How To Solve A Lawn Drainage ProblemHere is a lawn drainage challenge, some detailed photos of the problems, and some possible solutions. It was from someone who contacted me regarding drainage issues on his property, and I provided him with some possible solutions. Many of these issues are common. To correct your problem, you need to know what your land elevations are throughout the yard. Water flows only along land that is sloped, and your property needs to be re-graded properly. Here is an overview, however. It appears that the ground surrounding your patio is flat with nowhere for the water to go. You must pull the soil around your patio back for a minimum of 5 feet, and grade it at 1/4 of an inch per foot for a minimum 2% away from the patio. This means that the area five feet out (or more) will be lower than the patio area and water will drain in that direction. The grade of the sloped area draining towards this area (five feet out) will have to be adjusted. A swale would be created to correct the lawn drainage problem, and the swale should be a couple of feet wide and gentle, preferably not a ditch. Now this swale has to lead the water somewhere. The logical place seems to be around your house towards the storm drain out front. (Actually, both sides of your house, it appears.) All It looks like the high point of the swale should be around your patio, with separate swales leading the water around each side of your home, emptying into the storm drain on one side. I am not sure what is on the other side. Here is the catch. In order for the swales to rectify your lawn drainage problem, the elevation at your patio must be higher than the storm drain and But let's say this is very difficult to accomplish due to your existing grades. There is another option. That would be to install a perforated pipe wrapped in filter fabric and covered with decorative or crushed stone at the perimeter of your patio. Thus, all water leading there will enter into this pipe. Then...if your town will allow it, lead the pipe into the storm drain. (I am not sure what is happening on the other side.) If this is not allowed, you can install a drainage pit. This looks like a large drum, but has holes in it for water to percolate out. It is placed under ground. The pipes then lead into the drainage pit. These are rough concepts and really all your existing elevations need to be known for it to be designed accurately. This was very poor land planning and I am surprised whoever did it received approvals.
Return From Lawn Drainage to Landscape Grading
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There are a couple of ways to solve this problem. 
land along the rear and sides of your house has to be graded away from your house, and the swale should continue along the sides. 
there must be 1/4 of an inch per foot difference when calculated along the swale. So if the distance is 100 feet from the high point of the swale to the storm drain, for example, the difference in elevation must be around two feet...two feet higher at the patio than the storm drain. 
