A Shared Sustainable, Secure and Commended Supply
The region between the Main River and Rhön hills is one of the driest in Bavaria. So as to safeguard the drinking water supply for decades to come, a new shared water pipeline has been built using HFI-welded steel pipes from Mannesmann Line Pipe. There was even a very special commendation for this.
The dry periods on Franconia’s arid plain have become increasingly frequent in recent years, and climate change is expected to cause further extremes. This presents the municipal utilities with the challenge of safeguarding the supply of drinking water for a population of 220,000, agriculture, industry and commerce in the long term.
As a regionally involved project participant, Stadtwerke Schweinfurt utility company decided to secure supplies by adopting a cross-sectoral approach and aiming for climate neutrality. With their own ground-mounted photovoltaic system, they want to convert the entire energy supply for the water sector to green electricity in the medium term. Artificial intelligence is also being used to control the complex, cross-sector system and improve forecasts for consumption and generation.
26 km long shared water pipeline
So that sufficient drinking water capacity is available throughout the region, planning for an inter-municipal water supply system for Lower Franconia got underway in 2018.
In addition to Stadtwerke Schweinfurt, the parties involved in the implementation of the project were the special-purpose water supply association of the Rhön-Maintal Group, Stadtwerke Hassfurt utility company and the special-purpose water supply association of the Knetzgau-Sand-Wonfurt Group. A sustainable supply is assured by the ample water production capacities of Stadtwerke Schweinfurt, which will make 'exports' of over 1 million m3 of drinking water per year possible, even in the long term. The water is extracted from a total of 48 wells and distributed throughout the region via a 26 km long pipeline.
"Winning the Stadtwerke Award 2021 for our climate-friendly water supply strategy is a great vindication of our efforts in pushing ahead and effectively mastering the energy transition in our region."Thomas Kästner, Managing Director of Stadtwerke Schweinfurt GmbH
Persuasive consultancy services Stephan Maier and Kerstin Becker were the project managers from Mannesmann Line Pipe in charge of the engineering project. Maier re-calls: "At the bidding stage, we were fortunate to have the chance to present our expertise from numerous drinking water projects to the responsible parties on the client’s side and to share our positive experience in terms of duration, workload and costs of pipe-laying using the plowing method."
Also crucial for the award of the contract in addition to their technical expertise, however, were compliance with delivery deadlines, intelligent logistics services and the procurement of the required pipe elbows.
From May 2020, Mannesmann Line Pipe then supplied some 1,650 HFI-welded steel pipes in four different diameters from DN 200 to DN 400 in individual pipe lengths of up to 16 m. These were lined with Portland cement and externally coated with a 5 mm thick layer of PE. "We organized the deliveries as required to the storage locations we had previously assessed and found to be suitable," Maier explains.
Eco-friendly trenchless installation
To minimize the impact on the delicate ecosystems near the Main River, the pipeline was laid in the fall and winter of 2020/2021. Much of the route was laid using the plowing method recommended by Mannesmann Line Pipe. The Salzburg-based IFK company laid the pipe string 1.5 m deep in the ground and covered it directly with the loosened soil in the same operation.
Maier also continued to provide advice on site during pipe-laying. "Although we had to deal with contacts from four municipal utilities, four pipe-laying companies and a civil engineering firm, we literally pulled together from the outset and managed the project from design through to completion on time and on budget."
The outcome was appreciated not only on site. The jury for the Stadtwerke Award 2021 was also impressed by the new inter-municipal water supply system as part of the submission entitled 'Climate-neutral water supply in Mainfranken' and awarded them first place.
The prize-giving ceremony took place on September 7 and 8, 2021. Congratulations also from Mannesmann Line Pipe!
Pipe-laying with the plowing method
Using the plowing method, pipes with a diameter of DN 40 to DN 600 can be laid to a depth of 2.5 m in soil classes 2 to 5.
The advantages at a glance
- 20 times faster than a digger
- Up to 40% cheaper than conventional laying methods Protects the environment
- Reduces trenches, excavated soil, soil transport and land damage
- Minimal nuisance to neighbors