Dover, Del. — Delaware homeowners face a generally low risk of sinkholes compared with many other parts of the country, but experts say subtle ground changes should still be taken seriously when they occur.
According to the U.S. Geological Survey, most of Delaware does not sit atop widespread limestone or other highly soluble rock formations commonly associated with sinkhole development. As a result, large-scale sinkhole activity is uncommon statewide.
Geologists caution, however, that low risk does not mean no risk. Isolated sinkholes can still occur in limited areas, particularly where localized pockets of soluble material exist or where groundwater conditions change due to heavy rainfall, construction activity, or aging drainage and sewer infrastructure.
Sinkholes typically develop gradually, even in low-risk regions. Experts emphasize that surface changes often serve as early indicators of underground erosion or soil movement long before a collapse occurs.
Homeowners may notice shallow depressions forming in yards, soil that feels soft or spongy underfoot, or unexpected areas of standing water. Cracks appearing in sidewalks, driveways, patios, or foundation walls can also reflect subtle ground movement rather than routine settling.
Other warning signs are easy to dismiss. Leaning fences, separating steps, tilting trees, or gaps opening between soil and concrete surfaces may sometimes point to localized ground instability rather than normal wear.
In Delaware, sinkhole-related concerns tend to be highly localized rather than widespread. Experts say risk can vary by neighborhood depending on soil composition, drainage patterns, land-use history, and infrastructure age.
The USGS advises homeowners not to fill depressions or cover affected areas if changes persist or worsen, as doing so can mask developing problems and delay proper evaluation by local officials or qualified professionals.
Experts stress that awareness — not alarm — remains the most effective response. Even in low-risk states, early attention to subtle ground changes can help reduce property damage and improve safety.
