I am looking into making my pond larger in the near future. It is 1/4 of an acre and is fed by natural runoff. I was wondering what the best way, if any, to do this is. I was thinking about extending the dam to allow greater surface area to catch water. Any ideas?

Isaac, extending the dam is a good idea to enlarge. Also you might want to raise the spillway. In my opinion that is the best way to gain surface area as it increases the area and the depth.