In an interview on SiriusXM’s Breitbart News Sunday, an immigration expert predicted that approximately 100 million foreign-born people are expected to be added to the population in the United States over the next 50 years via the country’s legal immigration system.

The interview with Steven Camarota, director of research for the Center for Immigration Studies, followed a report by Breitbart News in which he revealed that 15 million foreign-born, potential voters would be added to the U.S. voting rolls over the next twenty years under current legal immigration levels.

On Sunday, Camarota said that the U.S. will experience an unprecedented level of growth from foreign-born immigrants over the next half-century unless Congress and the Trump administration limit current legal immigration levels and reform the system to one that brings in skilled legal immigrants who are English-proficient.

“If immigration policies aren’t changed, everybody agrees that, at least over the next 50 years, immigration will add about 100 million people to the U.S. population,” Camarota said. “That’s the arrival of about … 1.5, 1.6 million new legal and illegal immigrants over the next 50 years … That will add about 100 million, that’s their children, them, plus their children, taking into account the people who go home, plus mortality.”

Camarota described the probable impact of such an influx of immigrants to America.

“The country becomes much more densely settled, much more populated, and remember, only about 60 counties in the United States, two-thirds, three-fourths of all the people end up in just those 60 counties. That’s an enormous impact on the quality of life in an area like Washington, D.C., you know it might add half a million people to the U.S. population or the county of the D.C. metro area even over the next 30 or 40 years. That certainly does mean a lot more congestion and traffic and so forth.”

Impact will also be seen on voting rolls across the U.S., according to research by University of Maryland, College Park political scientist James Gimpel, who found in recent years that more immigrants to the U.S. means more Democrat voters and increasing electoral victories for the Democratic Party.

According to Breitbart News, “five years of chain migration to the U.S. has exceeded one year of all American births, wherein about four million U.S. babies are born every year.”