With the recent heavy rains and localized flooding, many Northeast Georgia residents are dealing with drainage problems in their landscapes.

In many cases, residents have not experienced such problems in years in large part due to the lingering drought of 2007 and 2008. Unfortunately, landscape drainage problems are common in heavy clay soils like in our area.

Most landscape drainage problems are caused by compaction of the soil during construction projects or from poor planning when altering the original slope or grade of the landscape. The first step in correcting drainage problems is to understand where the water is coming from and why it is causing a problem.

Gutter downspouts are a major source of surface water flow. Downspouts are often located where it is convenient to install, not where it is best for site drainage. One of the best times to evaluate your gutter and drain system is during a heavy downpour.

As soon after a heavy storm as it is safe, check each downspout to determine how much water is flowing and where it is going.

Is it flowing back toward your house or under a crawl space? Does the downspout water form a stream in the landscape? Where does it end up? Are there places where water is discharged to a location from which it can not escape?

Another common source of drainage problems is improper grading of the landscape prior to landscape establishment. While it seems silly to state, it can never be stated enough that, "water runs downhill." It is surprising how often a landscape is graded so water is directed toward the house or to areas where water pools.

There are a few types of inexpensive levels available at hardware stores that can help you determine which way the grade is sloped. The term slope refers to the amount of rise or fall over a certain horizontal distance.

Ideally, the slope (or grade) next to a house or building should be a drop of at least 6 inches for every 10 feet. With special provisions, this amount cold be reduced to 3 inches for every 10 feet.

Aside from the drainage problems that can be observed on the surface, there could be a lot going on underground that is contributing to poor drainage conditions. Poor drainage can be caused by variety of natural and man-made means.

Some soils, particularly clay soils, drain slowly. With major landscape activity comes soil moving and compacting. The common practice of scraping the topsoil and saving for later often increases compaction, making the situation worse. There also can be problems when imported soil is layered over native soil. This is caused by variance in physical properties of the two soils.

One of the easiest ways to test your soil for drainage is to do what often called a perk test. Dig a hole approximately 8 to 12 inches deep, fill it full with water and let it drain completely. Wait a day or so and fill it again with water. Monitor the time it takes to drain back down. If it drains within one hour, you have excellent drainage. If it takes a few hours, you have adequate drainage. If it takes overnight to drain, you likely have a drainage problem.

Thanks to David Berle, University of Georgia landscape design specialist

Billy Skaggs is an agricultural agent and Hall County extension coordinator. Phone: 770-531-6988. Fax: 770-531-3994.