TORONTO -- Canadian Pacific Railway Ltd. will acquire full ownership of a cross-border railway tunnel under the Detroit River through a US$312-million deal with OMERS Infrastructure.

CP Rail currently owns 16.5 per cent stake in the Detroit River Tunnel Partnership.

OMERS Infrastructure, an arm of the pension system for Ontario's municipal employees, first invested in the partnership in 2001.

The Calgary-based railway has operated the tunnel throughout the OMERS ownership period. CP Rail says full ownership of the tunnel will reduce its operating costs.

The 2.6-kilometre tunnel links Windsor, Ont., and Detroit and is an important transportation route between Canada and the United States.

The deal is expected to close at the end of the year, subject to regulatory approvals and other conditions.