San Lorenzo, Puerto Rico (CNN) Nelson Maldonado had already gone days without running water or electricity, after Hurricane Maria ravaged Puerto Rico.

On Thursday, he went to check on his wife's 95-year-old grandmother, Rosa M. Torres, who was also living without power through sweltering heat and humidity.

She lives across the river from him, in the mountainous town of San Lorenzo, which lies about a 40-minute drive from San Juan.

To get there, Maldonado had to ford a river in knee-deep water, using a cable to guide him across. The concrete bridge connecting the two sides had collapsed and floated downriver in a flash flood triggered by Maria.

Maria pummeled San Lorenzo. Massive chunks of the bridge had drifted more than a football field's length downstream. Roofs and sides were blown off homes. Hurricane winds ripped the paint off several buildings. Living rooms are now exposed to the elements. A school was littered with fallen trees as horses occupied the gymnasium, leaving piles of feces behind.

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