Environmental activist Erin Brockovich-Ellis, who was immortalized by actress Julia Roberts in a movie about her life, was arrested on Friday for boating at Lake Mead, Nev., while under the influence of alcohol, authorities said on Sunday.

Brockovich, 52, who displayed several signs of being drunk, was arrested by a game warden with the Nevada Department of Wildlife, while struggling to dock her boat at the Las Vegas Boat Harbor, a release cited by ABC News said.

Her breath tests showed that her blood alcohol level was twice the legal limit.

"She was not sure how to maneuver the boat into the dock," Nevada Department of Wildlife spokesman Edwin Lyngar told Associated Press. "It's a simple thing if you can think clearly. But if you add alcohol and unfamiliarity of the area, it can all cause serious problems."

Brockovich was released from the Clark County Detention Center after being fined $1,000. Under Nevada law, boating while intoxicated can draw a fine of $1,000 to $2,000 if it is a one-time offense.

The environmentalist issued a statement on Sunday apologizing for drunk boating, adding that public safety was not at risk as she was not operating the boat in open waters.

"At no time was the boat away from the dock and there was no public safety risk," she said in the statement obtained by AP. "That being said, I take drunk driving very seriously, this was clearly a big mistake, I know better and I am very sorry.

"After a day in the sun and with nothing to eat it appears that a couple of drinks had a greater impact than I had realized," she said.

Lyngar said Brockovich’s arrest highlights the dangers of boating while intoxicated and pointed out that half of all fatal boat accidents are alcohol-related. "Too many people think drinking and boating go together," he said, according to Fox News. "We don't have a problem if people drink. Just have a designated operator."