2013 Flood Forecast

By: plapman , 9:33 PM GMT on February 28, 2013

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I'm late getting online today.
Another morning spent in the ER.
I've got a new diease to add to my collection. COPD.
Yestrerday the province release the flood forecast for today. it's just in time for me to have completed the flood orotection series.
The The forecast is kind of sketchy but a new one will be issued in March. A lot depends on the rate of melt.
manitoba's flood forecast from the Provincial News release site.
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Hydrologic Forecast Centre
Manitoba Infrastructure and Transportation
Winnipeg, Manitoba
FIRST SPRING FLOOD OUTLOOK FOR MANITOBA
February 27, 2013
Overview:
The Hydrologic Forecast Centre of Manitoba Infrastructure and Transportation’s first 2013 spring
flood outlook notes that the potential for 2013 spring flood is higher than in 2012 mainly due to more
widespread snow pack with higher water content, ranging from average to above average in many
parts of the Province. However, the flood potential is significantly lower than in 2011 due to
considerably lower soil moisture levels. Prior to the unprecedented 2011 floods, Manitoba
experienced widespread, high soil moisture levels followed by heavy precipitation amounts in winter
and spring.
The outlook notes that there is a risk of minor to moderate spring flood potential for the Red, the
Souris, the Pembina and the Assiniboine Rivers, and in the Interlake.
Spring flooding is likely in portions of northern Manitoba including The Pas where there is above
average soil moisture conditions and significant snowfall this season. The main stem of the
Saskatchewan River at the Pas is unlikely to exceed bank levels.
Significant rainstorms occurring this spring could result in localized flooding, including some portions
of the upper Assiniboine and Souris River basins, the Interlake Region and in The Pas area.
The spring flood potential is still very dependent on weather conditions from now until the spring melt.
The amount of additional snow and rain, the timing and rate of the spring thaw, and the timing of peak
flows in Manitoba, the U.S. and other provinces will have a significant effect on flood potential.
The chances of minor localized flooding during the early part of the runoff period due to ice jams or
snow blockages in drains, ditches and small streams is fairly low. Although major ice jams are
unlikely to occur, the possibility cannot be ruled out especially in the Interlake region and the Upper
Assiniboine River. The North Red Community Water Maintenance Corporation will be focusing the ice
jam mitigation program on the north Red and the Assiniboine rivers to reduce the potential of ice jams
on these rivers.
Climatic Conditions
 Precipitation during the autumn of 2012 was well below normal in most of southern Manitoba
but near normal to above normal in the Interlake Regions and Northern Manitoba including the
Pas Region. This is in contrast to 2010, when autumn precipitation was above average and
widespread across the Province prior to the floods of 2011.
 The long term March-April climatic outlook calls for a good chance of normal temperatures in
southern Manitoba with precipitation amounts ranging from normal to above normal, with
heavier amounts forecast for Interlake region.
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Soil Conditions
 The overall soil moisture levels at the time of freeze-up in 2012 were significantly lower than
the unprecedented and wide spread wet conditions seen in 2010 prior to the major 2011
floods.
 The aerial soil moisture survey conducted by the United States, National Operational
Hydrologic Remote Sensing Center (NOHRSC) in November, 2012 indicated that moisture in
the top 20 cm of soil was generally below average in Southern Manitoba and in the U.S.
portion of the Red River basin (Figure 1). Some of the data particularly in portions of
Saskatchewan was unreliable due to early snow cover impacting the soil moisture
measurements.
 An Agriculture and Agri-Food Canada soil survey shows conditions in the prairies ranging from
below normal to above normal soil moisture levels (Figure 2). Soil moisture maps in the root
zone (0 – 120 cm) from fall 2012 field surveys produced by the Manitoba Agriculture, Food and
Rural Initiatives (MAFRI) for Southern Manitoba are shown in Figures 3 and 4. The maps
indicate soil moisture content varying below normal to near normal in most parts. A few areas
including the Interlake area show above normal soil moisture levels.
 Analysis based on weighted May to October precipitation shows that the soil moisture at
freeze-up time was variable across Manitoba with above average levels in central and northern
Manitoba including The Pas and Interlake areas (Figure 5). Most of the Southern Manitoba
including the Red, the Assiniboine and the Souris watersheds experience below normal soil
moisture levels.
 Soil frost information is scanty but available data from southern Manitoba indicates the soil is
frozen to a depth from 50 cm (1.5 feet) to 100 cm (3.0 feet) largely due to periods of well below
freezing point temperatures. Wet frozen soils impede infiltration of melt water and increase
spring runoff. Higher runoffs occur if the snow melt is rapid.
Lake Level and River flow Conditions
 At the time of freeze-up, water levels for the Red, the Assiniboine, the Souris, the Qu’appelle
and the Winnipeg Rivers were below normal and lower than the levels in 2010 and 2011. The
Saskatchewan River at The Pas, the Waterhen and the Fairford Rivers were above normal but
