Washington Mayancela decided he wanted his life to be degree-free.

He joins legions of well-schooled millennials bucking the trend of college, taking often dirty but well-paid blue-collar jobs.

Coming out of the shadow of the Great Recession, once-plentiful white-collar jobs are still scarce, many replaced by lower-paid service work.

Mayancela, 20, decided two years ago to start his apprenticeship as a steamfitter.

The Staten Island native graduated with his Advanced Regents diploma, a GPA of 4.0, and in the top five at Staten Island’s Ralph R. McKee Career & Technical Education High School. The best colleges came knocking with scholarships. But Mayancela had other plans.

“Oh yes, the scholarships came in,” Mayancela told The Post, “but in the end my decision was more about economics and benefits and job satisfaction. I was 18 and it was a tough decision, but really I am glad I made it.”

And a growing number of other brainy millennials are following Mayancela’s path, according to the experts.

Many of them say they are on cloud nine — in jobs more associated with grime and physical labor than technology, cubicles and office politics. They’re pulling down some of the biggest salaries and best benefits, and in fields with plenty of openings.

Meanwhile, many of their peers, some of them recent grads, are unemployed, underemployed or are swelling the ranks of the huge low-wage service sector.

Mayancela’s pay package after his five-year apprenticeship as a unionized steamfitter in New York City will be $110 an hour.

“We’re seeing a new generation out there who’ve gone to school, some completing four-year college degrees now turning to the construction industry,” Gary LaBarbera, president of the Building and Construction Trades Council of Greater New York, told The Post.

“A record number of young people, many with higher education, are lining up for applications.” These were among the estimated 1,000 who got in line this month in New York City for applications as apprentice plumbers.

And forget about student loans. Actually, candidates for these lucrative blue-collar jobs can show up with a high school diploma. Training in many apprenticeship programs is paid by the employer and union in New York City. “It’s the equivalent of a [free] $50,000 education,” LaBarbera said.

Staffing expert Jason Leverant, president of AtWork Personnel, says blue is the new green. “Honestly, this is where the opportunity is today,” he said.

“Have you ever tried to call a plumber or electrician who will answer the phone right away? There’s such a big opportunity here for millennials to step in,” Leverant added.

How big? There’s a major shortage of skilled and semi-skilled workers nationwide. And according to the Department of Labor, for example, the 10-year projected employment gain through 2022 for carpenters in New York City is 14 percent (24 percent nationwide) with the annual local wage for experienced journeymen nearly $90,000.

Mayancela knows the pain. “Some of my friends I went to high school with have now dropped out of college,” Mayancela said. “They’ve been asking me if there is any way they can get into the construction trades. They want a good career.”