Democrats are demanding a probe into the Federal Emergency Management Agency's failure to help Vieques, Puerto Rico, rebuild its only community health care center, which was destroyed by Hurricane Maria in 2017.

Even though the facility historically lacked a formal "hospital" designation, it housed the small island's clinic for veterans as well as the only labor and delivery room in Vieques, located about seven miles off Puerto Rico's eastern coast.

Democrats in the House and the Senate are now urging the Office of the Inspector General to investigate FEMA's faltering efforts, which have left the island-municipality without a hospital for years now.

"It is unacceptable that U.S. citizens in Puerto Rico continue to lack access to high-quality critical health services years after a disaster, and that FEMA has failed to take rapid and robust action," said a letter sent to Joseph V. Cuffari, the inspector general at the Department of Homeland Security, on Monday and signed by Sens. Bob Menendez, D-N.J., and Elizabeth Warren, D-Mass., as well as Reps. Nydia Velázquez, D-N.Y., Raúl Grijalva, D-Ariz., Bennie G. Thompson, D-Miss., and Peter DeFazio, D-Ore.

Joined w/ @SenWarren @SenatorMenendez @homelanddems @nrdems @transportdems in writing to @DHSOIG to conduct a review of Vieques' health center. @fema's failure to rebuild the facility is denying our neighbors in PR critical health services & is wrong. No more! pic.twitter.com/OOAVJcKFay — Rep. Nydia Velazquez (@NydiaVelazquez) December 16, 2019

In May, lawmakers gave FEMA three weeks to explain to Congress why the agency lacked concrete plans to help rebuild the facility. Since then, Congress has not yet received a written response from FEMA, according to Menendez.

"With fewer than three weeks before the end of the year, we have not seen indication of progress," lawmakers wrote.

FEMA spokesperson Lizzie Litzow told NBC News in a statement that the agency "validated the repair and replacement cost estimates" back in May to replace what the shuttered hospital lost over two years ago.

The move came as an effort to resolve the discrepancy between repair costs and the amount of funds approved. FEMA had originally approved $46 million to rebuild the Vieques hospital, even though estimates said repairs would cost $70 million, according to lawmakers.

"The scope of work is based on a replacement medical clinic facility, not a hospital," said Litzow, adding that the project "is expected to be validated soon.”

In the meantime, the agency has invested at least $5 million into a temporary hospital facility. More than half of that money, about $3 million, was used to build a temporary dialysis center in Vieques.

But that doesn’t mean Vieques has consistent access to health care services, especially since residents only have access to a handful of health specialists on the small island.

To get the services they need, people in Vieques have two options — wait for certain health specialists to visit or commute to the main land of Puerto Rico.

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, unpredictable trek for patients.

In their 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.

Lawmakers labeled these kinds of delays as "especially disturbing" given that Vieques residents suffer from "cancer rates close to 30 percent higher" than the rest of Puerto Rico. Earlier this year, lawmakers including Rep. Alexandria Ocasio-Cortez, D-N.Y., urged the Senate to authorize funding for an environmentally safer cleanup of the island, which was a former military testing ground."

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

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