Which of the following is a primary impact of traffic incidents?

Traffic incidents often lead to significant congestion and delays on roadways. When a traffic incident occurs, whether it be an accident or a vehicle breakdown, it typically creates a bottleneck that disrupts the normal flow of traffic. This slowdown can lead to longer travel times for all vehicles on the road, increasing frustration for drivers and passengers alike.

Additionally, the presence of emergency responders at the scene of an incident can further exacerbate this congestion, as vehicles may have to navigate around blocked lanes or construction equipment. This phenomenon affects not only the immediate area of the incident but can also create ripple effects that impact traffic patterns over a wider region, resulting in delays that last long after the incident has been cleared.

Considering the other options, an increase in local wildlife does not directly correlate with traffic incidents, and improvements in public transportation are often unrelated. Similarly, a decrease in law enforcement activity is unlikely to be a direct result of traffic incidents, as law enforcement is typically more active in these situations to ensure safety and manage the incident. Hence, congestion and delay stand out clearly as the primary impact of traffic incidents.