close to or lower than the fall of 2010 and 2011. Water levels for the major lakes, i.e. Lakes
Winnipegosis, Manitoba and Winnipeg were also below the levels seen in 2010 and 2011 at
the time of freeze-up.
 Major rivers have ice cover and flows either below or close to normal for this time of year, and
generally below those of February 2011. Interlake major rivers, the Waterhen and the Fairford
Rivers are running above normal due to consistently high water levels especially in Lake
Winnipegosis. The Assiniboine River is also high for this time of year due to releases from the
Shellmouth reservoir.
Snow Water Content
 November to February snowfall has been near normal (100%) in most parts of Manitoba,
(Figure 6).
 Along the Manitoba/ Saskatchewan border, above normal (200 to 240%) snow pack exists.
 The Manitoba portion of the Red River basin has 100 to 200% of normal snow pack.
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 Near normal to about 200 % of normal snow pack exists in the North Western portions of
Manitoba.
 According to the U.S. National Weather Service recent storms have increased snowpack in
upper Red River basin area upstream of Fargo.
 The U.S. and Saskatchewan portions of the Souris River have snow packs ranging between
100-150% of normal.
 Based on mid February field and air based surveys, snow water equivalent in the snow pack
ranged from 70 mm (2.8 inches) to 120 mm (4.7 inches) in the Upper Assiniboine and 60 mm
(2.4 inches) to 130 mm (5.0 inches) in north western parts of Manitoba.
Spring Run-off
 The 2013 potential spring runoff is expected to be variable, ranging from below normal to
normal in most parts of Manitoba and near normal to above normal in portions of northern
Interlake, The Pas areas, and the Turtle Mountain and the upper Assiniboine River watershed
(Figure 7).
 Spring runoff could change significantly if future precipitation and breakup conditions differ
from the average.
River Ice Conditions and Ice Jamming
 Due to periods of well below freezing temperatures this winter, ice thickness in the Red River
ranged between 46 cm (1.5 feet) and 76 cm (2.5 feet). This thickness is unusually higher than
normal for this time of the year. Ice thickness varies according to the size and the location of
the river and typically ranges between 30 cm (1.0 foot) and 61 cm (2.0 feet) in major rivers like
the Red River and the Assiniboine River. Spring weather in the weeks prior to spring breakup
affects deterioration of ice and will be a significant factor in determining ice strength at breakup.
 It is virtually impossible to predict the time of occurrence and extent of ice jamming. However
with the extensive ice cutting and the Amphibex ice breaking activities ice jamming and related
flooding on the lower Red River should be limited. Localized brief flooding can occur where ice
jams develop, even with below average river flows.
River Forecasts
Spring flood outlooks are based on three weather scenarios that look at additional snow, melt rates
and spring rain fall based on statistical analysis of the past 30-40 years of climate data. The three
future weather scenarios are referred to as ‘favourable’, ‘average’ and ‘unfavourable’. The terms
‘favourable’, ‘average’ and ‘unfavourable’ are referred to as the lower decile, median and upper decile
conditions, respectively. There is a one-in-ten chance of the weather being ‘favourable’ or better and
there is a one-in-ten chance of it being ‘unfavourable’ or worse.
Red River Main Stem
The potential for spring flooding is low to moderate in the Red River Basin. Soil moisture conditions
are generally below normal with near normal to above normal snowpack in most of the basin.
 With favourable weather from now on, no flooding is expected.
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 For median conditions, there could be minor flooding but levels would be lower than to those of
2001.
 With unfavourable weather conditions, minor to moderate localized flooding could occur
especially in small tributaries such as the LaSalle, the Rat and the Morris Rivers. Levels in the
main stem would be close to those seen in 2011 from Emerson to Winnipeg. There should be
sufficient community protection to prevent any over bank flooding as dyke elevations are
higher than the predicted flows (Figure 8).
Operation of the Floodway and the Portage Diversion
 Levels at James Avenue are forecasted to be 4.28 m (14.05 feet), 5.29 m (17.34 feet) and 6.00
m (19.68 feet) for favourable, average and unfavourable weather conditions, respectively.
 Lower decile scenario requires no operation of either the Red River Floodway or the Portage
Diversion.
 Median scenario requires minor use of the Floodway and Portage Diversion. Water would only
be a few feet above the Floodway entrance berm. No flood issue would be expected with local
access in RM of Ritchot.
 Upper decile scenario would require greater use of both the Floodway and the Portage
Diversion.
Pembina River
The flood potential is expected to range from minor to moderate in the Pembina River. The average
weather scenario would produce little or no flooding. Due to above average snow water equivalent in
the snow, an unfavourable weather scenario could produce minor to moderate flooding with levels
close to those of 2005.
Roseau River
The spring flood risk is low to moderate on the Roseau River. The soil moisture levels are generally
below average while the snow water content ranges from normal to above average. The average
weather scenario would produce minor flooding, and the unfavourable weather scenario could
produce minor to moderate flooding with levels close to those of 2011.
Assiniboine River
