Boston — One of America's oldest and most troubled industries - the railroads - is driving a golden spike in a new era.
Spurred by heavy haulings of coal and less government regulation, the railroads are undergoing a resurgence after more than a decade of decline and seem set to be a growth industry in the 1980s.
Trimmer and fitter than before, the nation's ''iron horses'' are also girding to take back some of the freight business lost to the arch-rival trucking industry in the 1970s.
''The decade of the 1980s should be excellent for the railroads, provided we get a recovery and economic growth,'' says Graeme Lidgerwood, a rail analyst at Kidder, Peabody & Co., the brokerage firm.
Revenues for the industry rose 22 percent in 1981 over the year before, to $2 .32 billion. Return on invested capital the past couple of years has been running at the highest rate in at least a decade.
And the amount of goods hauled over the country's spaghetti rail network has been growing: Between 1977 and 1980 tonnage climbed steadily, peaking at a record 918 billion ton-miles (one ton moved one mile). Last year it leveled off at 915 billion ton-miles.
The underpinnings of the current turnabout were laid early in the '70s. Jarred by the bankruptcy of the mighty Penn Central in 1970 and other corporate failures, many railroads began slimming operations and slowly upgrading equipment. Money was poured into new track, trains, and other equipment in anticipation of a freight boom in the 1980s and beyond.
Today, with coal shipments rising, the nation's main rail lines are in better shape than in decades, industry officials contend. The industry also seems to get a boost every time energy prices rise. Studies show railroads to be two to three times as fuel efficient as trucks for hauling goods.
Less noticeable has been the change in management at many companies, with greater emphasis now placed on the bottom line and gearing the railroad to keep up with technological changes in the industry.
''In the last 10 years, the railroads have tried to figure out how to run a railroad,'' says Carl Martland, a research associate at the Massachusetts Institute of Technology's Center for Transportation Studies. ''They have bolstered their ability to manage and control performance.''
But probably the biggest reason for the rebirth has been a change in the ground rules under which the railroads operate. The industry was given a greater taste of freedom under two federal rail reform initiatives, the first in 1976 and a more sweeping measure in 1980. They granted railroads greater latitude in setting rates and entering into long-term contracts with customers - increasing the industry's ability to compete with both truckers and barge operators.
The measures also made it easier for rail carriers to shed unprofitable lines and streamlined the merger-approval process, which, analysts believe, should result in even more consolidation in the industry. As it is, the railroad business, once a patchwork of dozens of big and small carriers, is now grouped around seven major rail systems.
Relatively brisk shipments of coal and some favorable union bargaining has recently restored financial vitality for many lines. The Boston & Maine Railroad , for instance, made money in 1980 for the first time in 23 years. Last year the scrappy New England carrier, mainly a freight line, earned $6.2 million - more than double the year before.
Bankrupt and operating under the supervision of court-appointed trustees since 1970, the B&M eventually expects to emerge from bankruptcy debt free and is in the final stages of being purchased by industrialist Timothy Mellon, one of the Pittsburgh Mellons.
''It sure is nice to be growing instead of retrenching,'' says Alan Dustin, B&M president.
Perhaps most surprising to industry analysts, however, has been the relative turnaround of the long-ailing Consolidated Rail Corporation (Conrail). The Northeastern carrier, a hybrid created by Congress in 1976 from six bankrupt railroads, posted profits of $39.2 million last year after a wrenching $243.7 million deficit in 1980. The company has now gone without federal subsidies for a year.
Even troubled Amtrak, the government-supported passenger rail network, is showing some signs of financial vigor. Despite recent drops in ridership, its transportation revenues jumped 16 percent last year, improving its chances of meeting a congressional obligation of being self-sufficient in operating revenues by 1985.
The more competitive stance of the industry could mean nabbing some freight traffic away from truckers. Although there are no hard figures, analysts believe the railroads are winning some skirmishes against their highway rivals. One sign: While overall truck tonnage has been down, the level of piggyback activity - truck trailers carried on flatbed rail cars - was up more than 8 percent the first five months of this year, compared with 1981.
The recession is pinching rail carriers, reducing their volume. They are also finding some costs rising faster than freight price increases. But in the long run the robust days of the railroads may return again.
''In a broad sense, the rail resurgence is continuing,'' says Marc Gerstein, a rail analyst with Value Line, an investment and research advisory service. ''The railroads should be strong in the 1980s.''