On Friday, 9 October, the maintenance dredging works were completed in Rukki kanal, a channel on the Rohuküla-Heltermaa fairway between mainland Estonia and Hiiumaa Island. As a result, a depth of 5.2 metres according to the EH2000 height system is ensured. The works were ordered by the Estonian Maritime Administration and performed by Insenerehituse AS.
The MA regularly performs hydrographic surveys in the channel because the depths in the channel are constantly changing due to accumulation of sediments caused by both natural phenomena such as storms, and the movement of ships in the channel. The latest survey before the maintenance dredging took place on 22 April this year, which revealed that the minimum depth in the channel was 4.8 metres. In case of low sea level the traffic of passenger ferries in the area may be hampered, so the costs of maintenance dredging of Rukki kanal are included in the calculations of the state fiscal strategy until 2023.
In order to avoid interrupting vessel traffic between the mainland and Hiiumaa, the maintenance dredging works were carried out in night time, starting after the departure of the last passenger ferry in the evening and finishing before the first departure in the morning. According to the head of MA Waterways Department, Mr Kert Süsmalainen, everything went smoothly as expected. Autumnal weather had to be considered, but all works were completed on time. Earlier, the dredging works were performed using bucket dredgers, but this time a suction dredger was used, making the operation quicker and considerably cheaper – in 2018, maintenance dredging of Rukki kanal cost 650,000 euros (VAT excluded), while this year the cost of the dredging works was 379,000 euros (VAT excluded).
Rukki kanal is 2.5 km long, 60 m wide and 5.2 m deep (EH2000). The MA has published a navigational chart correction and the results of the hydrographic survey works are also available in the application Nutimeri.