Ausgrid has responded to a resident's criticism of new signs on the banks of the Woronora River warning of dangerous power lines above.
The resident told the Leader the signs were unnecessary and created "an environmental mess".
"These signs must be expensive to install," the resident wrote. "It has taken three days with three workers".
"The signs warn sail boats that can clear two metre bridges at low tide that their masts will hit a wire.
"The depth of the river is so low you can walk across at low tide.
"In some cases, the signs are under wires ten metres high and not live."
An Ausgrid spokeswoman said safety was their "number one priority".
"Electricity cables and overhead line conductors can pose a hazard to vessels and people crossing navigable waters.
"Ausgrid recently completed a review of all water crossings on our network to ensure their ongoing safety and compliance with the NSW Maritime Electricity Industry Code "Crossings of NSW Navigable Waters" (c. 2009) in accordance with Australian Standards (AS 6947-2009).
"This review included risk assessing all crossings and where appropriate implementing safety control measures.
"On the Woronora River, this has required the replacement of some existing signs with larger bi-directional signs to ensure they are clearly visible and legible from a distance, in line with current safety standards."