Jim Claydon, All Reservoirs Panel Engineer, was contacted with news that a dam may be in some danger of bursting.
'I was contacted on Monday, to check my availability, as it happened for a different dam.
I was available, and was not surprised to get a call at 5.30am on Tuesday, directing me to Ulley.
I set out immediately from Huddersfield.
With the travel chaos due to the floods, it took three hours to get to the site. It would have normally taken an hour.
As I was driving to the site, I was in touch with the contractor Paul Bentley, who had already been contacted by Rotherham. He and I suggested three 35-tonne excavators, one with a long reach and two with short reach, and 500 tonnes of fill to my spec.
This also added to the journey time, as I kept having to stop to take calls from him and Arup supervising engineer Dave Crook on site.
When I arrived, there was a large meeting going on, and as I entered the fire service chief was saying '. . . and we have one of the country's best dam engineers on hand'.
They all seemed delighted to see me and I practically had a standing ovation.
The picture was of erosion on the downstream face. The erosion had allowed some seepage through the embankment, and they had attempted to ll with sandbags, and had already started pumping to get the reservoir level down.
The hole then was 20m long and 6m high into the downstream side. There were three points of seepage, all carrying material down the slope. The seepage points could extend back into the embankment and cause it to fail.
We had two priorities: one, to reduce the water level; and two, to stabilise the face and put fill against it - not a plug but a stabilising weight on the embankment.
I was there then until midnight on Tuesday, and the Bentleys people worked until they ran out of fill. This was the period of most concern, as that night - Tuesday night/Wednesday morning - we had not achieved a great deal.
At 5.30am on Wednesday we installed more pumps.
There really was a risk of the dam failing that night. In the rst 36 hours, we had continuous surveillance, either myself, Dave Crook or Peter Kelham. I then did the shift until 18.30, after only three hours' sleep. I did manage to get a police escort there down the closed M1, which was completely deserted.
On the Wednesday, we were requested to go to the 'Gold' command centre in Shefeld to brief them on our progress. We were taken by the police and they hit a button marked 'The Full Monty' which put on the full sirens and lights. It was very exciting.
Friday we handed over to Rotherham Metropolitan Borough Council to monitor the embankment. There were two things to keep an eye out for: any outow of muddy water, which was unlikely; and the pumping. It had stopped on Thursday night but could need to start up again at any point. We also needed to make sure there were no problems caused to the spillway. But the rain will not damage anything now. We are putting all the technical issues into a report, which we will present to Rotherham council.'