Is the bottom picture where the damm eroded? Any pond can be expanded just think it over and plan it out if your rent a machine and dig some test holes for soil sampling and perk.
JUst proceed with caution you are in a valley with alot of ledge and I would see if the existing pond is a natural or man made bottom seal Good Luck


Scott Trava
Catskill Pond
http://catskillpond.com
[email protected]
Returning Catskill Waters To A Simpler Time
EST. 1923