The main Chinese contractor on the extended Nairobi-Naivasha Standard Gauge Railway (SGR) insists that construction work is on schedule, and expects the longest rail tunnel on the line to be completed this month.

According to a spokesman for China Communications Construction Company (CCCC), the laying of tracks and rail sleepers is well underway, with the line being placed from the Rift Valley county of Narok running toward the capital of Nairobi.

Steve Zhao, the CCCC Kenya SGR project spokesman, told local media that the company is on course to complete the 4.5 kilometre Ngong tunnel in August. This project will ultimately produce the longest railway tunnel in the country.

Around 6% of the railway line will consist of three tunnels measuring 7.2 kilometres. It will also have 27 bridges measuring a total of 17.3 kilometres.

The 120 kilometre Nairobi-Naivasha line is the first of the three segments that make up the second phase of the SGR project, which ends in Malaba on the Kenya-Uganda border. Five new stations will be constructed along the line.

Besides the Ngong tunnel, two more tunnels measuring 2.64 kilometres have already been constructed. The Nairobi-Naivasha SGR project is expected to be completed by June 2019.

Some analysys anticipate the Nairobi-Naivasha SGR project to bolster economic growth along its route, and a special economic zone (SEZ) in the Mai Mahiu/Suswa region is being set up.

CCCC is involved in many Belt & Road projects, and in April was included in the CES Belt and Road Index, launched by Hong Kong Exchanges and Clearing Limited, the Shanghai Stock Exchange and the Shenzhen Stock Exchange.

Other traditional energy and infrastructural enterprises included in the index are: China National Petroleum Corporation (CNPC), Sinopec, China State Construction Engineering Corporation (CSCEC), and CRRC Corporation Limited (known as CRRC).The index will evaluate its constituents every year, and help investors get exposure to Belt & Road related activity.