“Aqua Repono” – Latin for “water reservoir” – is the name of the project that will protect vines in the Traisental from drying out in the future. A kilometer-long pipeline will transport water from the Danube to the vineyards. Construction of the multi-million dollar project is scheduled to begin in late autumn and be completed in 2026. The aim is to “make better use of the available resources,” says winemaker Markus Huber, chairman of the Lower Traisental water cooperative.
“There are currently no free water reserves in the Traisental,” reports Huber, who runs the Reichersdorf organic winery in the municipality of Nußdorf ob der Traisen (St. Pölten-Land district). The situation is expected to worsen due to climate change. Higher temperatures mean that plants need more water. However, there is increasing heavy rainfall, i.e. a lot of rain in a short space of time, explains Michaela Griesser, deputy director of the Institute for Viticulture and Fruit Growing at the University of Natural Resources and Life Sciences (BOKU). Some of the water flows away because the soil cannot absorb it, making it more difficult to penetrate deeper layers. “Water is there randomly, not when you need it,” says Huber.
The aim of “Aqua Repono” is to keep water in the region in the long term and to enable local fruit and wine growing in the future. Around 200 hectares in the Traisental are to be irrigated. The area, where Riesling and Grüner Veltliner are mainly grown, is to be divided into sectors. Wells are to be set up in the area around the Danube. Water is to be brought from the Danube to the vineyards via a main pipeline around eight kilometers long and subsequent distribution pipelines. The vines are to be irrigated drip-by-drip via hoses. The pumps are to be powered by solar power.
The board of the cooperative will decide when to irrigate. Sensors will be used to determine whether drought stress is imminent. “The cycle will last ten days until the last vineyard is irrigated,” explains Huber.
The Lower Traisental Water Cooperative claims to be the largest irrigation cooperative in Austria with 181 members. After years of preparation, the contracts for the “giant project” will soon be awarded following a tender, says Huber. In order to lay the necessary pipes, roads will also have to be dug up. Investments in the high single-digit million range are planned for the LEADER project. 50 percent of the costs for the main pipe will be subsidized. The project has already been approved and an environmental impact assessment was not necessary.
Josef Glatt, director of the Austrian Winegrowers’ Association, estimates that around five to ten percent of the Austrian vineyard area is currently irrigated: “Due to the increasing drought, the demand for irrigation will naturally continue to rise.” The limiting factor is the availability of water.
Huber sees a competitive advantage: “In the long term, it will make a difference whether irrigation is possible or not,” says the 45-year-old, who is the tenth generation to run the winery. Irrigation in regions with little rainfall “makes sense,” also to ensure yield, says Griesser. It is important to use the measure in a targeted manner. Then the development of the grapes and the formation of the ingredients can be “optimally supported.”
“Due to their deep roots, grapevines can access water resources from deeper soil layers,” says Griesser. However, drought and heat put the plants under stress. This can affect the growth and vitality of the vine, the yield, the quality of the grapes and the taste of the wine. “Grapes can get sunburned, causing the berries to dry out,” explains Griesser. In persistent drought, vines close their stomata (stomata on leaves), but this increases the temperature on the leaf surface, which can lead to parts of the plant dying. “It is good for the vitality of the plant if it does not suffer,” emphasizes Huber. When stressed, more tannins are produced – too much of this is perceived as bitter when drinking.
“Aqua Repono” has already received an award – in the “Water” category, the Unteres Traisental water cooperative received the Energy Globe Austria 2023. The project has an additional benefit: in the event of a forest fire, the water from the pipes can be used to extinguish the fire.
2024-09-01 07:02:32