May 29, 2013

Tracing Erosion of Stairs in Byrne Creek Ravine Park

I've been noticing active erosion along the stairs that go from Brynlor Drive into Byrne Creek Ravine Park the last several times that it has rained. Today I saw that the stairs are being undermined and eroded away in places, though just  a few days ago it appeared some repair work had been done to previous recent washouts on, and near, the stairs.

This has happened before, where (I think) Burnaby Parks repairs the stairs, but doesn't seem to locate and fix the source of the problem. I think that may be because pipes are Burnaby Engineering : -).

So today I backtracked the unusual flow to an area near where a storm-drain pipe had cracked a few years ago and had caused similar problems. This time I found water upwelling from a manhole cover on a storm-drain pipe in the same vicinity as the origin of the problem in the previous event. Water upwelling could mean various issues, but that's civic employee pay grade, not for a volunteer to guess at : - ). That upwelling was cutting a new channel down the steep ravine slope, hitting the stairs, and thereby channelling the flow along, and, under, the stairs.

I called the source of the flow in to Burnaby Dispatch, and within an hour they were on the scene and following up. Great response!

But I wonder why the initial problem was not detected before the first repair on the stairs. I hate to see my property tax dollars going to fix the same problem over again within days, without tracking or tackling the source. And, like I said, this happened before a few years ago, in almost the exact same way, with the source in almost the exact same place.

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Upwelling manhole

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Erosion where the unusual flow meets the stairs into the ravine

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Another view of the erosion

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A close-up shot of the steps being eroded

Posted by Paul at May 29, 2013 10:22 PM