The claim, first made by New York congresswoman Alexandria Ocasio-Cortez on Twitter, was backed up by California congresswoman Judy Chu and other Democrats following their supervised fact-finding tour.
“When we tried the sink there was no running water. The women said, ‘Oh we were told it’s OK to drink out of the toilet – that’s potable water,’” Pennsylvania congresswoman Madeleine Dean told ABC News.
“One of the women said that she was told by an agent to drink water out of the toilet,” said Texas congressman Joaquin Castro. “These are the conditions that have been created by the Trump administration.”
Although the politicians were asked to surrender their phones before the tour, Mr Castro smuggled a device inside the El Paso Border Patrol station to film and take photos. He said women were crammed into “a prison-like cell with one toilet, but no running water to drink from or wash their hands with”.
The tour, which also included a visit to a Clint, Texas, facility, followed reports from a government watchdog that immigrants were being housed in overcrowded and unsanitary conditions.
Ms Chu said: “I will never forget the image of being in a cell and seeing 15 women, tears coming down their faces as they talked about being separated from their children, about having no running water and about not being able to know when they were going to get out since they had already been there 50 days.
“A woman talked about being an epileptic and not having access to any medicine,” the Democrat added.
“After I forced myself into a cell with women and began speaking to them, one of them described their treatment at the hands of officers as “psychological warfare”, said Ms Ocasio-Cortez. “This has been horrifying so far.”
Video released on Tuesday showed a 12-year-old migrant girl talking about her treatment inside a Border Patrol station in Texas.
In footage obtained by the Associated Press, the girl said children were “treated badly” at the facility and locked away when they cried for their parents. The 12-year-old said and she and her six-year-old sister slept on the floor while held there for two weeks.
It comes as the Border Patrol faces questions about a report by the non-profit site ProPublica claiming sexually explicit comments referencing Ms Ocasio-Cortez were posted on a private Facebook group for current and former border agents.
Posts in the Facebook group, said to have around 9,500 members, also reportedly included jokes about the deaths of migrants.
“This isn’t about ‘a few bad eggs’,” Ms Ocasio-Cortez tweeted in response. “This is a violent culture.”
Matthew Klein, assistant commissioner of the Office of Professional Responsibility for Customs and Border Protection (CBP), called the social media activity “disturbing” and said it violated the agency’s code of conduct.
Mr Klein said the matter had been referred to the inspector general of the US Department of Homeland Security, which has jurisdiction over the CBP.
Additional reporting by agencies
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