Front Fenders - Packed with Dirt

So, I did a bit of inspection on my 88 TC. Some previous owner put side skirts on the car, so I figured Id pull them off to see how much rust was behind. I found the fenders to be heavily rotted below the trim, likely due to the space behind the fender being packed with wet dirt! Where would this have come from?? Could this car have come from a flood?

Thanks.

Night crawlers are a good flood sign, it's probably 20 years of dirt. Bummer.

I agree with clifford. The PO probally didnt ever bother to wash out the wheel wells after sprinting down a dirt road or similiar.

Is it best to get new fenders or repair? I noticed that the fenders have VIN sticker on them...

If it were me, Id judge how the rest of the fender looked compared to the price/availability of a new/used fender. If the fender is otherwise perfectly straight, Id go for the repair.

Above the trim, they are both nearly perfect.