Upgrade works worth $300m have begun for Highway 101 at Silicon Valley, California, in the US.

As part of the project, a 15-mile stretch is expected to be revamped for $24m in South San Jose, according to mercurynews.com.

The work is expected to involve replacing the top inches of the highway with rubberised asphalt to allow water to seep through the pavement.

The Tully road is also expected to undergo reconstruction worth $60m and will be due for completion in two years.

The project also includes rebuilding a road interchange and construction of an extra lane and converting an overcrossing into a new six-lane wide bridge.

In 2011, a project to widen lanes and add merging lanes for $103m is expected to be carried out.

Other project works involve building merging lanes and updating metre equipment for an additional $113m.

The project is expected to reduce congestion and clear potholes on the highway.