More than 700 people have spent a second night away from home as firefighters continued their battle to stop a dam bursting in South Yorkshire.
Crews from across England are using specialist pumps to drive down the water level at Ulley reservoir, near Rotherham.
If the dam's water level is reduced by 6ft (2m), engineers can start replacing the cracked dam wall.
Hundreds of people from nearby villages were evacuated to rest centres.
The situation was earlier described as "critical but stable", and South Yorkshire Police confirmed that the water level at the reservoir was falling.
Seventeen high volume pumps are removing four million litres of water per hour out of the reservoir overnight.
A section of the M1 motorway which has been closed all day remained shut overnight.
The spokeswoman said: "The situation will be reviewed once again tomorrow morning.
"Police are urging motorists to consider their journeys to work tomorrow."
On Tuesday evening people living in the village of Treeton were urged to leave their homes and a fleet of buses was sent in to take residents to rest centres.
Jamie Courtney, from South Yorkshire Fire service, said: "We have a real possibility of failure of the Ulley reservoir wall, the consequences of which would be widespread damage and flooding.
"This is precautionary measure for the public's safety and we would ask people to co-operate fully."