ANKENY, Iowa — Time is taking its toll on U.S. railroad bridges and trestles – some of which are more than a century old – and causing an urgent need for costly refurbishment or replacement.

Norfolk Southern (NS) Railway recently announced the company is “pursuing projects” involving the replacement or refurbishment of rail bridges due to decades of service supporting heavy coal and grain cars, extreme temperatures and other factors. Other Class 1 railroad companies are following suit.

“Approximately 100 bridge projects in the rehab or construction phase are going on,” Jim Carter, NS chief engineer of bridges and structures, told news sources.

NS inspects all of their bridges on an annual basis and is currently focusing on replacing timber trestles with ballast deck precast, pre-stressed concrete and box girders mounted on pipe pile filled and capped with concrete, Carter told Progressive Railroading in October.

It is tough to identify how many rail bridges across the U.S. are in need of replacing or major overhauls, though each respective Class 1 railroad maintains its own inventory and repairs them as circumstances demand.

Unlike the nation’s taxpayer-supported highway system, rail bridges and tunnels are privately owned by the rail companies, explained Mike Steenhoek, executive director of the Iowa-based Soy Transportation Coalition (STC), meaning only the rail companies know exactly how many bridges are obsolete.

“Since our nation’s rail infrastructure is privately owned and maintained, it is imperative that we preserve an environment conducive to continued investment by the rail industry,” Steenhoek told Farm World. “Given the increased productivity of the American farmer and the increased demand for U.S. agricultural products among our international customers, more and more is expected of our rural transportation system - particularly roads and bridges.”

The STC and other ag transportation watchdog groups understand that costs incurred by railroads for upgrading or replacing infrastructure are passed on to rail shippers and customers in the form of higher fees.

Making sure that the fees passed on to customers are not unrealistic is the purpose of the STC.

“In certain areas of rural America, grain and oilseed shippers can encounter exorbitant rail rates that, most routinely, are passed onto farmers in the form of lower bids,” said Steenhoek.

“In such cases, agricultural shippers must have a process available to them to seek relief from practices that are adversely affecting their operations.”

The Surface Transportation Board (STB) made it easier for rail customers to file a rate or unreasonable practice complaint against rail companies by recently lowering the filing fee from a prohibitive $20,000 to $350.

But with rail companies facing imperative major infrastructure upgrades along with the expense of replacing or upgrading technology and equipment, it may be tough to get the three-member STB to side with rail shippers and customers often.

Burlington Northern Santa Fe (BNSF) Railway announced that flood and weather-related calamities this year will cost them an extra $375 million for repairs to track and other infrastructure.

The disclosure came in a Sept. 27 letter from BNSF chairman and CEO Matt Rose to the STB in response to the Board’s request that BNSF detail how its company plans to manage service demands in the coming months.

According to Rose, BNSF’s two busiest corridors were temporarily taken out of service due to flooding, including the Twin Cities-Seattle mainline near Minot, South Dakota, and a subdivision line between Lincoln, Nebraska and Kansas City, Missouri near St. Joseph, Mo., earlier this year.

“We undertook extensive rebuilding and hardening efforts, including raising miles of track by up to eight feet, building levees and berms to protect the rail, and repairing and replacing many miles of damaged track, bridges and structures,” Rose informed the STB.

BNSF will invest $3.8 billion in capital spending in 2011, according to Rose. The company will install 3.3 million railroad ties— an all-time high for a single year— while investing millions more on locomotives, freight cars, equipment and technology, respectively.y.

“We (have) continued to make investments in our railroad despite decreased volumes over the past four years,” Rose told the STB.

A rail bridge taken out of service can be a crippling blow to the transportation of agricultural products, according to the Illinois Soybean Assoc. (ISA), which recently conducted its own study of dilapidated and obsolete bridges across the state.

“Pinch points (bridges) could be like the venturi of the hour glass – the narrow spot,” said Scott Sigman, a transportation and export infrastructure consultant with the ISA. “If it breaks, nothing is flowing or it all flows out and its a mess. On the other hand, when it’s flowing normally, it’s like fluid. The goods go where they need to go.”