NEW YORK — Railroads large and small gave investors two consistent messages — economic growth will be slow but steady, and they will continue their commitment to investing in new projects such as freight corridors.

Intermodal projects continue to march forward on the state level as two Norfolk Southern Corp. projects are advancing and a new intermodal terminal has opened in North Dakota.

Trailer manufacturers say they are having problems finding enough tires to meet the surge in equipment orders, forcing them to take stiff price increases and offer customers less familiar tire brands.

Intermodal freight continued to surge during August, topping pre-recession levels and reaching the highest point this year, driven by a combination of domestic and international growth, experts said.

The Port of Los Angeles said it would delay enforcement of a ban on independent drayage operators despite a federal judge’s ruling upholding the legality of that ban as part of the port’s controversial clean-trucks plan.

Norfolk Southern Corp. said it completed a reconfigured rail junction in Northern Virginia, part of its “Crescent Corridor” aimed at boosting East Coast freight rail speeds.