An internal Finance Canada document raises questions about the Harper government's billion-dollar project to open up land-border crossings with the U.S.

The report says truck traffic has fallen sharply as Canada's manufacturing sector slumps, and wait times at key border points are negligible.

Altogether, the document drawn up by federal bureaucrats suggests a thinning border, not the thickening border federal politicians have been warning about since 2001, which has prompted massive investments in bridges, highways and customs plazas all along the U.S. border.

"Since the early 2000s, trucking traffic has declined in relative importance," says the report from last September, prepared for Deputy Finance Minister Paul Rochon.

"Canada's export mix to the U.S. is shifting away from manufactured goods, which tend to be transported by truck, towards natural resources, which tend to be transported by vessel and pipeline," says the report.

Not significant

"Border wait times for commercial traffic are not significant … long commercial wait times are infrequent."

The report notes that since 2001, exports to the U.S. have dropped to 76 per cent from 87 per cent of all Canadian exports, with China growing in importance as a major foreign customer.

CBC News obtained the document, with key sections censored, under the Access to Information Act.

"In 1994, almost two-thirds of Canadian trade to the U.S. was by truck," says a slide accompanying the report. "Since then, trucking's share has fallen to just 42 per cent, with trade by pipelines growing rapidly."

Says another slide: "Post 9/11 border thickening? But commercial wait times are not particularly high."

A spokesman for the Canadian Manufacturers and Exporters was quick to dismiss the contrarian report's findings, especially the data on wait times.

I think there are problems with the way they collect and analyze the data. - Matthew Wilson, exporters group

"I don't really believe the data that says wait times aren't really a problem," said vice-president Matthew Wilson. "I think there are problems with the way they collect and analyze the data."

Wilson acknowledged manufacturing trade is down, but said exports will eventually go back up, especially as the lower price of oil gives the sector a boost, and an open border will be critical.

"Volumes are going back up," he said. "The trade relationship with the U.S. is still our most important."

The purpose of the document is unclear. The first sentence in the section marked "Issue" is blacked out, as are other key parts of the analysis.

Update on trends

Asked why a report that raised doubts about border thickening was created, Finance spokesman David Barnabe said only that it "provided an update on recent trends in trade flows and border wait times."

"Border thickening and barriers to Canada-U.S. trade go beyond wait times," he said. "For example, firms must navigate border regulations and import reporting requirements, and face increased sensitivity to security threats."

Canadian exporters and others reject the claim that wait times are negligible at the Canada-U.S. border, saying the federal government does not collect the data properly. (CBC) The government is working closely with Washington on infrastructure investments, especially at high-volume crossings, and on streamlining paperwork and customs clearance, Barnabe said.

Since 2013, the Harper government has announced more than $1 billion in border infrastructure projects, including $470 million so far for a new bridge at Detroit-Windsor, included in the 2014 budget; $440 million announced last November for replacement of border structures across Canada; and other projects at Lacolle, Que. ($47 million), Lansdowne, Ont. ($60 million), Emerson, Man. ($10 million), and North Portal, Sask. ($10 million).

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