how drought tolerant is this meadow?

It only receives natural rainfall.

It would. You can do a lot over a septic field in my opinion. I wouldn't plant a Willow or any other large tree but beside that, I think anything else is fine. I'm a landscaper. I got tired of cutting so much lawn so I started growing plants on our property. I have 300 Boxwoods growing on top of my leaching field. My fields are pretty deep so I'm not at all concerned. Maybe if I had a shallow field or a raised field that they have in some parts of the country due to poor drainage, i'd be a little more cautious. Have you ever seen a tree blow over in a storm? At least around here, the root system looks like a pancake. 90% of roots are in the top foot of the soil.

This is just magical!!!
How do you go about starting a meadow? And what do you do before winter? If you mow it do the flowers grow back the next season?

Check out American Meadows online-they sell wildflower seeds and have all the info you need to start your own meadow:)