Water pooling causes drainage problems and can occur for several reasons. Water can accumulate in flat low-lying areas or in depressions. Pooling may also occur because soil is highly hydric and retains water rather than allowing it to drain properly. If pooling water begins draining toward the home it can become an even greater concern. Pooling water can be a significant obstacle in landscaping, but not an insurmountable one.
If water spilling out of area of pooling is directed toward the home or other undesirable area, a swale can be used to redirect the flow of water. The swale can also help to minimize pooling. A swale is simply a shallow trough cut into the landscape. Swales must be constructed deep enough to handle high volumes of water flow. A good swale is about 3 feet across and the top and narrows down to a depth of at least 6 inches. However, you may wish to make your swale deeper. In order for the swale to eliminate pooling it must start at an elevation equal to the lowest depth of the area of pooling and continue outward at a stead downward slope. If you are attempting to direct water away from its natural direction of flow, toward a house or other undesirable location, you may find yourself fighting the slope of the property and will need to trench a swale significantly deeper than just 6 inches.
If the lay of the property does not permit for a swale, or if a swale is not practical (as in the case mentioned above), then installing drain pipes may be more effective. With drain pipes, water is allowed to enter the underground pipe systems through grated inlets. The inlets should be set at the absolute lowest point in any areas of pooling to allow complete drainage into the subterranean pipe system. The pipes, themselves, should follow a consistent downward slope in the direction you wish the water to flow. The drain pipes should empty out into a nearby creek, water way, wooded area or street.
In instances where water collects around the foundation of the home, it is often better to use 4 inch (or larger) perforated drain pipes. The area around the foundation should be excavated and the pipes should then be buried in gravel extending out at least one foot from the foundation and one foot below the surface. The gravel will allow water to drain quickly and enter into the drain pipes without collecting around the foundation. The drain pipes can then be routed into an existing drainage system or directed out to the street.
Enlisting the Aid of a Pro
In many cases the scope of a drainage project is beyond the means of the average homeowner. It is best to remember that a failed attempt can be more costly than just hiring a professional from the onset. If you are unsure of the drainage needs of your landscape and property, or if you are unsure of your ability to tackle the project, then you are probably better off calling in a professional like Ground Source!