Great website guys! Did a search on French Drain and believe I'm ready to start this project for in laws. Here is the issue: Backyard slopes towards house causing water to pool on lawn and back patio (pic). They had dogs which then get REALLY muddy as lawn is soggy at base. Backyard has existing surface drains (highligted in blue) which lawn doesn't grade towards so they do nothing. They do tie into gutter drain which goes to street. Ok so I need your opinion on whether a french drain is the best solution. Does there appear to be enough slope for water to travel down and collect in drain ? Can't get a bobcat in backyard to regrade so regrading grassy area towards surface drains is not an option. See my highlighted line where I want to install 4" french drain. It will wrap around and then connect to gutter drain which goes to street. I will then resod entire lawn (excluding gravel part of drain) and hope it works. Will be using perforated 2 hole 3" pipe with holes facing downward, fabric wrap, gravel,etc. Also I read a 1" slope for drain pipe for every 100 ft. That doesn't sound like enough ? Any other ideas on how to deal with soggy lawn is appreciated.