Thanks for the comments and links to other treads guys.

Part of my plan would be to include 2 other ponds for sediment control and forage raising areas. I also know that with the current pipe sizes that support the small ditch I can control the amount of water that flows through the ditch. I was mainly concerned with the shear volume washing away my fish in the larger spring snow melts and 4" rains.

I could build off to the sides of the ditch but this would require a lot more digging and dirt movement as a opposed to a small amount of dirt work and dam building.