If you've ever driven on State Route 52 north of San Diego, you've likely felt that roller coaster sensation along one infamous stretch.
It is the site of several serious crashes including one in April 2012 that killed two teenagers and severely injured several others.
The teenagers were riding in two separate vehicles and began racing each other on eastbound SR-52 at speeds of more than 100 miles per hour.
Anthony Foreman, 18, was killed in the crash.
His father Mark Foreman knows speed is mostly to blame for his son's death, but also wonders about why it happened where it did, in the spot along the highway known for those infamous “rollercoaster” dips.
“We have a witness that testified in court that he saw the rear end of the car lift off the ground at one point," Foreman said.
Many residents known the stretch of highway connecting I-15 and I-805 was built over a landfill.
Cathryn Bruce-Johnson with Caltrans says the agency has been fixing the road as the landfill beneath the highway sinks.
Foreman, a retired San Diego Police officer of 30 years, doesn't think the repairs are happening enough.
A report from the CHP of accidents in that area suggests a trend in crashes before and after those dips are fixed, he said.
"After the rehabilitation, the crashes are almost non-existent for awhile, and then they start picking up, and then the severity of them changes," Foreman told NBC 7.
Caltrans says the repairs are happening about every two years.
"Caltrans monitors SR52 as well as our other highways and freeways on a regular basis to determine what is needed,” Bruce-Johnson said. “We have the ability to take immediate action for any urgent items. Our priority is the safety of the motorists."
Santee high school student Jayli James Campbell, 16, also died in the April 2012 crash. Nineteen-year-old Michael Johnson pleaded guilty to racing and received three years probation. A second driver, who was 16 at the time of the crash, also entered a guilty plea and was sent to juvenile camp as punishment.