Climate change is associated with extreme weather conditions such as heat waves and droughts. Such events also have an impact on agriculture: the proliferation of droughts causes severe soil damage and crop failures. Against this backdrop, innovative solutions in support of the economical and efficient supply of water for the cultivation of arable land are being welcomed with open arms at a political level. The Ministry of the Environment, Nature and Transport of the State of North Rhine-Westphalia recently funded the "Bedburg-Pütz Irrigation Project" with up to 5.6 million euros. The sprinkler system featuring optimised irrigation management is intended to provide sufficient water for the fields, especially in dry summer periods, and thus ensure good harvests. Environmentally friendly installation as well as the durable and robust properties of the underground piping system are as essential to the overall concept as the irrigation technology itself. Hard-wearing PE 100-RC Line pressure pipes engineered by SIMONA were the natural choice. They were laid by IFK GmbH using the cost-effective and minimally invasive ploughing method.

Potatoes, carrots, onions and the like – even field vegetables tend to "feel the heat" in summer. What may seem innocuous actually turns out to be a significant threat to food cultivation. As a result of climate change, with ever warmer and longer-lasting hot spells, the soil is drying out and crops are facing the challenge of water shortage. As a consequence, harvests may be significantly impaired or crops may fail entirely. With this in mind, farmers from North Rhine-Westphalia have recently joined forces to form a public association aimed at implementing an efficient irrigation system for their fields, featuring optimised control and watering technology.

Comprehensive, cross-regional distribution of water
The project in Bedburg-Pütz represents a modern approach to climate change adaptation. Thanks to optimised irrigation management and improved distribution technology, the irrigation system supplies the fields in the Bedburg region with water throughout the year in a manner that is both economical and efficient. This also includes the area surrounding the Garzweiler open-pit lignite mine. In the context of open-pit mine dewatering, the groundwater was removed down to a depth of 260 metres by means of pumps. Irrigating the above-mentioned crops with the help of the public water network, availability of which remains limited, would be challenging and extremely expensive. With this in mind, the water needed for irrigation is to be pumped from the southern section of the 2,400-hectare association-managed area in Bedburg to the open-pit mine in the north via a network of water pipes spanning a length of approximately 20 kilometres. During dry periods, therefore, water supply is assured not only for crops grown in Bedburg but also for those cultivated in neighbouring areas. In addition, water distribution featuring optimised irrigation management offers a number of options for future expansion in support of climate-friendly regional supply. At the same time, it provides the basis for greater diversity with regard to cultivation, thus adding value for the farms and incentivising other downstream processing companies to settle in the region.

Durable pipe systems
In future, 2,500 hectares of arable land are to be irrigated with around 1.5 million cubic metres of water per year. For this purpose, the project includes the construction of six deep wells and a pipeline network spanning around 20 kilometres. The latter is made up of highly durable and robust PE 100-RC Line pressure pipes manufactured by SIMONA AG, one of Germany's leading producers of semi-finished thermoplastics and pipes. Durability is one of the key features of the single-layer pressure pipes made of extruded polyethylene. PE 100 pipes boast a service life of more than 100 years. Another benefit is their internal and external corrosion resistance, which ensures maintenance-free operation. The smooth internal pipe surfaces reduce pressure losses over the entire service life. In addition, the PE 100-RC pipes offer increased resistance to slow crack growth and high resistance to point loads. Thanks to their low weight, installation is simple, fast and cost-effective, even with long pipe lengths. Added to this is their high flexibility, which helps to prevent fractures of the pipe in the event of pressure surges or ground settlement. The polyethylene pipes comply with DIN 8074 in respect of dimensions and tolerances, in addition to meeting the quality requirements of DIN 8075. Last but not least, the polyethylene pipes are recyclable and thus resource-friendly, which further underlines the eco-friendly focus of the Bedburg-Pütz construction project.

Cost- and resource-friendly installation method
When it came to installing the pipes, the choice was made to lay them by means of the ploughing method. Salzburg-based IFK GmbH is a specialist in this field: cables and pipe systems are inserted directly into the ground using a plough. Applied since the 1960s in Germany, the method has been steadily refined and is particularly suitable for arable land and wetlands, along roads and paths as well as in forests and woodlands. The state-of-the-art ploughing method combines the benefits of outstanding environmental compatibility and superior cost-effectiveness. It is the perfect choice when it comes to laying long lengths of pipe in a short space of time – faster than with an excavator. In addition to reducing construction time and causing less disruption to traffic, this procedure also comes with a lower risk of accidents, is cable- and pipe-friendly, and usually allows the surrounding vegetation to recover quickly because of the "minimally invasive" (similar to a zip) displacement of soil. The cost savings, e.g. compared to construction with a trencher or excavator, are considerable.

The plough consists of a ploughshare, the laying box as well as a winch which is hooked up to a towing vehicle. At the starting point, the ploughshare is inserted into the ground – along the specified route – to the desired depth; in Bedburg-Pütz it was 1.7 metres deep. The towing vehicle pulls the pipe laying unit – together with the ploughshare and pipes – towards it by means of a winch. The ploughshare loosens up the ground as it is drawn forward, and the pipes are thus pulled into the ground. The soil then closes up over the pipe again and can also be compacted if necessary. In Bedburg-Pütz, several hundreds of metres of pipe were laid as welded sections. Since February 2023, eleven kilometres of water pipeline, featuring PE 100-RC Line pressure pipes, have already been laid for the eastbound line. A further nine kilometres of SIMONA pressure pipes for the westbound line are to follow in June 2023. They serve as water pipelines for the sprinkler systems. Construction work is scheduled for completion in August 2023.

State funding for lighthouse project
The rationale behind the irrigation of arable land for the purpose of ensuring the regional supply of the Ruhr region and the Rhine corridor – with up to 10 million consumers – is to guarantee the cultivation of food in the long term. With this in mind and given the choice of a state-of-the-art installation method and extremely durable and robust pipes, the Ministry of the Environment, Nature and Transport of the State of North Rhine-Westphalia rates the project as a so-called lighthouse project in the context of climate change adaptation and is funding the construction of the irrigation system with up to 5.6 million euros.

Bautafel
Construction project: Construction of three water pipelines for the Pütz-based irrigation association Client: Bewässerungsverband Pütz (Bedburg)
Building contractor: IFK Gesellschaft mbH, www.ifk.at
Planning and construction management: Rheinplan Ingenieurgesellschaft für Wasser- und Abwassertechnik mbH (Bonn)
Pipe system: SIMONA® PE 100-RC Line pressure pipes
Construction period: February 2023 - August 2023