Humber River

[Chuck100]

I checked out the Don River immediately after the 175 mm thunderstorm in August. Probably not the smartest thing I could have done, but either way there was tons of carnage as well. That flooding was among the coolest thigns I have ever seen in my entire life. Too bad I didn't have my camera with me.

 

[dan e 1980]

it may be dangerous but it's pretty cool to look at.

 

[shawnmicallef]

We watched the don that night from the safety of the Gerrard st. bridge. cars stuck on bayview and the DVP surrounded by water. large trees being carried down river.

 

[Chuck100]

What was interesting about the flooding downtown was that the storm really only occured 15 km to the north. Not only that, it travelled east to west and didn't spend much time in the Don watershed. Imagine how much worse the flooding would have been if the storm travelled north to south and dumped all its rain in just one watershed.

 

[shawnmicallef]

All that paved watershed makes water travel fast.

 

[El Chico905]

The waterfalls that you see are a type of dam called a Weir. Most are left over from milling ponds that are created behind them. As far as navigation goes, these actually make it easier because without them on small rivers the flows tend to get very rocky and these allow a pooling effect that only requires one portage. Also these are know to be the most dangerous parts of the river where most drownings happen.
In a natural Hydraulic or "hole" the shape of the rock varies the suction and escape is posible. These man made weirs make perfect hydraulics where you might never come out. The weirs on the Grand river (esp. in Caledonia) are notorious for this.


I've never paddled the humber, but I have gone down the Credit and an unmarked breeched weir had created chute that I didn't see until to late, so I tried to run it and ended up broached on a rock at the top, so I dived out before she split all the way to the gunnels.

 

[dan e 1980]

everything seems to get stuck in whirlpool those things create. after the big august flood, i saw a bunch of fireman standing near one looking into the water, possibly looking for a body or bodies. do they have to make them soo tall though? can't they just terrace them in 1 foot drops? but then you probably don't get that water oxygenation thing happening.

 

[El Chico905]

I'm not sure about the modern ones, but the old mills need the drop for the power. There is a large one in streetsville that includes a terraced run for salmon.

 

[Chuck100]

The height and spacing depends entirely on the overall slope of the river. When the slope is shallow, the wiers can be far apart and still have short drops. When the slope is steep, the wiers can either be short but closely packed, or tall but farther apart.