As the cleanup continues from this month’s torrential rain storms and flooding in Texas that left more than 120 dead, recently departed officials from the Federal Emergency Management Agency (Fema) say the organization is dangerously underresourced and overstretched in the event of further natural catastrophes.

A mass staff exodus, plunging morale and a loss of key leaders has left the main US disaster-relief organization ill-equipped to cope with an anticipated deadly spate of storms in the current hurricane season, former agency insiders say.

Fema’s weakness, exacerbated by grant cuts imposed by the Trump administration and the loss of institutional knowledge in strategic leadership positions, will be exposed if the nation is faced with more than one disaster simultaneously, according to Michael Coen, the agency’s former chief of staff.

In an interview, Coen – who left his post in January after Donald Trump took office – said the officials at Fema had been preparing contingency plans that would enable the agency to meet the demands of hurricane season, which generally runs from early June until the end of November, with fewer resources.

“They understand that they don’t have the resources they’ve had in past years, whether it’s funding or even some contracts have lapsed,” he said. “They are trying to make decisions so that they can handle multiple events at one time.”

But since Trump’s inauguration, the agency has seen an estimated 2,000 departures through resignations or retirements, which may have rendered it incapable of coping with the widespread carnage likely to be wreaked by a succession of tropical storms.

“I’m concerned that Fema is going to be at a disadvantage because they don’t have the resources to respond to the disasters we know could happen, which could be two or three concurrent disasters at the same time,” said Coen.

“Fema has eroded capacity since President Trump became president. Staff have departed. There have been cuts to grant programs and they are going to be running into a financial challenge with the disaster relief fund, because the president hasn’t requested supplemental funding from Congress.”

Coen – a disaster relief career official who was also Fema’s chief of staff during Barack Obama’s presidency – said the cuts could mean the agency running out of funds to respond to disasters by the end of this month.

“Fema is currently supporting the state of Texas with the flooding and the urban search and rescue. But if in a week or two they also have to respond to a hurricane in the Gulf coast or an earthquake on the west coast, Fema is not going to be able to meet the expectations of the American people.”

The concerns over Fema’s state of readiness come amid signs that Trump may have had a change of heart about the agency’s future after months of signaling that he favored its abolition.

Last month, he said the administration planned to “phase out” Fema after the current hurricane season to put more responsibility on individual states to respond to disasters.

He previously described the agency – established in 1979 by Jimmy Carter with the goal of coordinating the US government’s response to disasters – as “not good” and said he would “recommend that Fema go away”.

But ahead of Trump’s Friday visit to the worst-hit Texas flood areas, White House officials indicated that eliminating Fema entirely was no longer under consideration, the Washington Post reported.

The newspaper quoted an unnamed official as saying changes would probably amount to “rebranding” the agency while stressing the leadership role of the states in disaster response.

Kristi Noem, the homeland security secretary – who has overall responsibility for Fema and has chaired a review council looking into the agency’s future – said in the wake of the Texas floods that Fema would be “eliminated as it exists today and remade into a responsive agency”, a hardline stance that nonetheless stopped short of abolition.

Coen said the Texas floods had proved Fema’s worth: “This flood is a defining moment and brings clarity for the necessity of the Federal Emergency Management Agency. Fema is an essential agency for the federal government to support states and support the American people in their greatest time of need.”

But he said grant cuts had rendered it less effective and may have caused “an unnecessary loss of life” in the Guadalupe River area of the Texas Hill Country, the worst-hit flood region.

“One of the grant programs they cut was the Building Resilient Infrastructure Communities, which was a program that would have funded things like the siren system to line a river like the [Guadalupe] in Kerr county,” he said.

“Not that many people needed to lose their lives if more mitigation measures had been put in place. With the president cutting a grant program that provides federal funding to increase mitigation in the country, it only is foreboding for the future on what could happen to other communities if they don’t mitigate and they don’t have access to federal funds.”

The picture of an agency undermined by the Trump administration’s hostility was corroborated by a former mid-level Fema official, who told the Guardian that staff had left because they felt disrespected.

“It’s no secret that a lot of high-level leaders have left the agency,” the ex-official said. “It’s clear that Fema has lost a lot of leadership capability.”

Among those who have left are Tony Robinson, who was Fema’s head administrator for the region that includes Texas, as well as his deputy. Also recently departing was Robert Samaan, the administrator for the region that covers Florida and several other states in the hurricane-prone south-east.

“Those are two of the three most critical regional administrators for hurricane season, and for them to leave at this time leaves people shaken for sure,” the former staffer said.

“The lack of experienced leadership is certainly going to hamstring efforts. It’s not to say that there aren’t other good leaders who will step up. But LinkedIn is littered with people whose names I knew who have left.”

The departure of 16 senior executives was announced on a single day in May.

Compounding the problem is the damage to the morale of those remaining from what insiders say is the scornful attitude of Noem and Fema’s acting administrator, David Richardson, a former marine artillery officer with no previous experience in disaster management.

Richardson, who has been in the post since May, caused a stir among senior staff when he said during a briefing that he did not know there was a hurricane season. It was unclear if the comments were meant as a joke.

Richardson was installed after Noem ousted his predecessor, Cameron Hamilton, after he told a congressional hearing that he did not favor Fema’s abolition. The new administrator also threatened to “run right over” any staff members who resisted reforms.

“I, and I alone in Fema, speak for Fema. I’m here to carry out the president’s intent for Fema,” he reportedly said.

Coen affirmed the picture of staff leaving due to fears for Fema’s future. “The reason many employees have departed since January 20 is because they had a fear that they were going to lose their job,” he said. “Also, they didn’t feel respected by the current administration. The current employees still there are supporting each other, but if they feel they are not getting support and understanding of how much they sacrifice when they go to disasters, it does have an impact on their mental health and wellbeing.”

Noem, meanwhile, has drawn criticism for issuing a decree requiring that any expenditures or contracts worth $100,000 or more are submitted to her for prior approval – a requirement that critics say could impede rapid disaster response.

“Typically, pre-Trump, a decision like that would come at a much lower level than the secretary of homeland security so you could get out and mobilize,” the former official said.

“It’s just unconscionable that you would centralize a decision like that, [which] truly, on reflection, would have led to the loss of life, or at least the loss of the ability to find the remains of the victims.”

The Department of Homeland Security has publicly defended the directive as necessary to root out “waste, fraud and abuse” and deliver “accountability” to US taxpayers.