Many yards have low spots that fill with water. Sometimes a new patio or walk will actually create the problem: water doesn't soak through the new surface, running into the yard and puddling instead. Seepage trenches will solve the problem. Dig a trench at the low point of the problem area, line it with either flexible or rigid drainpipe, and channel the water away from the house and away from the neighbours. If you have nowhere to divert the water, run the pipe filled with stone. The water will collect there and percolate into the ground.