The flood potential is moderate on the Assiniboine River due to normal to above normal average soil
moisture in the upper portions of the watershed and normal to above normal snow water equivalent in
most of the basin.
 With favourable weather conditions, little or no flooding along the Assiniboine River is expected
this spring.
 With average weather from now on, minor flooding could occur on the low lying portions of the
upper Assiniboine River.
 The unfavourable weather scenario would result in moderate flooding of the Assiniboine Valley
from Shellmouth to Brandon, similar but generally lower than 2006 (Figure 9a and 9b).
 Operations of the Shellmouth Dam are expected to achieve a low drawn level of 1384 ft (421.8
m) by the end of March to provide storage capacity for reservoir inflows to reduce flooding
downstream.
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 The Portage Diversion will be operated in accordance with the operating guidelines to manage
ice jamming on the Assiniboine River east of Portage and to provide flood protection to the City
of Winnipeg.
South West Manitoba and the Souris River
There is potential for moderate flooding in the Souris River and the vicinity as the result of average to
above average winter precipitation in the North Dakota, Saskatchewan and Southern Manitoba
portions of the watershed. The unfavourable weather scenario would result in flooding with peak
stages similar to those of 2009. The Town of Melita has sufficient dike elevation to protect against
overbank flooding.
Interlake Region
Both soil moisture and winter precipitation are normal to above normal in the Interlake Region. With
favourable weather conditions from now on there is little chance of flooding. Average weather
conditions are expected to cause minor flooding while moderate flooding is expected with
unfavourable weather conditions. The Fisher River could experience minor to moderate flooding with
levels close to those of 1982.
 Fairford structure flows will remain at maximum discharge through the rest of winter. The river
flow is expected to be above normal under both upper decile and average weather conditions
but below levels seen in 2011.
Eastern Region
Both the soil moisture and the snow water content are below normal in south eastern area but near to
above normal in the Berens River area.
 Favourable weather conditions are not expected to produce flooding
 The average weather scenario could lead to minor flooding.
 The unfavourable weather scenario could produce minor to moderate flooding in the low lying
areas along including the Poplar, Bloodvein and Berens rivers.
Lakes
 Lake Manitoba is expected to be within their operation ranges at the end of spring runoff. With
median conditions the lake is expected to peak below the top operating range of 812.5 feet
and then to decline there after depending on weather conditions.
 Based on Manitoba Hydro analyses, with median conditions Lake Winnipeg is expected to
drop from its current average level of 713.4 feet (217.44 m) to 713.3 feet (217.41 m) by the
end of winter, rise to 713.7 feet (217.54 m) by end of May.
 Lake Winnipegosis is expected to decline under both the favourable and average weather
conditions. The level could rise to about 832.7 feet (253.81 m) under unfavourable weather
conditions which is more than two feet below the 2011 peak level.
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 The upper decile scenario of Red Deer Lake levels would likely be close to the peak level
(864.7 ft) in 2011 and one foot lower than the flood level (865.5 ft), while the median scenario
is likely close to the peak level in 1985.
 Dauphin Lake is expected to be in the range of target levels under both the average and
unfavourable weather conditions although favourable conditions will drive lake levels slightly
below lower target level.
 Shoal Lakes levels will experience less than one foot rise with favourable and median
conditions and two feet rise with unfavourable conditions.
Northern Manitoba and The Pas Regions
Soil moisture and snow cover are both near normal to above normal in Saskatchewan and Manitoba
portions of the Saskatchewan River Basin. Flooding is unlikely with normal weather conditions from
now on.
 The unfavourable weather scenario could produce localized flooding especially if there is a
rapid melt in the Pasquia area. The Saskatchewan River could experience levels similar to
those of 2007. The river would be expected to remain within its banks. The Carrot River is
expected to approach but not overflow its banks with levels close to those experienced in
2007.
Soil moisture in the Thompson area is above normal with the snowpack being near normal. Local
runoff conditions are likely to be normal. Runoff in most of the northern Manitoba, north of latitude 54,
is expected to be near normal.
 Additional information for Northern lakes can be obtained from Manitoba Hydro.
Flood Preparations
 The Manitoba government and municipalities are continuing to prepare for spring flooding.
This includes work with municipal emergency management teams to review existing
emergency response plans, gather information through conference calls and floodpreparedness
meetings and other related activities.
 The ice-jam mitigation program north of Winnipeg has begun with ice cutters and Amphibex
machines working along the Red River. To weaken the ice, approximately 12 km of river icecutting
is complete. The Amphibex AE400s have broken a channel down the center of the river
approximately 6 km long.
Forecast Updates
 This forecast will be updated in late March when further precipitation and other weather details
are available.
Detailed forecast (Text and Charts) available at
Link

