Almost two years after Hurricane Maria devastated Puerto Rico, the smaller island of Vieques still does not have a hospital.

The Federal Emergency Management Agency has less than three weeks to explain to Congress why the agency has no concrete plans to help rebuild the facility.

The ultimatum comes after Democratic lawmakers sent a letter addressed to FEMA’s acting administrator Peter T. Gaynor on Wednesday, seeking answers as to why “U.S. citizens still cannot access comprehensive medical care” almost two years after the hospital was shuttered due to damage caused by Maria in 2017.

In the letter, the members of Congress reference the case of a 64-year-old cancer patient who waited 32 straight hours — sleeping and eating in her car — to ensure she had a spot on the ferry that takes residents from the smaller island to the mainland to reach a doctor in the capital city.

About 9,000 people live in Vieques and hundreds of people commute to the mainland by boat, which is significantly cheaper than traveling on a plane. While the ride can take between 30 minutes to one hour, unreliable maritime transportation services often leave commuters waiting multiple hours for a boat ride. In addition, bad weather can delay the ferry rides, making a trip to the doctor a long, predictable trek for patients.

“In Puerto Rico, we talk a lot about how we are treated as second class citizens, but the people of Vieques and Culebra [another island off the coast of Puerto Rico] are being treated as third class citizens,” Edgardo Román Espada, president of Puerto Rico’s Bar Association, told NBC News in Spanish.

“The biggest problem Vieques is facing is the abandonment of responsibility by the government. The right to access health care is recognized as a human right — it becomes more urgent to address this when it involves people traveling through air and sea to access health care,” he added.

Sens. Bob Menéndez, D-N.J., Elizabeth Warren, D-Mass., Richard Blumenthal, D-Conn., Edward J. Markey, D-Mass., Kamala Harris, D-Calif., and Kirsten Gillibrand, D-N.Y., signed the letter urging the agency to ”take rapid and robust action to provide the hospital with the resources it needs to rebuild.”

Reps. Nydia Velázquez, D-N.Y., Darren Soto, D-Fla., José Serrano, D-N.Y., and Alexandria Ocasio-Cortez, D-N.Y., also joined the senators’ calls.

Residents of the island of Vieques only have access to a handful of health specialists and services.

“Most people who need to go to the [big] island for medical service try to get on the first boat that leaves,” Elda Carrasquillo, who coordinates health workshops in Vieques through the organization Taller Salud, said.

Vieques turned their only emergency shelter building into a public community health center, known by its Spanish initials CDT, after the previous center was destroyed by Maria, Carrasquillo said.

“Just this week, the landfill has been on fire days and we couldn’t use the shelter to house some of the people displaced by the fire,” Carrasquillo said. “Right now, if we have another emergency, we have no place to shelter people.”

The island of Vieques also has an operating temporary emergency room and a few mobile health centers that provide dental care and dialysis treatments.

Juan A. Muñoz Torres, director of external affairs for FEMA in Puerto Rico, told NBC News in a statement that the agency invested $5 million on building the temporary hospital facility, including “roughly $3 million for a temporary dialysis center brought to the island.”

But that doesn’t mean Vieques has consistent access to health care professionals. Specialists such as pediatricians, nephrologists, gynecologists, among other doctors, sporadically visit the island to provide services.

“After a certain hour, there are no medics around and people depend on a boat to get care,” Román Espada said.

The Puerto Rican government recently relocated the boat terminal that connects Vieques and the mainland of Puerto Rico. According to Carrasquillo, three different companies provide maritime transportation services in that terminal; two of which are private companies.

Many residents have raised concerns over the inconsistency of the service, since the changes were implemented in April.

“On a day like today, there’s just one company operating a ferry that can take up to 78 passengers,” Carrasquillo said. “That’s a problem when around 300 passengers commute here every day, many of whom have no other choice than to go to the mainland to get treatments.”

According to Muñoz Torres, FEMA is waiting on an assessment that will determine how much it would cost to repair the shuttered hospital. The agency expects that such an assessment will help determine final repair costs sometime this month.

So far, close to $5.7 billion have been approved for Puerto Rico under FEMA’s public assistance program, Muñoz Torres said. The funds that end up financing the hospital’s reconstruction are expected to come from this assistance program.

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