Malcolm Snow wrote to Andrew Barr in August after concerns that new mooring and slipway fees would have an "adverse financial impact" on boat operators.

For years, the boat operators have paid nominal fees for these services which has helped make their businesses viable. However, with recent developments, including the Kingston Harbour and a new slipway, the boat operators are facing higher charges than ever.

Mr Snow said the ACT government fees, in particular for the slipway, would make the lake unviable for boat operators, of which there were now only three commercial enterprises on the lake.

"This will result in a reduction of operators on the lake, which the National Capital Authority believes would be a significant loss to Canberra's tourist industry," a spokeswoman for the National Capital Authority said.

Engineer and spokesman for a group of Lake Burley Griffin boaters, Brian Cropp, also addressed the issue with government.

"The slipway fees … are more than double of anywhere else in the country," Mr Cropp said in a letter.

He and a number of boat operators have also expressed concern over the design of the slipway after the state-of-the-art equipment was broken on its second use.

For the past two weeks it has been out of action in what is normally one of the busiest times of year for preparation.

Land Development Agency deputy director general of economic development Ben Ponton said a team of divers were required to put the cradle back on the rails, which was expected to cost about $10,000.

The specialist personnel are due to start work on the slipway on Wednesday.

"Any damage will be assessed when the cradle is placed back on the slip. A determination will then be made on what, if any, repairs are required and when the facility will be operational again."

Mr Ponton said the slipway had been designed and constructed to "rigorous" standards.

"The cause of the incident is being determined but initial investigations suggest that the incident was not due to a failure of the slipway," he said.

Mr Barr responded to NCA chief executive Malcolm Snow's letter saying the slipway fees did not include any recovery of the $3.4 million capital to construct the facility. He said the fees were a direct cost of the service.

"The building life cycle assessment of the Black Mountain Slipway identifies the required annual maintenance regime and associated operational costs of the slipway. The fees were designed for cost recovery purposes only, and the charge rate reflects the facility's use by the existing commercial operators."