Flood cleanup
Water that came in from outside brings whatever it crossed on the way — soil, fuel, fertiliser, whatever was in the street and in the sewer. That changes what can be dried and kept, and what has to go.
The category decides everything else
The restoration industry classifies water by contamination. Clean water from a supply line is one thing. Water that has passed through a sewer, a river or a street is another, and porous materials it has touched — carpet, padding, insulation, particleboard — are generally not salvageable regardless of how well they dry.
This is the single most common point of surprise for homeowners: the flooring is not being removed because it is wet, it is being removed because of what the water was carrying.
Extraction, then demolition, then drying
Standing water comes out first, because nothing else can start while it is there. Then the unsalvageable material is removed, which also opens the assemblies so air can reach what stays. Only then does drying begin, with air movers and dehumidifiers running for days.
The drying is the part that takes time and the part homeowners find hardest to wait through, because by then the room looks empty and finished.
Why New Jersey basements see this repeatedly
The remnants of Hurricane Ida in September 2021 put water into homes across Somerset, Union and Middlesex counties that had never taken water before. Along the Rahway, the Raritan and the Elizabeth River, and in the lower sections of Woodbridge and Perth Amboy, it was not the first time and will not be the last. In the older cities, combined sewers add a second route in that has nothing to do with how close the house is to a river.