives exist which can still capture and retain stormwater: | | <p>Without infiltration, many LID design alternatives exist which can still capture and retain stormwater: |
| <ul> | | <ul> |
− | <li>[[Partially infiltrating bioretention]]</li>
| |
| <li>[[Bioretention planters]]</li> | | <li>[[Bioretention planters]]</li> |
| <li>[[Rainwater harvesting]]</li> | | <li>[[Rainwater harvesting]]</li> |