Vandals blocked a city sanitation line at the lagoon treatment system over the weekend, costing the city an estimated $50,000 or more to repair.

'This wasn't just some kids out up to some mischief,' said the city's director of operations, Brian Crist.

He said vandals broke through bars welded on and locked to the top of the manhole at the city's sewage treatment lagoon, which suggests there was more than one person participating.

The culprits then entered the five-metre deep hole, and further vandalized the stages city employees stand on when working on the pipe. This made room for the vandals to stuff the drainage pipe full of logs. The flow of treated sewage was blocked, causing it to rise up above the manhole, and flow down to the pothole lake along soil embankments, greatly eroding them in the process.

'Someone very purposefully went in to remove the top of the manhole,' said Crist. 'They had a very purposeful intent to sabotage the system.'

The incident took place sometime last Friday night or Saturday morning, before city inspectors noticed the damage, and called in crews to help repair the system, said Crist.

'The city of Whitehorse crew deserve mention, kudos to them for acting fast,' he said. 'This could have been a much greater disaster.'

The treated sewage did not leak from the drainage system, which flows downhill on a steep angle to the pothole lake, where the waste seeps through soil and into the Yukon River.

'This didn't have environmental ramifications.'

Human waste that is treated has already gone through numerous lagoons where it is broken down. It is not safe to drink at the treated stage, but it does not pose as much risk as does raw sewage, said Crist.

Though the situation could have turned worse, the costs to fix the damage are quite significant, especially with the incident coming days after city council learned it's facing a $304,000 deficit.

The projected $50,000 to fix the damage is a minimum, said Crist.

'If we were talking about going back, and filling in all the washed-away material, that would cost more.'

The idea now is to dig a swale, which involves laying geofabric cloth down and filling it with gravel to create an even slope down to the pothole lake, said Crist. The city has long-term plans to install a pipeline that flows right to the Yukon River, detouring pothole lake.

As it stands, the vandalism also caused huge amounts of excess material to wash down to pothole lake, along with the treated sewage.

'There are concerns we may not get efficient discharge this year, but that remains to be seen,' said Crist. That would mean the sewage would be effectively backed up for next year, putting more strain on the system.

As the sewage lagoon is a city-funded operation, the costs to fix the damage end up trickling down to residents, said Crist.

'Residents end up paying for this through their taxes.

'Who wants to see taxes raised or things cut out of the budget because of vandalism?'

Since the damage was an obvious act of vandalism conducted with intent, Crist added, the RCMP have become involved and have started an investigation. RCMP are asking anyone with relevant information to contact them at 667-5555, File #2007 94 66 77.