Import tax overhaul bill coming, would help U.S. seaports WASHINGTON (Reuters) - A U.S. import tax collected only at shipping ports would be converted into a fee on goods brought into the United States by rail and highway from Canada and Mexico under legislation expected to be introduced next month in the U.S. Senate. The two senators from Washington State said on Thursday that they will offer the bill to repeal the harbor maintenance tax and impose a new road-and-rail import tax, a move that would benefit seaports such as Seattle and Tacoma in their state. The overhaul proposed by senators Patty Murray and Maria Cantwell, both Democrats, would prevent businesses from dodging the harbor maintenance tax by unloading goods at a Canadian or Mexican port and then shipping the products into the United States by road or rail, Murray said on Thursday. "This legislation will change the harbor maintenance tax to give shippers new incentives to move their goods through American ports - particularly those in the Pacific Northwest," Murray said in a statement. The harbor maintenance tax collects $1.25 per $1,000 of cargo value. It raised $1.6 billion in fiscal 2012. The revenues flow into a trust fund that is presently in surplus. Murray and Cantwell want to scrap the harbor maintenance tax and do away with existing limits on how the fund's capital can be spent to take in a wider variety of harbor projects. Similar bills for harbor maintenance fund reforms have been introduced in the Senate and the House of Representatives, but they all face long odds in becoming law, given the failure of previous measures and Congress' fiscal deadlock, analysts said. While Cantwell and Murray are eager to protect Washington State ports from rivals in nearby British Columbia, their legislation would help U.S. ports nationwide, said Paul Bea an analyst with Ferguson Group LLC, a consultancy. Dredging companies have lobbied for more harbor project spending, Bea said. For instance, Orion Marine Group Inc (ORN.N) and Great Lakes Dredge & Dock Corp (GLDD.O) favor more harbor maintenance funding, according to their 2013 financial statements. Editing by Kevin Drawbaugh and Andre Grenon