The popular pipe track trail through Kilsyth and Croydon will be closed until late next year for a water main project.
Riders on the 4.5-km section, which forms part of the Warburton to Carrum Trail, will be detoured through local streets.
The main detour for riders is between Hawthory Road and Norton Road.
The works are between Dunrossil Drive in Kilsyth and Yarraduct Place in Croydon South.
The pipes along the track are 80–100 years old, are leaking, and in need replacement.
Three existing mains, the M54, M55, and M56 are being replaced by two new 1350 mm pipelines to transport and distribute water between the Olinda and Mitcham Reservoirs.
While the works by Melbourne Water contractors will be mostly contained to the pipe track, the pipeline does cross underneath major roads and there may be impacts on traffic on Bayswater Road, Croydon South, Dorset Road, Croydon South, Mt Dandenong Road, Croydon and Hawthory Road, Kilsyth.
Once the new pipes are in place, Melbourne Water will reinstate any paths along the pipe track and revegetate the area.
Trees, which are not encouraged close to pipelines, will be removed for the project.
However, there will be replanting at a ratio of at least two trees for each one removed.