Public-private partnerships, already a growth area for infrastructure development, could get an even bigger boost if President-elect Donald Trump delivers on his campaign pledge to focus on infrastructure.

These partnerships, often referred to as PPP or P3, enable private entities to invest in public projects such as highways, public utilities, and public buildings. Investors then are paid by the government or from project revenue such as highway tolls.

"It's a burgeoning market primarily because infrastructure needs are always growing," said Steve Park, leader of Ballard Spahr's P3 group. "The need is there, the money is not. So in a lot of places they found maybe the only way to get the infrastructure done is through P3."

Trump has not provided details of his infrastructure plan, Park said. However, he noted, bipartisan infrastructure improvement political momentum already exists. President Barack Obama's administration was "as hot on P3s as any president," Park said.