A D.C. nonprofit is suing the Trump administration seeking to halt the resurfacing being done at the Lincoln Memorial Reflecting Pool.

The Cultural Landscape Foundation, an education and advocacy organization, is asking for a temporary preliminary injunction in a lawsuit it filed Monday with the U.S. District Court for the District of Columbia. The organization wants to halt the work the Interior Department is doing, saying in the suit that the Trump administration failed to undergo required reviews for changing historic sites before applying a blue tint to the bottom of the pool.

“Every day that the resurfacing continues, the historic character of the Reflecting Pool is being further and fundamentally altered,” the Cultural Landscape Foundation wrote in the lawsuit, which describes the pool as “one of the most iconic designed landscapes in the world.”

The challenge is the latest from D.C. organizations meant to stop or slow President Donald Trump’s renovations to historical sites and buildings in the city. In March, a federal judge ruled that the administration needs congressional approval before continuing with its plans to construct a massive, ornate ballroom where the White House’s East Wing once stood.

Despite negative public comments and lawsuits, Trump’s handpicked National Capital Planning Commission has given the green light for the ballroom and unanimously approved the president’s plans for a 250-foot arch at Memorial Circle, near Arlington National Cemetery.

The lawsuit brought against the revisions being made to the Reflecting Pool references a provision of the National Historic Preservation Act, which states that reviews must take place before changes are made to historic sites.

“The Reflecting Pool and its surrounding landscape are listed in the National Register of Historic Places as part of the National Mall Historic District. Accordingly, before making any changes to the Reflecting Pool, Defendants were obligated to follow the Section 106 procedures. This includes consulting with various interested parties such as experts and nonprofit organizations with relevant expertise that provide input on proposed changes,” the lawsuit reads.

Charles A. Birnbaum, president and CEO of the Cultural Landscape Foundation, told The Washington Post that he was concerned about the potential consequences of allowing a president to unilaterally change monuments and the landscape of D.C.

“This is about process more than anything else,” Birnbaum said.

The Interior Department, which is overseeing the renovations, did not immediately respond to a request for comment from NOTUS. However, the department defended the project to the Post.

“The Department is proud of the work being carried out by our Park Service to ensure this magical spot can be enjoyed for not only our 250th, but for many generations to come,” the department said in a statement, referring to the coming anniversary celebrations of the country’s founding.

The New York Times reported that while Trump initially said the renovations being done by contractor Atlantic Industrial Coatings would cost $1.8 million, the cost of the project has now ballooned to $13.1 million. The Interior Department told the Times the increased cost was necessary to “expedite” completion.

Atlantic Industrial Coatings was hired to repair leaks from the pool, waterproof the bottom and paint it “American flag blue.”

“It’s going to last many, many years and it’s going to have no leaks,” Trump told reporters last week about the renovations.