Flood Review

[Frisk]

I think they did a good job bringing down the lake level this year. It should balance out nicely once the snow pack finishes melting.

[tsayta]

The turnaround in lake level is even faster than last year. Image below shows changes in the past month alone:

Lake level May 3.JPG

[attachment=0]

Ummmm, not really. You have to back out the time scale on your chart to a wider time view. Last year was steeper and we are nowhere close.

[andrea-lake]

Mission Creek is forecast to exceed 100-year flows. Last year they peaked at 80 m3/sec in May. This year the flows are forecast to peak at 135 m3/sec on May 10th or 11th.

[andrea-lake]

Re: the quick turnaround of the lake shown in my earlier post, tsayta wrote:
'Ummmm, not really. You have to back out the time scale on your chart to a wider time view. Last year was steeper and we are nowhere close".
Thanks for your response. Yes, the larger time scale helps put things into perspective. However, it will be very clear by the end of next week that the U-turn in the lake level will be much sharper this year than last your.

[andrea-lake]

Shaun Reimer published an official forecast of the lake level in the May 8th webinar by the Okanagan Basin Water Board. Simply put, he's forecasting the lake will rise above full pool by 10 to 25 cm around mid-June. In the previous webinar of April 16th, he said that water management thought they would be able to keep the level below full pool because they had drawn down the lake in advance. For those who want links to the full presentation as well as a simple chart that compares his forecast to last year's peak level, see my May 11th post in "Monitoring lake level to prevent flood" at the link below:

viewtopic.php?f=119&t=77601&start=30

[Jflem1983]

Shaun Reimer published an official forecast of the lake level in the May 8th webinar by the Okanagan Basin Water Board. Simply put, he's forecasting the lake will rise above full pool by 10 to 25 cm around mid-June. In the previous webinar of April 16th, he said that water management thought they would be able to keep the level below full pool because they had drawn down the lake in advance. For those who want links to the full presentation as well as a simple chart that compares his forecast to last year's peak level, see my May 11th post in "Monitoring lake level to prevent flood" at the link below:

viewtopic.php?f=119&t=77601&start=30

A foot above full pool doesent sound too bad. I do not understand the juggling act. Why not build a large water pipeline to feed the southern farmers of the Okanagan. Once we had deep water access to lake water pumped to a station or tower in oliver say. There would be less need to balance lake levels and stream flows. We would have irrigation and flooding under control whioe creating jobs

[andrea-lake]

Lake level U-turn - comparing 2018 with 2017.

The blue line in the chart below is 2018 and the green line is 2017. Last year, the lake started rising in mid-March and it rose a total of 100 cm by May 15th. In contrast, this year the lake started rising the last week of April and it's already risen 92 cm in a much shorter period. Does anyone think the blue line will cross the green line by next Wednesday?

[tsayta]

Lake level U-turn - comparing 2018 with 2017.

The blue line in the chart below is 2018 and the green line is 2017. Last year, the lake started rising in mid-March and it rose a total of 100 cm by May 15th. In contrast, this year the lake started rising the last week of April and it's already risen 92 cm in a much shorter period. Does anyone think the blue line will cross the green line by next Wednesday?

Lake level comparison 2018-2017.jpg

Nope

[bob vernon]

I'm listening to a story on CBC about the flooding. One Rock Creek resident said that it was great that the province replaced her kitchen appliances last year and she was thankful. She also wondered if the province would do the same thing again this year. And there were a bunch of other folks who got flooded again. And they were upset. They ran out of time to strengthen their dikes around their ranch on the flood plain. They knew the snowpack was heavy and likely to cause another flood this year, but they ran out of time. They've had months of notice.

I'm all for helping these people. As long as they move from the flood plain. And our regional districts should put a halt on any building permits on the flood plain. The insurance rates for all of us goes up whenever a bad flood season, or fire season happens. It's gotta stop. We can't be replacing that lady's appliances year after year.

[andrea-lake]

Below is a chart of the remaining snow pack (blue line at the top) as of May 15th showing there is more snow now than at the same time last year. This increases the probability of the 2018 line passing the 2017 line (see my previous chart of 2017 vs 2018 lake level U-turn). Furthermore, at this time Mr. Reimer is keeping the discharge rate at Penticton Dam much lower than last year, which further increases the probability that the 2018 line will exceed the 2017 line by next week. Reducing the discharge is understandable, given the current flood issues south of Penticton.

[Frisk]

Does anyone think the blue line will cross the green line by next Wednesday?

A couple of weeks ago I would've said there's absolutely no way but seeing the channel flow restricted and the rain dump in the forecast I'm not totally sure anymore.

[Glacier]

The Brenda Mine snow pillow was completely melted a couple of days ago..

[gman313]

Below is a chart of the remaining snow pack (blue line at the top) as of May 15th showing there is more snow now than at the same time last year. This increases the probability of the 2018 line passing the 2017 line (see my previous chart of 2017 vs 2018 lake level U-turn). Furthermore, at this time Mr. Reimer is keeping the discharge rate at Penticton Dam much lower than last year, which further increases the probability that the 2018 line will exceed the 2017 line by next week. Reducing the discharge is understandable, given the current flood issues south of Penticton.

Snow pack May 16th.jpg

the snow pack in the mission creek watershed is actually lower than it was on May 15 last year.

[andrea-lake]

The last official forecast of the lake level was in the May 8th webinar by the Okanagan Basin Water Board, where Sean Reimer predicted the lake would peak at 10 to 25 cm over full pool. We now have the Pentiction EOC, working with the Province, predicting 52 cm above full pool. This is only 27 cm below the peak in 2017.

http://www.penticton.ca/assets/City~New ... levels.pdf

Is there anyone who can get an update from Mr. Reimer as to his forecast now, with a clear statement of the assumptions, such as the planned discharge at Penticton Dam, expected rain, temperatures and remaining snow pack?

[DGMOK]

Sean Reimer predicted the lake would peak at 10 to 25 cm over full pool and Pentiction EOC predicting 52 cm above full pool.
That is a 27 cm or almost 11" difference.
Would sure be nice to see a current prediction.