The Halifax Regional Municipality is appealing a court decision about how to share the cost of repairing CN Rail bridges in the former City of Halifax.

The bridges need significant upgrades but the HRM insists it should only be responsible for the road on top.  

Halifax and CN Rail have argued for years about cost-sharing repairs to seven rail bridges in the south end of the city.  

Five years ago, weight restrictions were imposed on most of them, which are close to a 100 years old. The bill for upgrades could be millions of dollars.

Last fall, the Supreme Court of Nova Scotia ruled the city was responsible for both the pavement and the sub-surface section — right down to the concrete arch of the bridge.  

The ruling also says Halifax should co-ordinate the relocation of utility lines that run under the bridges.

But in December, the city filed an appeal. HRM lawyers say they have four grounds. Among them, they claim the judge misinterpreted the 2009 maintenance agreement between Halifax and CN Rail.  

The appeal will be heard the middle of September.

The timing means repairs to the bridges will be delayed again.

Meanwhile, after Halifax launched the appeal, CN Rail decided to withdraw its participation in another study.

The city wants to investigate the possibility of a commuter rail service. The $250,000 study is still in next year's budget. City officials say they'll try to do it without the rail company.