City should make Idlewild Dam report public
Perceptions by Gerry Warner
This week, thanks to a request I made to City staff, I obtained copies of the Idlewild Dam Breach Inundation Study prepared by Urban Systems for the City as well as a letter to the City from Sarah Crookshanks, senior regional dam safety officer.
I commend City staff for making these documents available to me because they are critical in understanding the work the City is carrying out now on Idlewild Dam which could result in the dam being in a reduced state of operations for two years or more and Idlewild Lake being lowered and possibly completely drained for the same period of time.
This, of course, would be a major loss of one of the City’s prize recreational assets for more than 50 years, a decision not to be made lightly. Were there other options? Unfortunately, we’ll never know because City Council chose to make the decision secretly in camera and not let Cranbrook residents and taxpayers in on the discussion.
Perhaps there was a good reason for councillors to have their initial discussion in camera until they understood all the implications of the engineering study and the safety officer’s letter. That way they could have prepared themselves for an informed discussion in public and a public vote. That’s good governance. Council could also have recommended both documents be made available to the public at City Hall so that taxpayers and residents could examine the documents themselves and raise questions they had at a future council meeting.
Instead of doing this, the City issued a press release saying Council made its in camera decision based on the “findings and recommendations” of the engineering study, but did not say what those findings and recommendations were. Now that I’ve had the opportunity to read the engineering report, I can tell you that one of its recommendations was for “information to be shared with the general public.”
So much for accountable municipal government!
Anyway, I’m no engineer, but I am a journalist with more than 30 years experience informing the public of what their politicians are doing – and not doing in many cases – and I’d like to inform you now of some of the key information I found in the documents.
The dam has a concrete, internal spillway without the capacity to handle the maximum flood possible referred to as an inflow design flood (IDF). This could lead to water spilling over the crest of the dam and eroding the downstream face of the structure leading to a complete dam failure and significant flooding in the city and possible loss of life. The report goes on to say: “The City should consider either increasing the spillway capacity to accommodate the IDF or armouring the downstream face of the dam to prevent erosion of the downstream embankment in the event that the dam is overtopped.” This would reduce the Dam Consequence Classification currently rated as “high” and “significantly reduce the probability of a dam breach due to overtopping,” the report says.
Whew! Do you really think this information shouldn’t be shared with you who live downstream of the Idlewild Dam? Are you satisfied with the dam danger being “significantly reduced” or should the whole damn dam be replaced?” Would it not be possible to simply increase the height of the dam and reduce the danger completely? Could an emergency ditch be constructed around the dam to reduce the flood danger like the diversion ditch the City constructed around the Phillips Reservoir? What are the cost numbers? Were other options considered? How long will we be without a lake?
These are only a few of the questions that occur to me and they may not even involve lowering the lake. I’m sure Cranbrook residents, being the intelligent people they are, could think of many more. Too bad Council doesn’t trust us to think for ourselves.
Given this, like me, make a modest suggestion. I suggest Cranbrook Council call a public meeting to receive input on whether the City should proceed on its current course regarding Idlewild Dam.
In my opinion, it’s the least Council should do.
Gerry Warner is a retired journalist and former councillor.