WASHINGTON — California public-works official Bob Beaumont says the $2.1 million he may get from President Obama's stimulus plan "isn't going to make a lot of difference" in a county with $40 million in "shovel-ready" projects.

"It seems like the federal stimulus is trickling down very slowly," says Beaumont, chief assistant director of public works for Marin County, north of San Francisco. "My feeling is it's not finding its way into the economy as quickly as it should."

The $787 billion package Congress passed in February is having less impact than economists expected in pulling the U.S. out of the worst recession in at least 50 years. About $111 billion in planned infrastructure spending is arriving so slowly that recovery in the final six months of 2009 may be weak.

"Most of the stimulus still hasn't yet reached the real economy," said Robert Solow, professor emeritus at the Massachusetts Institute of Technology in Cambridge, who won the 1987 Nobel Prize for economics. "It will help us a lot in the second half of the year. But given the collapse in consumer spending, business investment and state and local government spending, I think it's premature to be getting optimistic."

Jim Ryan, chief executive officer of W.W. Grainger Inc., a Lake Forest, Ill.-based distributor of building-maintenance supplies, isn't being carried away by the stimulus either.

"We haven't seen it yet," he said in a May 20 interview. "We won't start seeing some of that money till late this year, early next year."

Jared Bernstein, chief economist for the office of Vice President Joe Biden, which is overseeing the program's implementation, defended the pace so far, saying the administration wants to make sure money isn't wasted.

"We're hitting the right balance between speed and oversight," he said, adding that spending will "ramp up" in the next three months. "The timing is good."

Workers surprised economists by saving rather than spending the first dollops of cash they received in their paychecks under the plan, as retail sales fell short of forecasts in April. States, meanwhile, have been slow to take advantage of the emergency aid contained in the first phase of the stimulus.

The spending in stage two, including outlays for infrastructure and budget assistance for the states, probably will have greater impact because it will go right into the economy, rather than being set aside in savings.

"This is the moment of truth for the stimulus," said Mark Zandi, chief economist at Moody's Economy.com. "We've got to see it working soon."

Nigel Gault, chief U.S. economist at IHS Global Insight, sees the economy eking out a 0.2 percent annualized advance in the third quarter, thanks to the Obama plan. Without the program, Gault says there would be a 2.4 percent contraction. The economy contracted at a 5.7 percent pace in the first quarter, capping its worst six-month performance in five decades.

Jim Owens, chief executive officer of Peoria, Ill.-based Caterpillar Inc., said his dealers are seeing some benefit.

"People are starting to bid work again," Owens, whose company is the world's largest maker of bulldozers and earth-moving equipment, said on NBC's "Meet the Press" May 31. "It'll have a positive impact and I think we'll start to see that kick in through the summer and into the fall."

The continuing travails of the states may blunt some of the impact of the federal spending. Under the program, states have to submit requests to Washington for the roughly $144 billion set aside to help them balance their budgets. So far, 20 have been approved.

Politics has blocked the arrival of stimulus money in some states, with several Republican governors refusing funding on principle. But even states that are more open to the funds have been slowed by the need to alter unemployment-compensation programs to bring them in line with new federal requirements.

The kick to consumer spending from the package has also proven smaller than economists expected. Retail sales fell for the second straight month in April, dropping 0.4 percent.

If consumer spending remains weak through the third quarter, "that would postpone the recovery into next year," said Allen Sinai, chief economist at Decision Economics in New York.