I thank you from the bottom of my heart for your service!
I had severe erosion problems around my pond which is a similar size as yours. Here is a pic of what I did with rip rap. I put landscape fabric under it.
Bill D.
Edit: I ran the rip rap from low pool level to full pool level in my water table pond so I would not have to worry about my erosion control vegetation drowning out. On the side of my pond where erosion is much less of an issue, I did not use rip rap and am planting marginal vegetation.