Battle looms over Shenzhen's plans to expand port

The competing needs of Hong Kong aviation, Shenzhen shipping and endangered pink dolphins are sowing the seeds of conflict between the neighbouring cities.

The growth of Shenzhen's western ports has long been limited by difficulties with the Tunggu Channel, a major access point to the ports since it was created in 2000. Shenzhen authorities originally asked for permission to route the channel through Hong Kong waters to allow access for bigger cargo ships. But the request was blocked on environmental grounds.

Now a new battleground is emerging as Shenzhen's plans to open up another channel clash with the expansion of Hong Kong's airport.

Shenzhen wants to make the Longgu West Channel, a fairway mostly for small and medium-sized ocean-going vessels, accessible to some of the world's biggest container ships. But that plan risks being scuppered by restrictions on the height of ships passing close to the future third runway at the airport. The height restrictions on waterways around the airport would, for the first time, stretch into mainland waters.

Hong Kong has dismissed Shenzhen's worries on the grounds that most of the ships using the channel fit beneath the 50-metre height limit. But Shenzhen has aspirations to dredge the channel to accommodate the mammoth container ships international companies are turning to as they seek to cut costs.

It puts Hong Kong and the mainland boomtown on a collision course, at a time when the two cities, despite their close ties, find themselves competing on several fronts, not least in the port business.