HOUSTON — As Southeast Texas residents emerged by the thousands from shelters, motels and friends’ houses to return to flood-damaged homes, others remained in the grip of the crisis on Friday, cut off by still-rising floodwaters and living without running water for a second day.

In Houston and the surrounding area where the historic inundation from storm Harvey was mostly receding, people took to trucks and boats to get back into their neighborhoods, and many were appalled by what they found.

Getting their first post-Harvey look at their northwest Houston home, where the water had risen to more than five feet inside, Larry and Suzette Cade stood at the front door, holding hands and crying.

“I just feel so sad and empty,” Mr. Cade said.

To the east, parts of Beaumont and surrounding communities remained isolated, with roads impassable and the Neches River still swelling, rising eight feet higher than the previous record. It is not expected to crest until Saturday. The pumps providing fresh water to Beaumont, a city of almost 120,000, were knocked out by floodwaters on Thursday and remained shut down on Friday. Officials said they did not know when the system might be repaired.