One year ago this weekend, the first vehicles started rolling over the N.W.T.'s Deh Cho Bridge across the Mackenzie River at Fort Providence. 

Commercial vehicles pay tolls every time they cross to the north side of the river, but so far the Department of Transportation says toll revenues from trucks travelling north is 17 per cent lower than expected.

"We are looking at a five year average. We'll need about five years of data before we know if our projections are accurate," said spokesman Earl Blacklock.

Trucks no longer get stuck waiting for the ferry but they pay almost $300 for large tractor trailers, about $75 for smaller trucks.

The government says it expected about $4 million to come in annually from bridge tolls. But several thousand fewer trucks have paid tolls than expected. That means revenues are about $700,000 short so far.

But Blacklock says those projections are based on the first fiscal year and timing could have affected the first 12 months.

"Truckers had plenty of warning there was going to be tolls on Dec. 1 and we suspect they did the natural thing to avoid the tolls by stocking ahead of time," he says.

Blacklock says the government expects numbers to even out as early as this winter as the diamond mines and North Slave communities restock. He also expects a boost when the territory's fourth diamond mine starts construction and needs to truck up materials. 

 "We think Gahcho Kue will definitely be a good addition to those numbers," he says.

The territorial government is paying for the bridge over 35 years. The toll revenue, along with the approximately $2 million that would have gone to the ferry and ice crossing, is supposed to keep the project cost-neutral. 

The government will be paying its bills to finance the project regardless of money from tolls, but the Finance Department says any shortfalls will mean less revenue for the territory.