The automatic budget cutting set for March 1 would hamper the government’s ability to protect the public in a range of areas, according to several warnings that were sounded Wednesday.

The Department of Homeland Security said sequestration “would roll back border security, increase wait times at our Nation’s land ports of entry and airports, affect aviation and maritime safety security, leave critical infrastructure vulnerable to attacks, hamper response time” and weaken cybersecurity protections.

In a letter to Rep. Bennie G. Thompson (Miss.), the ranking Democrat on the House Homeland Security Committee, DHS Secretary Janet Napolitano said frontline law enforcement personnel would have to be furloughed for a total of 14 days and the department might have to lay off employees.

The letter did not specify the potential scheduling of furloughs, but the Defense Department, facing similar cutbacks as are nearly all federal agencies, has said it would spread out the unpaid furlough days starting in April through the remainder of the fiscal year that ends Sept. 30. Furloughs could not begin until after a 30-day notice period and certain aspects are subject to bargaining, in unionized workplaces.

“This letter brings into sharp focus the devastating effect the sequester will have on our homeland security,” Thompson said in a statement. “The sequester, which the Republicans seem unwilling to prevent, will lead to fewer border patrol agents, longer security lines at airports, and far less resources for cybersecurity–which, just last night, the President highlighted as a critical area of importance.”

Colleen M. Kelley, president of the National Treasury Employees Union, which represents Customs and Border Protection employees, said in a statement that budget cuts in that DHS component, “pose real-world dangers for the range of critical CBP duties and inevitably would have a ripple effect throughout government, since CBP is the second-largest generator of federal revenue, behind only the Internal Revenue Service.”

Meanwhile, Democrats on the House Appropriations Committee issued an assessment of the impact on a variety of government functions, in some ways expanding on an assessment released last week by the White House.

“This across-the-board cut will slow economic growth and job creation while cutting critical services and investments,” a summary of the report said.

The report said, for example, that furloughs of air traffic controllers “would result in reduced air traffic control, longer delays, and economic losses for air transportation, tourism and the economy as a whole,” while furloughing meat and poultry inspectors would force thousands of establishments “to shut down or operate fewer hours—costing the industry, grocery stores, restaurants, billions of dollars.”

The report also cited the potential for cuts in programs ranging from food assistance programs to medical research, and from military readiness to processing claims for Social Security benefits.