How can I help repair a local forest?

I moved to my house I live in today in 2005. There were woods down the street. Me and my friends used to play manhunt and other games down there when we were about 9-10 years old. But in 2008, many deadly storms came through my area and destroyed the forest. It used to have plenty of trees and flowers. but now its filled with dirty water and beer bottles. I want to know ALL of the possible ways I can help rebuild this forest!