sides collapsed need help

[Jojo.b]

Soil type?
depth of pond?
more pictures
. with out these you could simply fold back the liner and pull out the collapsed soil . that is if you have enough liner to fill that void if not one way to do it would be to fill the pond slowly and at the same time fill in your sides with dirt compacting as you go against the underlayment .

Sorted it and saved everything thanks

 

[GBBUDD]

If you post some good photos we may be able to help this from happening again to you.

 

[Cromwell]

I think the soil under the liner has collapsed as well

Same happened to me. Tried hard to have a frame made to hold loose earth walls from falling as water levels sink. So took out the lot.Filled in 5 feet deep 30 foot long 7 feet wide pond and will set it all as a stream without walls at 3 feet deep and help down by rocks and gravel . At end will dig a 4 feet deep tank 7 foot wide and sq .Therefore my water lily will survive well while im taking my time getting my stream right .Ill brick wall the tank and use liner in it. Once set up can set header tank at top and used bottom tank with lily and water pump to pipe it up to header so always have enough water

 

[j.w]

@Cromwell