Basin selection
Candidate basins ranked by gallons per day per inch-mile (GPDIM).
Basin attribution model
Same storm, three candidate basins, ranked by GPDIM (structural density of failure), not raw volume.
Post-rehab verification (RDII reduction)0%
GPDIM ranking
GPDIM = attributed gallons / (sewer miles × avg diameter in × day). NAPOT compared against the 10 h/day capacity-certification limit. Select a row to inspect its hydrograph.
| # | Basin | RDII volume | Inflow share | GPDIM | NAPOT dry → storm | Signature |
|---|---|---|---|---|---|---|
| 1 | 16 mi · 9 in avg | 3.11 MG | 16% | 7,192 | 5.1 → 14.8 h | Saline infiltration · SLR exposure |
| 2 | 8 mi · 12 in avg · FOG restriction | 1.27 MG | 24% | 4,407 | 4.8 → 8.8 h | Infiltration · groundwater |
| 3 | 24 mi · 9 in avg | 1.90 MG | 27% | 2,931 | 5.3 → 11.2 h | Infiltration · groundwater |
Hydrograph decomposition · Candidate Basin A · Coastal tidal
Inflow spikes within the hour of rain; infiltration lags and persists for days. A dry-weather rise with no rain is the restriction (FOG) signature.
Salinity tracer
Four-electrode conductivity on the arriving flow. A rise on the infiltration tail means saline groundwater, which is a sea-level-rise exposure rather than a maintenance backlog.
- Peak conductivity
- 3,355 µS/cm
- Saline intrusion
- Detected
- Inflow gallons
- 492k gal
- Infiltration gallons
- 2.62 MG