A $279,832 contract for preliminary design work on a tunnel in Provo Canyon was approved Thursday by a committee of the Central Utah Water Conservancy District.

A 5,000-foot-long tunnel is to replace a segment of the Olmstead Aqueduct that crosses a slide area and is occasionally damaged by landslides. The green pipeline runs the length of the canyon and was used by Utah Power & Light Co. to supply water to the Olmstead hydroelectric power plant at the mouth of the canyon until it was condemned in August 1987 by the Bureau of Reclamation for use in the Central Utah Project.Project Manager Michael J. Mick-elson, an engineer with CH2M Hill Inc., said a final design for the pipeline will be ready by July so the conservancy district can advertise for construction bids in August. Construction could then begin next November with the tunnel completed one year later.

Board member Nick Sefakis asked if the construction schedule could be expedited so the line could be in service earlier.

Mickelson said an accelerated schedule is possible, but the cost of the tunnel would likely be higher because contractors would have to submit bids based on preliminary design information instead of final design documents.