New research from Carfax suggests that drivers may be behind the wheel of more than 325,000 previously flooded vehicles. That number is a 20% increase from 2016 and a stark reminder to consumers to do their due diligence when used car shopping.

Vehicles reported as flood damaged by a state's Department of Motor Vehicles, insurance companies and more have washed up in every state, and these ten states have the most:

"I bought a car last year and the seller never told us anything about it being a flood car," said Charlene Geiger from Pennsylvania. "When we got home and ran a Carfax, there it was – a flood car from Hurricane Sandy. It showed that the seller bought it as a salvage car and the title was washed when he brought to Pennsylvania. We lost $16,000 over all of it."

In addition to the current total, several hundred thousand more flooded cars may emerge from hurricanes Harvey and Irma. Historically, about half the vehicles damaged by floods end up back on the market. Flooded cars rot from the inside out as water corrodes the mechanical parts, shorts the electrical system and compromises safety features like airbags and anti-lock brakes. Health concerns are an added problem, as mold and bacteria permeate the soft parts of the car.

"Our data shows there's still much work to be done in helping consumers avoid buying flood damaged cars," said Dick Raines, president of Carfax. "They can, and do, show up all over the country, whether it be a few miles or hundreds of miles from where the flooding occurred. With two devastating storms already this year, it's vital for used car buyers everywhere to protect themselves from flooded cars that may wind up for sale. Start with a thorough test drive, a vehicle history report and a mechanic's inspection before buying any used car."