The Phoenix Dam is so old it's no longer safe and is being decommissioned.
The man was arrested a short time later.
"When we find evidence of illegal fishing, we will hold people to account."
"Given the size and nature of supermarkets, rodents can enter and leave them from time to time."
A minimum level has been imposed to try and preserve some of the fish stocks, and farmers' irrigation is restricted to just 25 percent.
The store will reopen on Friday if all things go to plan.
"It is clear we have more work to do."
A second person is seriously injured.
Residents said it's a quiet neighbourhood with young families.