Police are allowing displaced Whaley Bridge residents affected by the incident at Toddbrook Reservoir to briefly access their homes - but under controlled conditions and only for a brief period of 15 minutes.
Over 1,000 residents were evacuated from the area on Thursday due to the "substantial threat to life" posed by the damaged wall of the 180-year-old reservoir.
Derbyshire police have said residents could be away from their homes "for several days", but announced on Friday that it would be allowing one person from each household to access their property to collect any essential items and family pets.
This would be carried out under "controlled conditions" for a brief period of 15 minutes.
In a statement yesterday (Friday), it said: "We understand that people have had to leave in a very short period of time and that in doing so they may have left vital items, and family pets, in their properties.
"Residents are now able to return home for a brief period of time. One person from each property will be able to attend any of the road blocks into Whaley Bridge and speak to officers where they will be signed in and out.
"Emergency contact details will be taken, along with the address that they will be attending. That person will be able to access the property and will be given 15 minutes to do so. That person should then exit via the same route they entered."
The force said any residents re-entering Whaley Bridge would be doing so at their own risk - and that the risk to life remained high in the area.
And it added: "Should the dam fail, or there be a fear that a collapse is imminent, the emergency service vehicles will sound their horns three times and a loud hailer will also sound.
"Residents should leave the area immediately away from the dam wall and to higher ground.
"Residents are warned that the current situation regarding the period of time in which they will be away from their homes could be several days and that they should consider this when they are returning to their properties for essential items."
Police warned there could be queues at the roadblocks, and asked for patience so officers could "allow people into the area in the safest manner possible".
Anyone who could delay returning to their property was asked to do so.
Speaking at a press conference on Friday, Kem Mehmet, Assistant Chief Constable of Derbyshire Constabulary, said: "I must stress that the structural integrity of the dam wall is still at a critical level and there is still a substantial threat to life should the dam wall fail."
He said asking people to leave their homes had been "a really difficult decision", especially in relation to animal welfare, and praised the residents for their support.