Drainage Solution: How to Re-Grade, Part 1
A good drainage solution to a drainage problem can almost always be found in altering the slope of your yard. This can usually be accomplished by redistributing the soil in your yard. You will, though, need the right kinds of soil, tools, materials, and instructions to be sure changes you make to the slope of your yard will solve your drainage problems.
Step 1 - Identify the Cause of Your Drainage Problem
The wrong slope in your yard may not be the source of your drainage problem. Before beginning to alter this slope, examine your yard for depressed areas where water may pool as it drains. Examine also your topsoil and subsoil to determine whether your soil is composed mostly of clay, sand, or loam. Water is more likely to drain faster through a sand or loam-based soil than one rich in clay. If you want to steer water to a specific location, dense, clay-based earth can help you do that. If you want water to drain through the ground faster, add some coarse, sandy dirt, which can filter water quickly through its larger particles.
Step 2 - Locate Utility or Sewer Lines
Before digging in your yard to remove soil in higher areas, check for electrical, telephone, water, sprinkler, and sewer lines that could be buried in these areas and that could be damaged by your digging. If you find shallow, buried lines, mark them with colored flags. Try to determine how deeply these lines are buried. If necessary, check with local utilities to have their technicians locate these lines for you.
Step 3 - Determine Your Drainage Slope Degree
Locate the high point and low point of your drainage slope. The high point should be the point nearest your home's foundation. The lowest point should be where your water drains into a gutter, storm sewer, or holding pond. Drive a stake into the ground at both these points. Run a string between these two points and tie one end to each of the stakes, pulling the string tight. Then, measure the degree of slope from the high point to the low point. This slope should be a drop of at least 12 inches for each 50 feet of linear distance. Be sure the string is tied at both stakes at the same distance up from the soil surface and that there are no high points in the soil surface between these two stakes. If there are any of these high points, remove the soil until the string is level.
Step 4 - Alter Your Slope
To alter your slope so that it creates better drainage, you can do one of three things: remove soil from the lower point of your slope or add soil to the high point, whichever is more practical and will give you better drainage. The third choice is to move existing soil from the low point to the high point. If you need to bring in soil to add to the high point, try to choose a soil that will be similar to the soil already in place.