Tips for Digging a Dry Well

Purpose

• Dry wells act as drainage reservoirs in areas faced with onslaughts of excess water. Places that experience intense, infrequent rain are good candidates. Digging out an area and lining it with porous material creates a runoff area. When they are not put into place, standing surface water and flooding result. Other areas, such as swamp or marshland, do not benefit from dry wells. They are consistently saturated and a dry well does little to transform the overall landscape.

Location, Depth and Construction

• Dry wells are usually located near downspouts and gutters. They feature large amounts of water that are deposited in a small area. Even well-draining soils may find it difficult to absorb high quantities of water at once. Create a dry well by excavating a small pit to a depth of 1.5 to 3 feet. Line it with landscape fabric and fill it with coarse gravel. Locate dry wells 10 feet from building foundations and 75 feet from septic tanks and water wells. When storm water inundates the area, they absorb the runoff and slow its release into surrounding soil. They work most effectively in areas with permeable soil. Dry wells dug in areas with clay and compacted soils are less effective. Water will not drain into surrounding soil and the dry well will become a stagnant underground pool.

Drainage

• Working dry wells drain water completely within 48 hours after a storm or heavy rain. The structure's ability to absorb, retain and slowly release water prevents surrounding soil erosion and sediment dispersal. Monitor your dry well after a rain to ensure that it is releasing excess water into the surrounding soil. Also make sure the surrounding soil is able to absorb and circulate the stormwater. Dry wells are part of an overall drainage system and the entire system must function in order for it to work adequately. If it does not drain within 48 hours, check the area's soil for permeability. Dig a small hole approximately 1 foot deep. Fill it with water. If it does not drain within 24 hours then the area requires soil amendments and a more substantial drainage system than a dry well.

Considerations

• Before digging, consult with local ordinances. You may need to call your utility provider to ensure the area is safe. You also need to understand your land's grade and natural drainage structure. Avoid placing a drainage component, such as a dry well, in an area that can potentially damage or flood your neighbor's yard, house or land.