It was a week yesterday since the nine puppies, then 5 weeks old, were left in the bin near the boat ramp at the Clyde end of the lake in what Mrs Saunders called an act of "unbelievable cruelty".
The puppies, thought to be Staffordshire bull terrier or mastiff-cross, were left to die by "starvation, dehydration or cooking in the heat", she said.
She said it was "quite a thorough process" as the SPCA would consider the applications then inspect the homes to make sure they were up to standard and suitable for a dog.
It will still be "quite a few weeks" before the puppies could be re-homed as they still were not old enough to be vaccinated, microchipped and neutered, all of which would be done at a cost of $535 to the SPCA.
Mrs Saunders said one Hawea man had even offered reward money to help find whoever had left the puppies in the bin.
However, she said the SPCA was following strong leads and the man had donated the money instead.
She said one puppy had been a little unwell but had been seen by the vet and the rest were doing well.