Responding to Ponding: The French Drain Solution

Jun. 20th, 2016 by W Scott McAdam Jr.

Heavy rainfall and extended rainy periods—as we have experienced recently—often results in ponding, the unwanted pooling of water.

Especially prevalent on properties in low-lying areas, ponding is most easily combatted by French drains. A French drain pit is a large hole at a property’s low point, filled with gravel to make it permeable, that hastens the flow of water through soil layers.

Limitations to the capacity of the French drain are based on soil composition, amount of rainfall, and the size of the area being collected from. Keep in mind, too, that water is capable of moving through and leaving soil in these four ways:

Downward Flow (Vertically) – Water moves vertically through soil profiles from layer to layer.

Horizontal Flow (Laterally) – Water moves laterally through the soil layer.

Evaporation – Water evaporates from the surface and into the atmosphere.

Absorption – Water is absorbed through plants’ root systems and is released as a gas through transpiration.

If the soil layers are fully saturated, it takes longer for water to drain because that saturation reduces its ability to move from areas of high potential (saturated) to low potential (unsaturated). 

P.S. This system was developed in the mid-1800s by an American whose last name happened to be French.

For more tips, visit www.mcadamlandscape.com or call McAdam Landscaping at 708-771-2299.

This first appeared as an "Ask the Plant Expert" advertorial in the June 15, 2016 edition of the Wednesday Journal of Oak Park and River Forest, Forest Park Review and Riverside-Brookfield Landmark.