(Recasts, updates share price)
By Reinhard Becker
LEIPZIG, Germany, Feb 9 (Reuters) - Dredging the river Elbe in Hamburg to enable new generations of container ships to reach Germany's largest port can go ahead, the country's top administrative court ruled on Thursday.
Green pressure groups had lodged a legal complaint against the plan, arguing the environmental impact of dumping mud and sand on fragile coastal wetlands would be devastating.
Hamburg wants to make it easier for massive container ships to reach its port regardless of the tide to counter intense competition from Rotterdam, Antwerp and Bremerhaven.
Despite the river having been deepened six times already, some of the largest ships face a costly wait for high tides to dock in Hamburg and the city fears shipping lines will switch to other ports if the Elbe is not dredged further.
The court ruled that although parts of the planning process were incorrectly handled and broke planning law, this should not delay Hamburg getting consent to dredge the river.
However, it did say the authorities could improve their dredging plans to protect the environment, especially a type of marine plant which grows in the river.
Shares in Hamburg port terminal operating company HHLA fell 11.3 percent following the ruling.
The city of Hamburg and federal waterways authorities want to dredge about 130 kilometres of the river so that ships with 14.5 metres draught can reach the port, against 13.5 metres now.
Ships have grown from carrying 2,000 to 3,000 standard twenty foot cargo containers (TEU) in the 1980s to carrying up to 18,000 containers and vessels of 20,000 TEU are being built. (Writing by Paul Carrel and Michael Hogan; Editing by Maria Sheahan and Alexander Smith)