What must drivers do when three or more snowplows are operating in echelon formation?

When three or more snowplows are operating in echelon formation, it is essential for drivers to not pass or overtake the snowplows. This is because the snowplows are typically clearing the roadway and creating a safe path for vehicles by removing ice and snow. When they operate in an echelon formation, they cover a wider part of the roadway, and passing them could be dangerous due to limited visibility, the potential for encountering snow and ice on the road, or the sudden movements of the plows themselves.

Moreover, passing snowplows can lead to situations where drivers may misjudge the distance needed to safely navigate around them, leading to accidents. The proper course of action is to maintain a safe distance and allow the snowplows to clear the road without interference, ensuring both the safety of the drivers and the operators of the snowplows. This is particularly important in adverse weather conditions when traction and visibility are already compromised.