Baltimore County Executive Jim Smith said the water at the height of flooding was knee- to chest-deep in some places and damaged homes and cars. No injuries or medical emergencies were reported, although crews did rescue several people.

"The only people who had to be rescued were those who went in the water," Smith said.

Baltimore City public works crews stopped the flow to the break, which occurred about 4:30 p.m., about two hours later, said Don Mohler, a spokesman for Smith. By 8:30 p.m., the water had dropped to a maximum of 6 to 8 inches, Smith said.

Scott Peterson, a spokesman for Baltimore Mayor Sheila Dixon, said city public works crews were working Friday night to turn off secondary water valves in the area.

Television news reports showed flooding along some streets, with water entering the ground floor of some homes, cars submerged up to the door handles, some residents in boats and others wading to higher ground. The images also showed part of a two-lane road washed away by the break.

Baltimore County issued a statement late Friday saying as many as 100 homes appear to have suffered basement flooding and two people were transported to a hospital with minor complaints.

Fire and public works crews were going door to door pumping basements. Residents in areas where the flooding has receded were being allowed into their homes although some areas still were under several inches of water. The water main break also destroyed a large section of Broening Highway and the area surrounding the damage will be closed to traffic, the statement said.

Baltimore County police spokesman Bill Toohey said officers would patrol the area overnight because the flooding had caused some power outages and prevented residents from getting into their homes.

Smith said officials expected to have water pressure back to normal and power fully restored in several hours. Smith said about 800 homes were without power Friday night. Baltimore Gas & Electric spokesman Rob Gould said the flooding did not appear to have damaged any gas mains.

Connie Nall, 49, said the water knocked out power to her home but didn't flood it. She planned to spend the night at her brother's house nearby. Nall said she found out about the flooding when people called her at work. When she got home, she said, "I saw the water shooting up."

"I kept thinking, oh these poor people, they're going to get their cars messed up," Nall said.

David Scott, director of the Baltimore City Department of Public Works, said the pre-stressed concrete main was installed in the 1970s and would have to be drained, excavated and examined before the cause of the break could be determined.

Rick Abbruzzese, a spokesman for Gov. Martin O'Malley, said the Maryland Emergency Management Agency was monitoring the situation.

"The state will obviously be assisting in cleanup," Abbruzzese said.

The state would assist families with property damage, similar to aid offered after Tropical Storm Isabel damaged homes in 2003, also in eastern Baltimore County, the spokesman said.

Sen. Barbara Mikulski, D-Md., issued a statement Friday evening calling the break a disaster.

Mikulski said she had contacted Smith about "working together to meet the immediate needs of the families and businesses of Dundalk as well as the long-range problems caused by our aging infrastructure."

O'Malley visited the scene and pledged state resources to help the county and those affected recover, saying officials from the Maryland Insurance Administration would help residents make claims.

Enlarge By Karl Merton Ferron, AP Jasmine Cook, left, and Lindsay McAnulty head down a back alley to try clearing a drain during a flood from a water main break in the Dundalk, Md. area on Friday.