I am looking for an engineer, probably a civil engineer, to advise me on the source of flooding on a home in Norwalk, CT, and to suggest a possible course of action to prevent any future localized flooding.

We had a couple feet of water inundating the home (on a slab) associated with localized flooding connected with Hurricane Ida recently. It appears that an apartment building to the rear of the house has hard-surfaced its entire lot, concentrating run-off which channeled across the rear edge of the home. The innundation was swift, and receded very fast, but left in its wake serioous damage. Exactly how did this water enter the house, if indeed the source is as I describe it, and what can be done–a flood wall, french drain, or something else–to prevent a recurrence?