The River Thames at Reading has recorded its lowest level on record.Firefighters responded to 393 wildfires across England and Wales in July, making it the busiest month on record.For the first time in their history, Hungary and Romania had to shut down atomic reactors normally cooled by the Danube.The largest nuclear power plant in Hungary, the 44-year-old Paks, had been producing at one point only 240 megawatts of power rather than the usual 2,000.Hungarian authorities have asked citizens to reduce energy use in the peak evening hours.In Romania, the Danube's water flow fell to 1,500 cubic metres per second, less than a third of its July average, according to the National Institute of Hydrology.Authorities have already shut down one reactor unit at the Cernavoda plant for safety reasons, which provides about 20 per cent of the country's power.Acting Prime Minister Ilie Bolojan also appealed to citizens to voluntarily limit electricity usage in peak evening hours Romanian authorities even needed to conduct a controlled explosion in the river to direct cooling water to its sole operational nuclear plant.Two car plants in Romania run by Dacia and Ford have agreed to halt production for more than a fortnight to reduce electricity consumption.In Serbia, record-low Danube levels have pushed the country's key hydro-electric plant to operate with only 20 per cent of its capacity.Water levels are not expected to rise on the Danube in the coming days or even weeks as no significant rainfall is forecast.ABC with wires