A 41-year-old man with a blood alcohol level nearly seven times over the legal limit drove down the railroad tracks Tuesday, ripping away parts of his Nissan Altima’s undercarriage before stopping, Petaluma police said.

Juan Bamaca‑Velasquez was found about 9 p.m., lying near his damaged car about 350 feet down the Sonoma-Marin Area Rail Transit tracks, police said. Train officials were alerted, although no trains had to be diverted.

Bamaca‑Velasquez, who had been living nearby at a Petaluma homeless shelter on Hopper Street, was arrested on suspicion of driving drunk and on a suspended license.

It was his fifth drunken driving arrest, police said. He had four DUI convictions since 2001 and had spent time in prison for those convictions, police said.

A preliminary test showed he had a blood‑alcohol level of 0.54 percent. Bamaca‑Velasquez remained in custody Wednesday at the Sonoma County Jail in lieu of $25,000 bail.

You can reach Staff Writer Randi Rossmann at 707‑521-5412 or randi.rossmann@pressdemocrat.com. On Twitter@rossmannreport.