In most cases this is ground water. It is contaminated with dirt, chemicals and various other polluted items.
Contents that are salvageable can be taken outside and sprayed with a hose or pressure washer. They should also be wiped down with a disinfecting cleaner.
If soft goods such as pillows, sofas, mattresses, etc are wet, they should probably be thrown out. Carpets and pads should be thrown away. Drywall that is wet needs to be cut out and bagged. Wet baseboards need to be removed and discarded. If a sump pump is available use it to get the water out of the structure.
Hard toys can be cleaned and disinfected in a 10% bleach solution. Soft toys such as stuffed animals and dolls should be thrown out if they
Use paper masks and gloves if handling contaminated items and wear rubber boots if possible. Shower well afterwards.
Mold starts to grow in approximately 72 hours. It can be many, many days before restoration companies get to everyone, therefore, steps should be taken to minimize the damage.
Take pictures and video damage. Also, make lists of damaged items. This will be very helpful if the government approves help for flood losses.
Restoration companies will be asking for one half payment up front and one half when work is completed. This is just for emergency services. Those companies should be able to give a rough estimate at that time. Other local companies may ask for $1000 or more to respond.