During the summer 2025 track closure, almost 3,000 piles, totaling approximately 41 kilometers, were installed in approximately three weeks on Espoo City Line Area Contract 3. The exceptionally tight schedule required precise advance planning and seamless coordination of pile production, transportation, and the construction site. The site has been selected as the Piling Site of the Year 2026, particularly due to careful foresight, efficient implementation, efficient logistics, safety, and close cooperation between the project parties.
The 2026 Piling Site has been selected for the Espoo city rail project's regional contract 3 between Koivuhovi and Espoo Centre. In the contract implemented by Destia Oy, the piling schedule, pile production, transportation and site logistics formed an entity in which a delay in even one part could have affected the progress of the entire work phase.
The Espoo city rail project extends from Leppävaara to Kauklahti. Area 3 is located between Koivuhovi and Espoo Centre. The contract includes approximately 4,5 kilometres of new double track, the construction or repair of nine bridges and approximately 40,700 square metres of pile slabs. During 2025, a total of approximately 69 kilometres of concrete piles were installed on the site. The implementation period of Area 3 is from March 2024 to August 2027.
Only about three weeks left for actual piling
The most demanding piling phase at the site occurred during the five-week rail outage from 23 June to 28 July 2025, of which approximately three weeks were spent on the actual piling. During this time, almost 3,000 piles were installed, or a total of approximately 41 pile kilometers. There were 2,150 concrete piles. Their lengths ranged from 6 meters to 30 meters, and almost every other pile consisted of two or more pile sections connected together. Destia Oy was responsible for the earthworks and foundation works, as well as the piling works. Due to the tight schedule, nine piling machines and six piling contractors were used in the piling.
The pile lengths could only be changed to a limited extent during the work, so the accuracy of the ground investigations and the reliability of the predicted pile lengths were crucial. Due to the high delivery speed, a significant part of the piles were manufactured in advance and their lengths were left with more margin than usual. This increased material waste compared to conventional implementation, but at the same time reduced the risk of piling being interrupted due to a lack of suitable pile lengths.
Approximately 480 pile loads to the right place at the right time
The scale of the piling was particularly evident in the site logistics. In 2025, approximately 480 truckloads of piles were delivered to the site. With nine piling machines working simultaneously in different parts of the site, the piles of the right length had to arrive at the right work site in the right order and at the right time.
The deliveries were coordinated by a person appointed to the task, who coordinated the required pile lengths and quantities, the needs of the piling machines and the progress of the construction site. An interim warehouse arranged near the construction site improved delivery reliability. The whole required continuous and up-to-date information flow between the construction site and HTM Yhtiöt Oy's Nummela pile factory.
Baseline studies guided the entire production chain
The ground investigations at the site not only provided initial design information, but their results also guided the production, transportation and installation of the piles. Since the piles were manufactured in large quantities in advance and their lengths could not be changed during the work in the usual way, the predicted pile lengths had to be as reliable as possible.
The pile lengths estimated based on the ground surveys affected the factory's manufacturing program, transportation, work station progress, and material waste management. The project concretely demonstrated that in a tight line closure, piling is not a separate work phase, but an entity formed by design, pile production, transportation, and installation, all parts of which must operate at the same pace.
The selection emphasized cooperation, safety, and the responsibility of young professionals.
The selection of the 2026 Piling Site focused on anticipation and planning of the piling work, efficient implementation within a tight schedule, and efficient logistics. The evaluation also highlighted the site's demanding operating environment, occupational safety, and cooperation between the various parties involved in the project. In addition, attention was paid to the active participation and responsibility of young experts in the implementation of the project.
The selection was made by the pile committee of the Finnish Concrete Industry Association, which consists of representatives of the concrete pile industry. The chairman of the pile committee was the chairman of the jury. Reijo Mustonen.
Project implementers
Builders: Finnish Transport Infrastructure Agency and the cities of Espoo and Kauniainen
Civil engineering and foundation contractor: Destia Oy
Piling contractor: Destia Oy
Designers: Ramboll Finland Oy and A-Insinöörit Oy
Pile supplier: HTM Group Ltd, Nummela pile factory
For more information:
Betoniteollisuus ry
Ari Mantila
ari.mantila@rt.fi