A healthy and established pond should be fairly self sustaining, providing you help it along. My first recommendation is loose the geese. They can really crud up a pond very quickly and the around of fecal matter they release into the bond can be quite amazing and detrimental. Using bog/wetlands is a terrific way to "filter" but also to protect the pond. Natural or man-made riparian buffers are a terrific way to keep outside pollutants and nutrients out of the water. Basically, creating a small wetland/marginal area all around most of the pond will help protect and maintain it.
There is a lot of info floating around on the net about this. There are also tons of papers and articles of a scholarly type though you may have to be affiliated with a university to access many of them. If you find one that looks promising, let me know and I can try to get it for you. I would be interested in that also. Depending on where you live, your local university may have someone knowledgable in this or be able to point you to someone willing to help.
The relocation and re-creation of wetlands is becoming pretty popular for a variety of reasons, the largest being the need for building sites in populated areas. In the next town over for me, the only thing keeping out a second Super Walmart is toad and a turtle, both facing local extripation, that depend on the wetland Walmart wants to destroy. Go nature, go!
Anyway, a little google searching should give you tons of info and a call to your local college Enviromental Science department and maybe to the local branch of the state's department of ag or wildlife may be helpful. Keep in mind though that the state departments may find issues you are not aware of and give you lots of grief
Just do me one favor, stay away from plants that are not local to your area. We don't need any more invasive species and articulating to anyone you talk to that you understand that, you will probably get more help and interest in your project.
Sounds like a great project though . Photos?