A Wobbegong shark which was found in the seawater intake tank of the Binngingup desalination plant last year will call permanently call the site home.
Water Corporation workers discovered the shark during maintenance on the plant last November.
The shark most likely swam into the tank through a 500m-long, 2m-diameter pipeline during its construction phase before there was a screen erected.
Despite seeking professional advice from shark experts, initial attempts to safely catch and release the shark were not successful and a follow up attempt earlier this year ended the same.
Corporation regional business manager Scott Moorhead said the shark had not been sighted for several months but visibility in that area of the plant is very limited.
``A decision has therefore been made not to continue these efforts,'' he said.
``It would not be possible for a similar shark to enter the station again via the pipe as the screen would now prevent this.''
The shark can not enter the main area of the desalination plant and water quality can not be compromised.