My brick house was built in 1895 and is a narrow row house-duplex on a city street in the Mid-Atlantic region. When the sidewalks were replaced at some point the dip that runs from the rain spout to the street was replaced with a flat sidewalk. Now, instead of running away from the house the water pools there and has worn away some of the brick and created a hole that starts above the sidewalk and goes down below it. It's kind of a triangle shape at the corner of the house about 1 1/2 inches at the highest point and about 5 inches long. I haven't been in the house a year yet and didn't see the problem until it rained this past week; there were rocks stuck in it and leaves and snow around it when I was looking at the house. I am a complete novice but it seems to me like this is a huge problem. Can I patch it my self with some concrete? What needs to be done to fix this?