A photo tour of downtown Sydney following the big rain storm of 10 Oct 2016.

I don't recall that this storm was supposed to be a big event.

Though maybe I should have listened to Frankie!

This was just an off-shoot of Hurricane Mathew, which had already steered east into the Atlantic far to the south of us.

While it was raining heavily, there was almost no wind. Just a persistent heavy downpour.

Environment Canada is now saying that yesterday's storm dropped a new Sydney record of 225 mm (~8 inches) of rain in a single day - and most of that over a 6-hour period. My first realization that this was much more precipitation that usual happened mid-afternoon, when I noticed that the Wentworth Park pond had overflowed its banks. This isn't unheard of, but the water level was higher than I had ever seen if before. So I walked down to the park and captured this video:

It wasn't until some time later that I realized Sydney - and indeed the whole region - was being inundated. This picture, by Robert Boutilier, of the normally-sleepy Wash Brook where is crosses Whitney Avenue is what woke me up to the crisis unfolding here. 

Towards evening the rain fell off, but the wind picked-up. It was howling out there for several hours.

This morning I set out to follow the path of the Wash Brook, from below these falls, to the newly-built flood channels at Open Hearth Park where the Wash Brook empties into Sydney Harbour.

Map to show the path I walked this morning and the approximate locations of the photos that follow.

01 - Large tree down at Wentworth Park

I'm guessing that the soil was so wet here, that it was unable to support the tree when the wind came up.

02 - A pair of large shade trees down in Wentworth Park

I was really saddened to see these two down as they formed a lovely shaded spot for sitting by the pond in the summer.

03 - Another big park tree goes down

This one is so big I had a hard time capturing the whole of it in a photo. It is 2 trees down from the place where that tree-climbing dog does his thing. Not the monster tree with the huge wide trunk, thank goodness. She still stands.

04 - Tree down on Lorway Avenue

This one seems to have stopped short of crushing the truck. I am not sure what, if anything, is holding it up. Note the power lines stretched tight.

05 - The Wash Brook where it crosses Park Street

This is looking upstream towards Whitney Avenue where the waterfall had been.

06 - Wash Brook looking downstream from Park Street

Same location (almost) as the last picture, but looking the other direction.

07 - Wash Brook just below Whitney Avenue

This would have been the foot of that waterfall yesterday.

08 - Tree leaning on house on Brookland Street

09 - Looking upsteam at the Wash Brook where it crosses Union Street

10 - MacKenzie Street is still flooded from a still-overflowing Wash Brook.

11 - Where the Wash Brook crosses Brookland Street

The Wash Brook turns north just before this bridge. This is a choke point for the brook. It often gets backed-up right here. In part, this is because the brook channel narrows to go through short tunnel, and also because the flooding brook carries a lot of yard debris to the tunnel where it gets caught (you can see a bunch of that debris in this picture). 

12 - Morrison Street looking north towards Townsend Street

The Wash Brook runs parallel to this street, running just behind this building on the right.

13 - Trees and hydro wires down on Brookland Street

14 - Looking south (upstream) at the Wash Brook from Townsend Street

This must be another choke point - and a low point on Townsend Street - because it is one of the first places to accumulate water when the Wash Brook starts flooding.

15 - Railway trestle that crosses the Wash Brook near Prince Street

This short bridge was identified as a significant choke point for the Wash Brook during the Tar Ponds MOU. I'm not sure why it wasn't replaced. Probably jurisdictional issues. Note the Sobeys store nearby.

16 - Railway trestle again from a different angle

Note that the narrow-channel of the Wash Brook does an S-turn through the bridge and that the bridge is especially low. If some sort of debris gets caught here (and it often does), the water will back-up to Townsend Street and then to Brookland Avenue very quickly.

17 - The Wash Brook enters Open Heath Park at Prince Street

The water that makes it here is usually home free. The brook widens into an engineered channel and heads due north to the harbour. If I remember correctly, these channels were designed to handle 50-year storms - which is to say the assumed runoff from the largest storm in a 50-year period. Yesterday's storm was clearly larger than the assumed 50-year storm because the water level on Prince Street where this picture was taken was under at least a foot of water yesterday (about the level of the top of that concrete railway bridge). I didn't see it myself, but I did see video from a car passing through it.

18 - The engineered channel at Open Hearth Park carries water to Sydney Harbour

The green-space of Open Hearth Park forms a flood plain for the channel. I am pretty sure this whole scene would have been under water yesterday afternoon/evening. To be fair, I did notice that the harbour waters were at least a meter higher than than usual because of (I would guess) a storm surge - and so there was less of a drainage gradient than usual. But this feature of the park does seem to have worked very well. Any water that was on the floodplain has drained back into the channel overnight - and the water from the Wash Brook that made it this far seems to be flowing smoothly to the harbour now.