Editor's Note: The following piece was written by HRW-Hydro Review Worldwide chief editor David Appleyard, who recently attended the Renewable Energy World Conference & Exhibition. REW Europe was held earlier this month in Vienna, which has been affected by the recent floods in central Europe. This piece previously appeared on HydroWorld.com's sister site, RenewableEnergyWorld.com.
There was an extra level of excitement and anticipation at the Renewable Energy World Europe and Power-Gen Europe Conference and Exhibition in Vienna last week. Not just because more than 13,000 of the world’s renewable energy and power industry had gathered to hear the latest developments and to see top power leaders debate Europe’s energy future, but also because the swollen Danube runs just a few hundred metres from the convention centre of this beautiful, historic city.
Putting this into perspective, through the city the typical flow of the famously blue — though rather murky, brown and uninviting when I happened to catch a glimpse -- river is typically some 2000 cubic metres per second. Around the middle of last week, when waters peaked there and the conference was -- figuratively speaking -- in full flow, the flow of the nearby river was estimated at 10,000-11,000 cubic metres per second. Although, as one local delegate assured me, this is well within the safety margin of the city’s flood defence measures, some 14,000 cubic metres per second, there are many, many others in Central Europe who are far less lucky.
Huge floods have swept through the Czech Republic, Austria, Hungary and Germany over the past week or so and the crisis is deepening. Around 15,000 people in the northern Saxony-Anhalt region of Germany have been told to evacuate after a dam near Magdeburg reportedly failed and at least a dozen people are known to have died already, including two tragic fatalities in our host country Austria.
With the horrific flooding spreading along the paths of the Elbe, Danube, and Vltava -- and water levels not seen since the 15th Century in some regions -- the power of the Europe’s rivers in full spate in there for all to see. For example, the Elbe River in Magdeburg reached nearly 7.4 meters, compared with a more typical level of around 2 metres.
Perhaps even more striking is that these latest floods come only about a decade after the last set of catastrophic floods to impact on this region which hit in 2002 and followed a similar event in 1997.
Indeed, the water level in Magdeburg last week was apparently higher than during the reportedly 'once-a-century' floods of 2002.
Almost coincidentally, the role of hydropower in flood projection and flow management was further highlighted at the Renewable Energy World Europe event with a technical tour to the Gabcíkovo waterworks system in Slovakia.
Owned and operated by Enel subsidiary Slovenské Elektrárne a.s., Gabcíkovo was originally conceived as the Waterworks System Gabcíkovo-Nagymaros -- a common investment between Czechoslovakia and Hungary.
A 1977 contract between Hungary and Czechoslovakia concerned the construction and operation of the Gabcíkovo-Nagymaros works which were designed with a number of goals in mind, including power generation, supporting shipping navigation and flood prevention on the Danube in an area between Slovak capital Bratislava and Hungary’s capital city Budapešt.
However, at around the time of their split from the communist system, Hungary decided not to pursue their part of the development. After withdrawal of Hungary in 1989, Slovakia completed an amended design for the Gabcíkovo stage, though it still serves in a number of roles, including flood protection on the Danube from Bratislava to Štúrovo in Slovakia, transportation services and electricity generation with more than 720 MW of installed capacity.
As initially conceived the project would support water levels associated with a 1000-year flood, some 14,000 cubic metres per second.
With the flooding in Central Europe, hydropower development and its role in managing water flows has again been pushed to the top of the political agenda, not least as a result of the huge costs associated with such a catastrophic event. For example, Germany’s Chancellor Angela Merkel has already pledged EUR100 million in emergency funding to support flood affected areas and a crisis meeting is expected between the various Central European governments with a view to addressing who will pay for the clean-up costs, estimated at many billions of Euro.
Perhaps more important are the design parameters that hydropower and flow control systems are required to meet in the face of a changing world. The increasing frequency and severity of such events raises a number of critical questions which the politicians must address, the affected people must allow and pay for and hydro engineers must design for.