It’s not always possible …
To restore a wetland to exactly how it was before.
Hole in the Donut is the case point.
Once upon a time it was pine flatwoods. That was before it was rock plowed for farming, and before those fields went fallow and filled in with Brazilian pepper, and before efforts were made to get pines to grow back.
The eventual solution was to scrape out the makeshift soil.
That turned it into a herbaceous marsh.