In a brief news conference outside a Baltimore hospital, the Pasadena Republican said his blood-alcohol content was measured at 0.2 percent after Wednesday's crash. The legal limit is .08, according to state law.
"I deeply regret my actions and ask for your forgiveness," Dwyer said, adding that no one should operate a car or boat while under the influence of alcohol. He said his thoughts are with the others injured in the collision.
Dwyer, 54, another adult and four children were seriously injured in the collision, according to Department of Natural Resources Police and the Anne Arundel Fire Department.
A seventh person suffered less serious injuries, and two others — an adult and a child — refused treatment.
Dwyer was in a wheelchair and wore a neck brace and a cast around his left foot during the news conference outside the Maryland Shock Trauma Center. He spoke from prepared statements and answered no questions from reporters before being wheeled back into the hospital by a nurse.
Sgt. Brian Albert, a spokesman for the Department of Natural Resources Police, said he did not know how Dwyer was aware of his blood alcohol content. Natural Resources investigators collected a blood sample from Dwyer and are waiting for analysis results from a state lab, which could take 30 days, he said.
Pending the analysis, DNR police will determine what charges — if any — will be filed, Albert said.
"We're in no hurry to expedite the investigation," Albert said. "It takes a long time to reconstruct an accident that occurs on the water, we have both vessels and we don't think any of the parties are going anywhere."
None of those hospitalized are suffering from life-threatening injuries, Albert said.
The loud noise of the crash — followed by screams — alerted neighbors in the waterfront community by Long Point, residents said.
"I thought it was a bomb. I never heard anything so loud over here," said Janet Bemkey, who lives with family there.
Her daughter, Lisa Willis, a nurse, was among those who rushed out to help. She saw her neighbor Andrew Wendell getting on his boat and joined him.
Describing the accident scene, Willis said, "The whole front of the boat was gone. It was not there."
Saying that everyone was pulled to safety, she added, "We are calling it 'miracle on the Magothy.'"
She said one of the children was about 30 feet from her boat. "Randy Harbin dove in to save her and brought her back to the boat," Willis said.
The children — some of whom were being pulled on a tube — were scared and crying, and a "couple of the kids were asking if they were dying," she said.
The collision highlights an issue that state officials have sought to combat for years. Last year, DNR police arrested 124 people for operating a watercraft while intoxicated, according to agency statistics. In the last 10 years, the annual arrest count has varied from 75 in 2002 to 237 in 2007.
Last year there were 186 reported boating accidents, involving 156 injuries and 24 fatalities, according to the agency. Alcohol was a factor in 2 percent of all accidents, but in 25 percent of accidents involving a death. Of the 24 boating fatalities last year, alcohol was a factor in six.
Given the popularity of tubing in the Magothy, the crash also revived concerns about boat speeds — though the speed of the motorboats involved in the accident is unknown.
"I think this accident calls attention to rethink some of that," said Paul Spadaro, president of the Magothy River Association. "We should perhaps reconsider assigning separate areas for tubing, separate from boating activity."
There is no weekday speed limit on the part of the Magothy near Cornfield Creek, where the crash is believed to have taken place, Albert said. The limit is 6 knots on Saturdays, Sundays and holidays, he said.
Albert said Dwyer had one passenger on the 26-foot Baja closed-bow runabout, identifying him as John Edward Moran IV.
Moran has been a Republican candidate for election previously in Anne Arundel County.
Nine people — four adults and five children — were aboard the motorboats when they collided about 7 p.m., causing one of the boats to sink, said Albert. The boat that sank — the Baja — has since been recovered by a tow vessel. The other boat, an 18.5-foot Bayliner runabout, was seriously damaged but made it to shore, police said.
"The cause of the collision is still under investigation," Albert said. "A number of investigators are on a fact-finding mission."
Three nearby boats responded to pull those injured from the water, taking most to the Gibson Island area, where they were met by emergency responders who had been called to the scene by someone on shore, said Lt. Keith Hamilton, a county fire spokesman.
Dwyer and a 40-year-old man identified as Earl Mitchell were taken to the Maryland Shock Trauma Center. Dwyer was listed in fair condition shortly before the news conference, a hospital spokeswoman said Thursday. Mitchell was discharged early Thursday.
Albert said the Bayliner was piloted by Randy Harbin, and Mitchell, a neighbor, was the only adult passenger. He declined to name the children but said there were five with them.
Hamilton said Harbin, 51, was taken to Baltimore Washington Medical Center with less serious injuries, Hamilton said. Hospital officials said a Mark R. Harbin had been discharged.
Two boys, ages 12 and 7, and a 5-year-old girl were transported — the girl by Maryland State Police helicopter — in serious condition to the Johns Hopkins Pediatric Trauma Center, Hamilton said. A 10-year-old boy was taken to Johns Hopkins Hospital's emergency room.
One adult and one child refused treatment at the scene, Hamilton said.
Del. Nic Kipke, a Pasadena Republican, said he got a flood of phone calls and texts after the collision from friends who live in the area, who told him that Dwyer's boat was involved in the accident.
Kipke wished everyone involved a speedy recovery. "Delegate Dwyer and I have gotten to know each other over many years, and my thoughts and prayers are with him and the other families that have been injured," he said.
Dwyer, one of the most conservative members of the state legislature, has been in the House of Delegates since 2003 and is a member of the Judiciary Committee. He is a strong supporter of gun rights. In the last session, Dwyer said his only goal was to block the passage of same-sex marriage.
He was born in Annapolis and graduated from Glen Burnie High School in 1976. He is married with three children.
What the collision and Dwyer's admission that he was drinking will mean for his political career is unclear, said Dan Nataf, director of Center for the Study of Local Issues at Anne Arundel Community College.
Dwyer's district has become increasingly Republican, and a strong candidate might be able to "topple him in the primary," Nataf said. He said some of Dwyer's political positions "seem to be religiously imbued and morally unambiguous," and appeal to voters who have similar beliefs.
"I think it could affect him in that people will scratch their heads and say: 'Is there a Don Dwyer we didn't really know?'" Nataf said.
He said, nevertheless, that "people are very forgiving ... [and] may say, 'It's one time. There is nobody who stood up on certain issues the way [Dwyer] has.'"
Gov. Martin O'Malley declined to comment Thursday on Dwyer's involvement in the collision, but through a spokeswoman said he "is very concerned for those who were involved in the crash and wishes for a speedy recovery."
House Speaker Michael E. Busch was not available for comment.
"Many questions still remain after Delegate Dwyer's statements, but we appreciate the candidness of his remarks and expect that more answers will be forthcoming in the near future," the Republican State Central Committee of Anne Arundel County said in a statement released Thursday night.
Like others, the committee praised those involved in the rescue and expressed concern for the people who were injured.
Baltimore Sun reporters Annie Linskey and Mary Gail Hare contributed to this article.