Our Yard

My husband has all these dreams about things we can do with our backyard. There is a spot in the back corner where the water drains weird. He got this idea about digging up the yard and putting screens or drainage things under it then replanting all the grass. I kind of nixed that one. Then he thought it would be cool to put in a running pond, bird bath, or something like that. I am hoping to only be here another year or two. So then he wanted to install a sprinkler system HIMSELF throughout our entire yard. He's good at fixing things, taking apart and figuring things out, etc. But he has absolutely NO experience with anything like complicated landscaping, running water pipes through stuff, or pond pumps. I don't want to get in over our heads!