The credit crunch has officially arrived on campus: In a new survey, private colleges report their students are finding it significantly harder to secure the private loans they need to pay tuition bills. Furthermore, nearly half of colleges say some students have been forced to take time off or go part-time as a result.

The survey, released Oct. 21 by the National Association of Independent Colleges and Universities, confirms anecdotal evidence that the federal financial aid system so far has held up reasonably well during the financial meltdown.

But the survey paints a more troubling picture for students who need private loans to supplement their federal ones.

"We had not expected to find incidences of students already stopping and dropping out," said Sarah Flanagan, vice president for government relations at NAICU. "There are certainly a concerning number of students who have had to change their educational plans because of a lack of credit."

Three-quarters of the 504 schools surveyed reported more requests for institutional aid this year, and despite the largest cohort of 18-year-olds since the Baby Boom, one in five colleges reported a smaller incoming class than expected.

Only about one-quarter of American college students attend private or independent colleges, and they typically have to borrow more than students elsewhere. But they're also generally considered more attractive lending candidates, Flanagan said, because of factors such as higher graduation rates.

According to last year's numbers from the College Board, the average list price at public four-year colleges was $6,185, compared to $23,712 at private four-year colleges.

That's why the findings are troubling: If private college students can't get loans, students at public, community, and for-profit schools are struggling at least as much.

The survey was conducted in September, before the latest tightening of credit markets.

"There are only so many options. We've awarded them the maximum grants and scholarships and loans," said Sue Standley, the financial aid director at Augustana College in Rock Island, Ill., which recently announced next year's tuition hike of 3.9 percent the lowest in 25 years six months earlier than usual to help students plan ahead. Tuition, fees, room, and board this year run $37,800.

Standley said about 25 students there out of 2,500 total have been unable to secure student loans because they don't have creditworthy co-signers, and a handful may have to drop out.

Experts agree prompt action last spring by Congress and the Bush administration successfully averted major problems with the federal loan program, chiefly by buying up loans from lenders and providing them capital to make new loans. But student lending through the government is capped, so many still turn to private loans for college costs.

Those loans amounted to at least $18.5 billion in 2006, according to the most recent figures from the College Board. Such loans are the fastest-growing segment of financial aid, surging nearly 900 percent in volume over the last decade.