Experts Warn Illinois and Indiana of Earthquake Liquefaction Risk and Aging Infrastructure

During the recent Vermillion County Mitigation Plan Meeting held on July 10, 2025, local officials discussed the pressing issue of earthquake preparedness, particularly given the county's proximity to the Wabash River and known fault lines. While Indiana has not experienced significant seismic activity, nearby Illinois has recorded small earthquakes, raising concerns about potential impacts on local infrastructure.

One of the key points highlighted was the phenomenon of soil liquefaction, which occurs when saturated soils behave like quicksand during an earthquake. Areas identified in pink on the maps presented during the meeting indicate high liquefaction potential, particularly along major streams. This poses a risk to critical infrastructure, such as water treatment plants, which may be vulnerable to foundation damage if an earthquake were to occur.

Officials noted that the average cost of damage from a significant earthquake is expected to rise, with predictions suggesting a strong shake could happen within the next 20 years. Many of the county's buildings, some over 150 years old, are not designed to withstand seismic activity, raising concerns about their structural integrity. Residential structures, in particular, are seen as a major contributor to debris in the event of an earthquake.

Participants were encouraged to assess the potential impact of earthquakes on their community, considering factors such as the probability of occurrence and the duration of shaking. The discussion underscored the importance of preparedness and awareness, as the aftermath of an earthquake can extend beyond the initial tremors, affecting daily life for an extended period.

As Vermillion County moves forward, the insights from this meeting will play a crucial role in shaping future mitigation strategies, ensuring that the community is better equipped to handle the risks associated with earthquakes and other natural hazards.