Restoration of the shoreline-holding system
For the open beaches of South-East Baltic, groynes are currently the traditional shoreline-holding construction. In 2010 the Kaliningrad region government has adopted the target program “Baltic Sea, Curonian and Vistula lagoons coast protection for 2011 – 2020”. Within the program, the reconstruction of 5 km groynes efficiency in the three resort towns of Kaliningrad region was achieved. The best practice was implemented in Zelenogradsk (2016-2017), Pionerskiy (2018) and Svetlogorsk (2019-2020) towns.
Solution to which problem
The post-war concept of coastal protection on the Kaliningrad coast was focused on the creation of wave walls and promenades, which led to the loss of beaches in cities – federal resorts, although it solved the problem of further erosion and retreat of the coast. The shores abrasion aggravated by accidental conditions of hydraulic engineering installations led to the loss of an amount of recreational areas. Furthermore, the negative impact of storm events has been also increased last years. Reconstruction of shoreline-holding groynes promotes problem-solving, related to beach upset and the negative impact of storms.
Technical conditions
Before the practice implementation, the shore in the towns was in accidental conditions.
Implementation
The restoration was made by vibroimmersion of larch wooden piles and bunding of the root parts of groynes by stones with a diameter of more than 0.5 m. The length of the groynes was 50-60 m. The distance between the groynes is also 50-60 m, forming space between groynes, where a sandy beach was formed. During the construction the main problems were cramped conditions for working as there was no enough beach width and periodical storm event when the building halt was needed. This problems did not affect the costs but the duration of the construction - prolongation up to several months. Cramped conditions was almost up to the end of work, but in case where the more groynes were reconstructed, the work was going faster.
Result
Because of the reconstruction, the natural increase of beach width to 20-30% was observed. This also increased the attractiveness of the resorts for the tourism and the number of tourists has grown.