| Europe


Left: Beniarrs reservoir dam during drought in Spain


Below: Dovestone Reservoir in Lancashire, England


complicated climate”, led to 37% of availability of Spanish water resources. “So by constructing dams, we have obtained similar water availability that other countries in Europe have.” “We haven’t constructed dams because we love dams,” Granell added. “Of course I love dams because I am a dam designer,” he told a laughing audience, but explained that dams are a necessity to achieve water availability and regulation to standards like those found in the UK and other countries.


Maintaining its fleet of dams is one of the problems facing the Spanish industry. Although the annual cost of dam maintenance across the country has been estimated at €50m, in the past three years only €50m has been spent on this, and much less throughout earlier years. This is in sharp contrast to the €30bn dams contribute annually to the Spanish economy through power and agriculture etc. The majority of dams throughout Spain were built between 1950-80 and Granell said there has often been strong opposition to dam construction, generating controversy and social and economic problems over the years. And although Spain has been adapting to its problematic climate by using water flow regulation for many centuries now, Granell said with the impact of climate change, the situation is going to intensify. “Going forwards, to avoid or reduce social controversy about dam construction, there must be public participation and transparent decision making,” he concluded, adding that in the face of climate change, dams and hydraulic infrastructure must be resilient. “Dams must provide more flood protection with less risk. We must invest more than ever now in dam safety,” he urged.


Historical insight Darren Shaw, the Chair of the British Dam Society, gave


an interesting historical insight into the development of dams in his country. Explaining that the growth of British reservoirs was driven by the canal network around 1750-1800, it was the advent of steam in the 1800s which then reduced the need for canals, although many are still in use today. Throughout the 1800s, there was an increasing demand for industrial water to power industrial processes in factories and mines, and the exploitation of hydropower began. At same time it was acknowledged that clean water was essential for good health. Rapid urbanisation and pollution of rivers was leading to poor sanitation and illness and, as a result, many reservoirs and basic treatment works were constructed upstream


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to supply local populations. There was a boom in larger regional water storage reservoirs and stored volume increased dramatically. Following Second World War there also was a sustained period of hydroelectric power construction, mainly in Scotland, which continued into the mid to late1900s. According to Shaw, flood attenuation for downstream


populations was not often a formal consideration in dam design. However, in more recent decades there has been a focus on construction of flood storage type reservoirs which are usually empty and only impound at times of high river flow to reduce flood risk. Today there are over 3500 reservoirs in the UK, with the average age in excess 100 years. Between 1875 and 1925, there were over 300 deaths across the country due to the failure of reservoirs. This led to the introduction of the 1930 Reservoir Safety Provisions Act and since then, Shaw says there hasn’t been a single fatality in UK due to the uncontrolled release of water from a reservoir. Historically less attention was given to the


environmental impacts of dam construction, which led to major watercourse modification and alteration of habitats. However, in a lot of cases now, such reservoirs have become their own sites of special scientific interest and support protected species so, according to Shaw, removing them would cause environmental impacts. “Many of our older reservoirs were constructed when health and safety and maintenance given little consideration,” he went on to say. This often means valves cannot be accessed for replacement and tunnels


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