Careful of the ice in and around Calgary

[Sundancefisher]

I was going to set up a fishing trip for Sundance on Saturday but one of the lake staff was out walking on the lake and fell through the ice.

Given the average thickness is 8 inches and we have no Springs upwelling...this is a very strange thing. I need to think about what could cause it.

Anyways...everyone be safe this fine weather weekend!

Sun

[Geezle]

Something to do with the aeration maybe? :confused:

[goldscud]

There is no aeration going on....

[Badback]

The good news he wasn't injuried...I fished it last Sunday and was hoping for this weekend with some members of the forum...Well their is Chain, PCR and Crowsnest....

David

[oagie]

Interesting...

They had the machines on it last week clearing the ice for skating and setting up the lights...

I was hoping on fishing it tomorrow.

[DarkAisling]

This is really curious (and a real downer). I'm glad he wasn't hurt.

Has the ice been measured at the place where he went through?

[goldscud]

Couple of guys went through about 20 feet apart. Ice was rotten and only about 1" thick in those areas. He was breaking it with his arms when trying to get out.

[Sundancefisher]

POSSIBLE EXPLANATIONS FOR WEAK LAKE ICE

Generally in a natural lake pockets of weak or open ice can occur for the following reasons either on their own or in combination with other factors:

1. Really deep snow insulating the ice
2. Up welling springs or seeps
3. Rotting vegetation
4. Water currents
5. Debris on the surface
6. Man made wind mill or oxygenation system
7. Intentionally made hole from vandals or pranksters.
8. Pressure ridges from ice expansion and contraction.

RELEVANCE TO ABOVE POTENTIAL CAUSES RELATED TO LAKE SUNDANCE

Addressing the above in the context of our lake lead to the following speculation as we can not be 100% sure

1. While this problem is normally an early winter issue, snow is not that deep nor a real concern for this year. I drilled a number of holes last week. Ice thickness was greatest near shore…thinnest near the middle of the east side of the lake. Thicknesses were 11 inches to 7 inches. As such variability due to snow thickness should not have caused open water large enough to have 2 people fall in.

2. Up welling springs or seeps. As our lake is man-made this should never occur. However we do have the pumping system. There is a chance that warmer water may seep back into the lake. As the volume should not be substantial I can not see this being a factor this late into lake ice formation.

3. Rotting vegetation. When you see yellow or rotten ice on sloughs and pond and around the margins of lakes this is caused by decomposition of organic matter. Formation of methane gas from the anaerobic process that breaks down rotting vegetation rises to the surface and can pool in pockets. It is possible this impacted on ice formation. If this is occurring it could be a prelude to a winter kill. Drilling holes through out the winter could release some methane from under the ice but it's effects on oxygen levels in the water will be an unknown until Spring. Our extremely successful aquatic vegetation control in the Spring caused massive die of weeds. In turn the weeds sunk to the bottom and started decomposing. As they decomposed they in turn re-released nutrients stored in the plants back into the water. This in turn created a massive algae bloom in the Summer/Fall. This algae and remaining decomposing plants are probably the main potential cause for methane build up under the ice. Area around the hole would typically be a little slushier than normal ice.

4. Water currents can also have odd localized effects on ice formation. In our lake we get strong, observable water currents forming as a result of the water fall creek system. As we ran the water fall late into the Fall it is highly possible that these water current persisted long enough to cause differential ice thickness formation. These areas of thinner ice could of formed pockets for methane from rotting vegetation to build up. Ice forms from the surface down. Therefore any erosion in a small area creates a pocket to trap gases.

5. Debris on the surface. In walking around last week I observed no debris that could cause this. Dust, soot and dirt build up would normally only cause ice weakness in areas that get stronger sun such as found in the Spring time. This early in the season should not be a factor. Multiple areas of occurrence suggests this could not be a factor.

6. We do not run a wind mill or other oxygenation system during the winter. This is not a factor.

7. Intentionally made hole from vandals or pranksters. Kevin W's description is clear this is a natural occurrence and not man made. Therefore I do not suspect this is what happened and therefore unlikely.

8. On large lakes the warming and cooling of ice along with wind can create pressure ridges that can create large gaps or thinning of ice. Our lake is too small for this.

I can't think what else could be involved...any ideas? Just be careful as their could be really weird ice out their with such a late but quick freeze.

[Drano]

This just goes to show everyone that we all have to be very careful when out on the ice.

Thanks for the post Sundance..

Be safe everyone...:wave::wave:

[madatter]

I just drove from the Hat to Calgary yesterday,punched holes in Brooks trout pond,Newell,Badger and Mcgregor.
Newell has a nasty pressure ridge out from the boat launch that's scary.I went to the south end on Little Ranier and ice is a very solid 15".No one looks to have been driving on the ice at Newell.
Badger was in the same condition with 15" of solid ice and a couple of trucks on the ice.
Mcgregor the same condition with some guys on the ice at the south end of the campground.
All in all ice conditions are pretty good but there is no way I'd be driving all over the place.
Rattlesnake near the Hat had 6" of ice before the freeze and now has 12-14"...
Hoope this helps some people out there....

[Shmag]

I am wondering if you don't have gas coming out of the bottom of the lake in that spot. I beleive we have them on slave near faust bay, you can have 3ft of ice and then you come to a series of holes big enough to drive a school bus into. With the center of it bubbling, think it would be gas maybe an oxygen spring, not sure but maybe you have a small one there.