In this age of online one-upmanship, it’s not uncommon to see thrill seekers jumping from bridges and cliffs, recording the jump on video for their friends to admire and aspire to. However, this extreme sport is not only dangerous for the jumpers themselves, but can also be hazardous to people swimming or otherwise partaking in water activities under those structures. And finally, the jumping can even be harmful to the aquatic ecosystem – especially endangered species like the Austin Blind Salamander.

There are few things more dangerous than jumping off a bridge. According to a recent report published by the National Safety Council, the risk of death from bridge diving can range anywhere from 5% up to 100%. That’s because when people jump off bridges, they have a free fall of four to five seconds, which can reach speeds of 75 miles per hour. The impact of such a high speed dive causes the body to shatter and puncture vital organs, which can lead to deadly internal hemorrhaging. Then, after they hit the water, they can drown if they are not able to swim.

The report’s author, Dr. David M. Levy, also states that “most bridge-jumping fatalities occur in low-to medium-rise bridges because of the relatively short distance to the water and the difficulty of providing prehospital interventions beyond simple warming and fluid replacement.” However, even when the distance is shorter, the risk of injury or death is still very real. The reason for this is because of the physics of bridge jumping and the surface tension of water. When a person falls from a bridge, they can hit the water at an amazing speed – and because the water’s surface is less dense than the ground, the impact is much more severe.

While most bridge jumpers die from injuries sustained in the fall, some die from the subsequent drowning. Those who survive the impact and don’t drown may also suffer from traumatic brain injury, spinal cord injury, broken limbs and other injuries.

Despite the risks of jumping off bridges, it is a popular pastime for thrill seekers and can be found in cities across the country. In fact, some cities have even adopted ordinances banning bridge jumping or placing a heavy fine on those who do.

In a town like Cohasset, where a 16-year-old girl was hospitalized after hitting her head on a bridge support beam, local police want to begin enforcing the town’s bridge jumping ban. FOX 2’s SKY2 recently visited the area and witnessed multiple teens jumping off of the Hill Bridge into the water below.

While the bridge jumping may be fun for some, Hertig is not impressed. “There are snakes, there are monitor lizards and there’s been a few gators up here and it just isn’t a good idea,” Hertig says. He says he has called police on his property at least 16 times, and hopes they will help crack down on the activity.