A sinkhole is defined as a landform created by subsidence soil, sediment, or rock as underlying strata are dissolved by groundwater. A sinkhole may form either by the ground collapsing on itself to form a hole or by the ground settling to form a crater or indentation in the soil. Sinkholes develop underground; their appearance can be sudden and dramatic. Limestone-based soils in humid areas often contain caverns which occur at or near the water table. Roofs of the caverns can collapse, leaving a steep-sided pit that can be a few feet in diameter to several hundred feet. Sinkholes are common in various parts of Pennsylvania.
Sinkholes have caused damage to highways and roads. Motorists need to BE AWARE of their possible formation. Once they begin to form they can expand rapidly, especially during heavy rains.
Sinkhole formation cannot really be predicted, but there are things people can watch out for and precautions that can be taken.
Watch for signs of water disappearing from the surface (for example, the sudden loss of a steam or retention pond). Sinkholes may also be a result of a broken pipe or may cause pipes to break.
If a sinkhole occurs in an area of traffic, barricade it to prevent motorists or pedestrians from getting to close to it.
Remember that the size can continue to increase, so barricade it with ample room to spare. Check fields before undertaking machine-related activities, such as grass mowing.
Keep tractors and heavy machinery far enough away from the sinkhole, since the ground near the edge can easily give way. It is recommended that machinery stay at least as far from the edge as the hole is deep.
Sinkholes will be more prevalent during times of increased and rapid rainfall, such as with the type of rains occurring during a hurricane.
Call 9-1-1 and advise them of the sinkhole and of the hole is near utility lines or in a roadway. Restrict access to the hole.
Don’t get to close to or go down into the hole.
Do not allow unauthorized or inexperienced persons to investigate the sinkhole.
If the sinkhole is on your personal property, contact your insurance provider for additional instructions.
Keep the municipality in the loop. That helps local government keep a record of similar issues in the area and track potential causes and concerns.
OTHER SINKHOLE TIPS:
Rope off an area larger than the obvious depression or hole.
NEVER play in a suspicious hole or enter a sinkhole. It may be the top of a much deeper sinkhole.
Check for recent cracks in sidewalks, foundations and curbs for evidence of substantial movement.
Call in a respected excavation company to handle questionable sinkholes.
Filling holes and depressions with topsoil is like putting a Band-Aid on the problem, camouflaging the underlying problem.
Not all insurance policies cover sinkholes or sinkhole damage. Check with your insurance agent to determine your coverage and how to have sinkholes covered.