PETIT-GOAVE - Hurricane Matthew churned toward the Bahamas early Wednesday with a spreading mix of high winds, heavy rains and a dangerous storm surge, leaving widespread damage and human suffering behind in Haiti's poor, rural southwestern peninsula. At least 11 deaths had been blamed on the powerful storm during its weeklong march across the Caribbean, five of them in Haiti. But with a key bridge washed out, roads impassable and phone communications down, the western tip of Haiti was isolated and there was no word on dead and injured. Forecasters said the high winds, pounding rains and storm surge were already beginning to have an impact in the southern Bahamas as the powerful Category 3 hurricane left Haiti and eastern Cuba behind and marched toward the island chain over open waters Wednesday. A day earlier, Matthew swept across a remote area of Haiti with 145 mph winds, and government leaders said they weren't close to fully gauging the impact in the vulnerable, flood-prone country where less powerful storms have killed thousands. "What we know is that many, many houses have been damaged. Some lost rooftops and they'll have to be replaced while others were totally destroyed," Interior Minister Francois Anick Joseph said. The hurricane also had made landfall Tuesday night near Cuba's sparsely populated eastern tip with no immediate reports of major damage. In Haiti, where international aid efforts were stymied Tuesday because of the lack of access to the hardest-hit areas, many residents of flooded areas seen by Associated Press reporters were wading through shin-high waters. Muddy rivers and tributaries continued to rise as water flowed down hillsides and mountains, making more flash floods and mudslides possible even Matthew tracked away from the country. Matthew was at one point a Category 5 storm, making it the most powerful hurricane in the region in nearly a decade. It blew ashore around dawn Tuesday in Haiti, the poorest country in the Western Hemisphere and a place where many people live in shacks of wood or concrete blocks. Mourad Wahba, U.N. secretary-general's deputy special representative for Haiti, said at least 10,000 people were in shelters and hospitals were overflowing and running short of water. Wahba's statement called the hurricane's destruction the "largest humanitarian event" in Haiti since the devastating earthquake of January 2010. Surging waters ripped away a bridge in the flooded town of Petit Goave, preventing any road travel to the hard-hit southwest. Local radio reported water shoulder high in parts of the southern city of Les Cayes. Milriste Nelson, a 65-year-old farmer in the town of Leogane, said neighbors fled when the wind tore away the corrugated metal roof on their home. His own small yard was strewn with the fruit he depends on for his livelihood. "All the banana trees, all the mangos, everything is gone," Nelson said as he boiled breadfruit over a charcoal fire. "This country is going to fall deeper into misery." Haitian authorities had tried to evacuate people from the most vulnerable areas ahead of the storm, but many were reluctant to leave their homes. Some sought shelter only after the worst was already upon them. Rainfall totals were predicted to reach 15 to 25 inches in Haiti, with up to 40 inches in isolated places. Associated Press writers Ben Fox and Jennifer Kay in Miami, Evens Sanon and Dieu Nalio Chery in Haiti, Ramon Espinosa in Baracoa, Cuba, and Joshua Replogle in the Bahamas contributed to this report.