How to secure a retaining wall around a pond?
Hello! And thank you for reading my post.
First let me say, I have NO IDEA what I am doing. Secondly, I need to explain that I am doing this without spending any money, if possible.
I have wanted a garden pond for years ~ have been daydreaming about it, trying to decide where on my crazy property to locate it. Out of the blue, I got an offer I couldn't refuse ~ a neighbour with a big tractor would come over today and dig my pond for free. Given my landscape obstacles (there are many), my lack of knowledge, the power reading I did last night, and my imagination, I plotted a design for him to excavate on the East side of my house. My house is on the top of a fairly steep hill. I live in Nova Scotia (Canada), Zone 5.
The pond is dug into the side of the hill in the shape of a C (with one side a little longer than the other so that it is not symetrical. The back curve of the C, closest to the house, is dug so that the bottom of the pond is about 8 feet from the edge of the lawn. The hole graduates down to about 1 foot deep at the shallow "legs" of the C. Some of the dirt removed was placed around the "legs" of the C to create a bit of a levee affect. The remainder of the dirt was gradually sloped further down the natural slope of my lawn to marry up with the bottom of my hill.
The "plan" (I use that term loosely) is that the water level of the pond will be approximately 1 foot deep, with a "deeper end" extending to 3 feet deep at the back. So, about 5 feet high of a cliff will extend above the level of the water at the back of the pond, sloping down to a 1 foot "cliff" at the shallow end.
I would like to build a rock wall at the back of the pond. I have accumulated a fairly good pile of rocks from another neighbour's throw-aways (someone thought they were "bauxlite". I don't know. They break off in straight pieces if you crack them together). At the top of the stone wall I would like to plant things like Cotoniaster and Juniper.
a) How do I need to approach this cliff? My excavator dude suggested putting in a couple of pressure treated posts behind the rocks. What would the purpose of that be? And is there something else I could use? I thought that pressure treated wood adds bad chemicals to the ground?
b) The rocks will only be at the back of the C. As the cliff becomes lower and lower, is there something I can plant that will adhere to the sides of the earth so they will become root bound and create a natural retaining wall?
c) The purpose of the pond is to add beauty and joy to my life. I would like to create a waterfall in the rock retaining wall. I'd like to have a few gold fish swimming around in it. I'd like some water flowers/plants. I'd like to attract frogs, peepers, dragonflies, and whatever other critters would enjoy it as their home. Can you have all of these elements in the same pond? Am I absolutely required to have a filtration system with gold fish or is there a way to create a natural ecosystem that will take care of that on it's own (with my maintenance, of course)?
I'm including a couple of very short videos to help depict what I've tried to explain here.
I would be grateful for any advise you can offer. But please keep in mind my financial constraints.
Thank you most kindly!
PS ~ I was not able upload the videos ~ sorry.