‘I hope so,’ said Fountain. ‘I felt the tremor right through me when the pipes opened. Aye, it’s no exaggeration to say the ground quivered. It’s like we’ve woken a sleeping giant and he’s about to come at us from out the wrong side of the bed.’

Gunson hid his surprise. Stephen Fountain was not ordinarily given to such flights of fancy.

‘I am taking your concerns seriously,’ he returned. ‘Please do not think otherwise.’

Craven was getting impatient. ‘It’s a wild night, all right, but this,’ he kicked at the embankment, ‘will withstand anything the elements can throw at it, and that includes the pipes being fully opened. This dam’s five hundred feet thick and there’s bound to be some settlement. There’ll be more over the coming weeks, mark my words. Are we to come out in the dead of night to record every bit of it?’

Gunson pulled his collar up and set off to climb higher. ‘Let’s look at the water.’

He was the first to gain the flat path on the top of the embankment and a rising uneasiness made his heart flutter as he did so. Angry waves tossed spray up to his knees. The reservoir the dam held at bay surged restlessly.

Gunson waited for Craven and Fountain to reach him.

‘I was here late this afternoon,’ he shouted above the wind, ‘and it’s fuller now. It should have dropped since the pipes were opened. Has anybody checked the weir?’

He didn’t wait for an answer, but turned and, braced against the wind, led the way across the top of the embankment towards the overspill. The weir was dry, the river a faint glitter at the foot of it.

‘Look at that! Not a trickle! The reservoir’s not even at capacity,’ said Craven. ‘I’m telling you, there’s nothing to worry about.’

Fountain shook his head in exasperation and appealed to Gunson. ‘You’ve just seen with your own eyes that opening the pipes has made no difference whatsoever.’ He turned to Craven. ‘If we don’t relieve the dam somehow there’ll be a blow up, I’m telling you. There’s three million tons of water held up here that’ll smash this embankment to pieces. And us loitering here like we’re debating the price of milk in a coffeehouse!’

‘You can’t know—’

Fountain cut him off. ‘What I do know, David Craven, while we’re up here debating the issue, is that a shitload of water once released will go where it bloody well wants!’

‘Gentlemen,’ said Gunson, glancing at Fountain’s clenched fists. He’d had an idea, and hoped he could express it before the two men came to blows. ‘Water will go where it can. Let us take a further precaution and supply another option.’

He looked into the faces of the other men.

‘Blow up the weir?’ said Fountain.

Craven shrugged. ‘We built in the capacity for it, but I don’t think it’s necessary. Wait a while, at least.’

‘Yes, I understand your reluctance,’ said Gunson. ‘This may be an unnecessary step, but is it one we can take without damaging the integrity of the reservoir or delaying its commissioning, yes?’