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| <p>[[Infiltration: Testing|Infiltration tests]] must be undertaken at the location, depth and with a head of water that replicates the proposed design. </p> | | <p>[[Infiltration: Testing|Infiltration tests]] must be undertaken at the location, depth and with a head of water that replicates the proposed design. </p> |
| <table> | | <table> |
− | <table class = "table-responsive table table-striped"> | + | <table class="table-responsive table table-striped"> |
− | <caption><strong>Suggested safety factors to be applied to measured percolation rate when designing infiltration facilities</strong></caption> | + | <caption><strong>Suggested safety factors to be applied to measured percolation rate when designing infiltration facilities</strong></caption> |
− | <tr class="success"> | + | <tr class="success"> |
− | <th rowspan="2">Catchment area</th><th colspan="3" class="text-center">Consequence of failure</th> | + | <th rowspan="2" class="text-center">Catchment area</th> |
− | <tr class="success"> | + | <th colspan="3" class="text-center">Consequence of failure</th> |
− | <th>No damage or inconvenience</th><th>Minor damage or inconvenience to external structures (e.g. ponding in parking lot)</th><th>Significant damage to buildings or infrastructure (e.g. flooding damage)</th></tr> | + | <tr class="success"> |
− | <tr><td> <100 m<sup>2</sup></td><td>1.5</td><td>2</td><td>10</td></tr> | + | <th class="text-center">No damage or inconvenience</th> |
− | <tr><td style="white-space: nowrap"> 100 - 1000 m<sup>2</sup><td>1.5</td><td>3</td><td>10</td></tr> | + | <th class="text-center">Minor damage or inconvenience to external structures (e.g. ponding in parking lot)</th> |
− | </table> | + | <th class="text-center">Significant damage to buildings or infrastructure (e.g. flooding damage)</th> |
| + | </tr> |
| + | <tr> |
| + | <td class="text-center"><100 m<sup>2</sup></td> |
| + | <td class="text-center">1.5</td> |
| + | <td class="text-center">2</td> |
| + | <td class="text-center">10</td> |
| + | </tr> |
| + | <tr> |
| + | <td style="white-space: nowrap" class="text-center"> 100 - 1000 m<sup>2</sup> |
| + | <td class="text-center">1.5</td> |
| + | <td class="text-center">3</td> |
| + | <td class="text-center">10</td> |
| + | </tr> |
| + | </table> |
| <h4>Groundwater</h4> | | <h4>Groundwater</h4> |
| <p> The bottom of the infiltration BMP must ≥ 1 m vertically separated from the seasonally high water table, and underlying bedrock. This reduces the risk of contaminating groundwater and helps to ensure reliable infiltration rates throughout the year. </p> | | <p> The bottom of the infiltration BMP must ≥ 1 m vertically separated from the seasonally high water table, and underlying bedrock. This reduces the risk of contaminating groundwater and helps to ensure reliable infiltration rates throughout the year. </p> |