How would you solve rain runoff coming across your property?

Kinda hard to explain but the land our house is on is sloped from the left to the right. The other lots are all wooded, no houses at all other than mine on this side of the street. My yard doesn’t flood, but when it rains hard we get a few inches of runoff for a couple hours. Basically the back yard turns into a shallow river. There is a creek behind the house that would make a perfect place to steer the water into but it would be a massive job to do whatever needs to be done to divert it to that creek. I have a very low area in the back yard but I don’t want to fill this until I figure out how to divert the water because I’m afraid if the water can’t use this low spot as part of his path it will run closer to the house. I should also mention that my 12x24 shed is smack in the middle of the runoff path. It’s raised about 10” off the ground on concrete footers but I’d like it to not be bombarded with this little river. The area on the ‘upstream’ side of the shed is wooded and the area on the other side is lawn. I’m fully aware that this might be a job too big to bother with but just wondering if there’s an easy-ish solution.