If Congress can’t avoid a government shutdown over immigration policy this week, the most visible effect in Maine would be the closure of Acadia National Park.

Heating and housing assistance for the poor also might be vulnerable to disruption, although state officials have been unable to get their federal counterparts to clarify the situation.

Federal employees also would not receive paychecks, some civilian workers could be furloughed, and there could be delays in getting passports.

Otherwise, Mainers would notice few changes, at least at first, because the state has relatively few federal facilities and employees.

The federal government has been careening toward a shutdown this week, after President Trump scuttled a bipartisan deal to prevent the deportation of U.S. residents brought into the country illegally when they were children, using derogatory language about Haiti, El Salvador and certain African countries.

Republicans control both houses of Congress, but they still need Democratic votes to pass a temporary spending measure in the Senate, and Democrats have been insisting that the measure include provisions preventing the deportation of the so-called “Dreamers.” If they can’t reach a settlement, the government will shut down at midnight Friday for lack of funds.

Essential government services and those provided by independent agencies or guaranteed by law will continue to operate. The Postal Service will deliver mail, the Amtrak Downeaster will make its runs, air traffic controllers will be working, and the military will operate as usual.

Social Security, Medicare and food stamp benefits will be distributed, and veterans will have access to most medical services at the Togus Veterans Affairs Medical Center and other VA facilities.

Federal courts would be open, although civil cases could be postponed if the shutdown began to exhaust non-annual funding appropriations. Food inspectors, federal law enforcement agents and members of Congress would still report to work.

But great swaths of the federal government considered non-essential would close down until the deadlock in Washington was broken. Exactly how each department and agency handles this varies from shutdown to shutdown and administration to administration.

Also, some federally funded programs administered by Maine state agencies could potentially be disrupted if the federal employees who approve and make financial transfers are furloughed, including the Low Income Home Energy Assistance Program, known as LIHEAP, and Section 8 housing payments.

“We asked what will happen if there’s a shutdown and they told us ‘We don’t know, but when it happens we will give you some guidance,’ ” said Peter Merrill, interim director of the Maine Housing Authority, which administers both of those programs. “So it’s possible that there would be a problem, but I don’t see it as particularly likely.”

The extent of the potential closure of Acadia National Park was unclear Wednesday. During the last shutdown, for 16 days in 2013, park managers closed the gates, parking lots and roads and canceled all in-park activities and ranger-led programs. Campers were given 48 hours to leave the grounds, but rangers didn’t try to stop pedestrians from walking in and around the park.

Other potential effects of a shutdown:

• There are nearly 11,000 executive branch federal jobs in Maine, and most of the people holding them – whether essential or not – would not get paychecks. “Essential” personnel would be paid retroactively once the impasse was resolved. If the shutdown persists, some would be furloughed. This is what happened to 35 Veterans Administration staff at the Togus VA medical center nine days into the 2013 shutdown, closing an office that provided in-person benefit consultations to veterans.

• Civilian federal workers might be furloughed. Days before the 2013 shutdown, many of the more than 4,700 civilian workers at the Portsmouth Naval Shipyard in Kittery did not know whether they would be able to report for work. Guidance on these issues might come late from Washington this time around as well.

• Some state employees whose positions are 100 percent funded by the federal government could be temporarily laid off. In 2013, Gov. Paul LePage laid off 56 such workers at the Department of Health and Human Services a week into the shutdown; most of them worked at the office that processes disability claims. Another 406 National Guard technicians also were briefly furloughed in the first days of the shutdown, but were recalled shortly thereafter. If a shutdown persisted for weeks, however, over 2,700 state employees could be affected.

• Passport and visa applications would be delayed. In 2013, the State Department stopped processing about 200,000 passport applications during the shutdown, and tens of thousands of visa applications from foreigners accumulated unprocessed each day.

• Federal grants to cities and states would be delayed. The federal government provides tens of millions in grant funding to Maine cities, towns and state government for a wide variety of purposes, from environmental protection to the restoration of contaminated industrial sites, to the funding of home heating assistance and schools. There would be few noticeable effects in the first week or two, but a shutdown lasting weeks or months would eventually trigger ripple effects that would disrupt many aspects of civic life, including parts of state government.

Colin Woodard can be contacted at:

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