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Line 552: i < 250 mm/h *Corrective action should first involve thoroughly sweeping and vacuuming the affected pavement area when dry in an attempt to remove sediment accumulated in the pavement joints or pore spaces. If vacuuming does not restore surface infiltration rate to an acceptable value (i.e., ≥ 250 mm/h) try manual or pressure washing means to remove surface crust and sediment from paver joints or pore spaces. *In extreme cases, removal of the affected portion of the surface course and bedding and reinstallation with materials that meet design specifications may be necessary.
→Water Treatment Performance Evaluations
When the objectives of BMP inspection include determining if the BMP is providing a minimum level of water treatment performance, design of the continuous monitoring program needs considerable thought. Table 8.10 describes some key considerations in program design.
When the objectives of BMP inspection include determining if the BMP is providing a minimum level of water treatment performance, design of the continuous monitoring program needs considerable thought. Table 8.10 describes some key considerations in program design.
{|class="wikitable" style="width: 1275px;"
|class="wikitable" style="width: 1275px;"
|+'''Key considerations in designing continuous monitoring programs for water treatment evaluation.'''
|+'''Key considerations in designing continuous monitoring programs for water treatment evaluation.'''
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|'''[[Bioretention: Internal water storage|BMP Water Storage Capacity]]'''
|'''[[Bioretention: Internal water storage|BMP Water Storage Capacity]]'''
|Many LID BMPs contain sub-drains that only flow during large storm events which will limit the number of events that produce water samples in a given year.
|Many LID BMPs contain sub-drains that only flow during large storm events which will limit the number of events that produce water samples in a given year.
|*Focus on BMPs that generate outflow during storm events of 25 mm depth or less. Budget for continuous monitoring periods of 6 months to 2 years to capture samples from enough storm events to produce meaningful results (at least 15) with site visits every 2 weeks to check on equipment and download and QA/QC check data.
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*Focus on BMPs that generate outflow during storm events of 25 mm depth or less.
*Budget for continuous monitoring periods of 6 months to 2 years to capture samples from enough storm events to produce meaningful results (at least 15) with site visits every 2 weeks to check on equipment and download and QA/QC check data.
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|'''[[Permeable pavement|Permeable pavements]]''' (pavement surface)
|'''[[Inlets|Inlet configuration]]'''
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Measuring and sampling inflow is often not feasible for BMPs that receive sheet flow or have multiple inlets.
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*When part of an Assumption inspection, issue a stop work order and contact the construction site supervisor, design professionals and property owner or project manager to determine follow-up tasks. Follow-up tasks involve scheduling FIT work to do further testing to determine the affected area and decide on corrective actions.
*Parallel measurement and sampling of outflow from a nearby, untreated drainage area is needed to evaluate water treatment performance of BMPs where inlet monitoring is not feasible.
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|'''[[Enhanced swales]] / [[Vegetated filter strips]] & [[Absorbent landscapes|Soil Amendment Areas]]''' (topsoil surface)
|'''Storm Event Size and Duration''
|i < 15 mm/h;
|i < 15 mm/h;
K<sub>S</sub> < 1.5 x 10-6 cm/s
K<sub>S</sub> < 1.5 x 10-6 cm/s