Railroads say they'll be ready: BNSF, UP optimistic about peak season despite tight capacity.(Union Pacific and Burlington Northern Santa Fe)

When California's heavy rains and mudslides closed three of Union Pacific's five rail lines from Los Angeles-Long Beach this month, intermodal shippers had a sinking feeling of deja vu. It appeared that the system delays that plagued them in 2004 were starting even earlier this year.

UP made a relatively quick recovery. It rerouted some of its cross-country cargoes along the Sunset route to Texas, which was not affected by the storms. UP said it planned to reopen the remaining routes on Jan. 24.

The service disruptions reminded shippers who depend on West Coast ports for their trade with Asia that the nation's intermodal network remains fragile. It also …