New lower water tank secures the distribution of domestic water to the residents of Jakobstad

Pietarsaaren Vesi is developing its water supply network with a new lower water tank, which will more than double the volume of the domestic water lower water tank. Sweco was responsible for the implementation planning, construction and supervision of the new tank as a comprehensive service.

The operational reliability of the water supply network will improve in Jakobstad

Pietarsaaren Vesi will improve the operational reliability of its water supply network with a new lower water tank and pumping station, which will be completed next to the old lower water tank at the end of 2025. The investment, which is one of the largest in the history of the water utility, evens out fluctuations in water consumption.

“The volume of the domestic water lower water tank will increase from 1,500 cubic metres to about 4,000 cubic metres, which will increase the reliability of the water supply of 5,000 Jakobstad residents at different times of the day and in exceptional situations,” says Jussi Mäenpää, Head of Sweco’s Water Services Department.

Sweco was responsible for the implementation design of the lower water tank and the construction design of the inlet and departure lines for a distance of approximately 1.4 kilometres. The project included, among other things, area, geological, process and piping design, as well as structural and building services engineering. “We also carried out hydraulic modelling of the entire 210-kilometre-long water supply network,” Mäenpää adds.

The current lower water tank, which is in need of renovation, will be renovated when the new lower water tank is completed. According to Mäenpää, it was important for the new tank to fit in with the old one, and this was ensured by Sweco’s architects. “I think the new and old functionalist-style concrete tanks fit together nicely!”

Construction consultant ensured the quality of concrete castings

Sweco’s comprehensive role continued in the implementation phase with construction management and supervision. Sweco’s construction consultants put the contractors out to tender and then started to manage the implementation according to the client’s wishes.

“One of our most important tasks is quality assurance and, in particular, the quality assurance of concrete work,” says Matti Haajamo, Construction Manager at Sweco. Watertight concrete casting must be successful at once. “A single casting takes 28 hours, because it has to be done without interruption and slowly enough.”

Haajamo is very satisfied with the experience and expertise of the selected contractor. “The contractor’s own quality assurance has also been at an excellent level.”

Cooperation between the project parties has been effortless, and Mäenpää especially praises Pietarsaaren Vesi’s active approach and good interaction. “Plant investments of this size only happen once in most people’s careers, and it has been reflected in the good spirit and enthusiasm of the project.”

The lower water tank project has been a big part of the water utility’s everyday life for the past couple of years. “Sweco provided us with a professional, straightforward and committed partner for the duration of the project’s planning and construction,” says Glenn Lahtinen, Operations Manager at Jakobstad Water.