Put in a dry well to intercept the runnoff then pipe it to the lowest spot in the yard. A trencher costs about a $100 bucks a half day and will make quick work of the digging the trench. Then go back and using a string line backfill the ditch to get the proper finish slope for the pipe. Once you have got the bottom of the ditch leveled out lay your pipe out, stick it together, tape your joints and kick it in the hole. I love watching geysers of storm water shooting out of a well designed drainage system during a hard rain.

This is not something a layman should be messing with. If you have concerns about the placement or functionality of the french drain, call that out to the contractor and suggest that a soils engineer be called in for a consultation. Or hire one yourself. The plus side is that once the back side of the drain has been planted, you should have far less problem with runoff and soil erosion. Without seeing the property, it's hard to be specific, but I would think this could very easily and attractively transitioned to a more naturalistic planting area, perhaps incorporating some native plantings, both trees and shrubs, as well as smaller ornamental plantings and groundcovers. French drains are rather common in my area due to the prevalence of sloped lots and issues very similar to those you describe and often define the boundary between lawns and mixed planting areas. Rather than the coarse gravel used for the bulk of the drain system, these are often "finished" with river rock, providing more of a dry stream effect and typically become an accent to the landscape rather than a detraction.

Abiotlegesse, As the OP who lived through this the last couple of years, my first thought to your post was RUN. For us, our problem only got worse until serious and expensive interventions happened. "Grading" and "scraping" our back and front side yard (done by the builder as a solution to my complaint) DIDN'T work. The developer did nothing to correct our problem - there was a lot of talk, but nothing was actually done by him. The builder tried the scraping and grading. But, by the time we got another heavy rain that proved it didn't work, our one year builder warranty was expired. However, I will say that French drains (multiple) did finally work for us. Late last summer, our neighbor to the west of us put in French drains that wrapped all the way around his back yard and emptied into his and my front yard, with our permission (he did this because his backyard was starting to flood so badly that it was coming into his house). Since a good deal of our water flows downhill from his house (and the houses west of him) his French drains helped the flooding on the west side of our backyard a bit. But, his French drains could't help the water that also was flowing from the houses behind us (south of us) into our backyard. Late this spring, my husband installed French drains along the middle and east side of our back fence line and down the east side of our backyard up to the front yard all the way to street. He also hooked into our western neighbor's French drain that was emptying into the west side of our front yard and he extended that out to empty into the street as well. Since then, we've had two very heavy (days long) stints of rain and I'm happy to say that our flooding problem is gone. We still have some minor puddling issues on the west side of our yard behind our shed (where we didn't install a French drain). But, we no longer have a river flowing through our backyard. And, even better, we no longer have the resulting lake sitting our backyard that then stays for several days to weeks before finally evaporating. I can't say whether or not they would be able to bring legal action against you if you backed out at this time. However, I will say that if you move forward with buying the house, before closing, you should try very hard to get the drainage issue documented in writing, detailing what the developer and/or builder has done so far to correct the issue, the fact that the issue is still not completely corrected, and that the developer and/or the builder will take further actions to ensure the issue is corrected to your satisfaction. Buying the house without some sort of written agreement about the specific existing issue will only make it that much harder for you to get them to correct later. For me, it was clear that we would need to take our developer to court if we wanted him to pay to correct our drainage issues. After a lot of debate and thought, we decided to spend our money on just fixing the problem ourselves versus legal fees that might get the developer to pay to fix our problem. We've certainly learned quite a bit about home buying the hard way with this experience (and it wasn't our first house buying experience). On the bright side, since we don't intend to retire here, we can use what we've learned to hopefully make the next buying experience much better.

You have settlement issues...this is usually covered under the 1st year warranty. Not sure about your new house warranty clause, but if this issue not covered under your new house warranty, hire a local landscaping company and have them fill in low spots and make sure you have proper grade pitched away from your house. This type of a settlement is common, and the builder is usually notified at the end of the 1st year... Just make sure you take care of this before the sidewalk starts to settle and that will cause a crack in it,