Slope Physics Simulation
HYDROPHOBIC BARRIER ACTIVE
Rain
Hydrophobic Soil
Runoff Surge
INFILTRATION RATE
4.2 mm/hr
OVERLAND FLOW VELOCITY
2.18 m/s
SEDIMENT DETACHMENT
142 t/ha/yr
WATER REPELLENCY (WDPT)
3,450 s (Severe)
🔬 Soil Hydrophobicity Mechanics (Mediterranean Post-Fire)
High-severity Mediterranean wildfire heat (>175°C to 280°C) vaporizes soil organic plant matter (leaves, resins, pinene). These vaporized hydrophobic compounds migrate downward into the cooler soil column (2–6 cm depth), condensing into a waxy, water-repellent layer coating mineral soil grains.
During intense convection rainfall (e.g. 65 mm/hr Gothenburg/Valencia autumn storms), water droplets cannot break the high capillary contact angle. Instead of absorbing into the earth, rain converts directly to swift sheet wash and flash floods.
USGS Hydrograph & Peak Discharge
Catchment: 150 ha
PEAK DISCHARGE (Q_peak)
22.8 m³/s
+480% vs unburned
RUNOFF COEFFICIENT (C)
0.84
Unburned benchmark: 0.15
TIME TO PEAK (Tc)
14.2 min
Rapid surge window
DEBRIS FLOW HAZARD
82% (High Risk)
Trigger Threshold Exceeded
Catchment Parameter Workbench
Precipitation Rate
65 mm/hr
Catchment Slope Angle
32° (Steep Ridge)
Waxy Hydrophobic Depth
4.5 cm