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5. WunderAlertBot (Admin)
8:19 PM GMT on March 02, 2013
plapman has created a new entry.
4. shoreacres
1:23 PM GMT on March 02, 2013
That's quite a flood forecast! Really, the most interesting to me is the ice-jam mitigation program. It makes perfect sense, of course. It's just so different from anything we have down here, lacking ice as we do. ;)

(Now that I think of it, there was a week a couple of years ago I had to break ice on the bird's water bowls. I guess you could call that ice mitigation.)

Sorry to hear about the COPD. I've got a cousin who deals with that. No fun, at all, but once she got on medication and a program it improved greatly. As she said, "Knowing what I was dealing with was a great help." How's that for an understatement?

Have a great day - give Abbey a scritch for me!
Member Since: October 4, 2004 Posts: 205 Comments: 15288
3. Alleyoops
12:36 PM GMT on March 02, 2013
Good morning TONY. Just read that you now have to cope with COPD as well as your other co-mobilities. Darn, just more meds to add to your regiume. You will soon be a walking pharmacy as well as me. Thank goodness we don't have to pay for our meds, if we did, I would probably be down to just two of the major ones and the rest would go. I take 12 pills a day. Way too much for someone who always refused to take them before if I could. I still refuse to take any STATIN for cholesterol and rather lower it with diet. Wish I could do the same with Diabetes. Maybe once I lose more of this weight, I can at least cut down on some of these pills. So far I have lost 30 lbs since Xmas. Still lots to go.

Anyway have a great day. Stay warm and perhaps you better get the inflatable ready just in case of flooding when it finally does warm up. So finished with this winter. I want temps in the 60s so my old bones can thaw out.
Member Since: April 18, 2007 Posts: 190 Comments: 29418
2. masshysteria
6:59 PM GMT on March 01, 2013
Good Afternoon, Tony!

Sorry to learn that you ended up in the ER the other morning and have found that COPD is now added to your list of post-strokes symptoms. My hubby developed it after his original stroke, too, and has had to take a puff of Spiriva (tab inside inhalor) every night before going to bed. It's helped considerably, especially, in reducing once serious phlegm problems. Hope that you, too, are given easy access to this or another similarly helpful inhalor to curb your effects!

Reviewing, somewhat, your Canadian flood zone list above, it looks like many lakes and other regions near or around Manitoba could potentially be in harms way. I know that this past February was the 5th snowiest on record, around here, but thankfully we've been experiencing a more of a gradual, manageable melting process. Whew! I still remember the serious flooding that took place in our and surrounding cities/towns a couple years ago. Much devastation to those living alongside rivers or streams. Glad we live more above ground and far enough away to be seriously effected. Hope the same applies to you!

Again, hope you're feeling better today and that you find solid relief from your newer COPD symptoms!!
Member Since: June 21, 2006 Posts: 62 Comments: 7605
1. GRANDMANAN
6:59 PM GMT on March 01, 2013
Afternoon Tony, sorry to learn of the COPD, hang in there.
Flood forecast seems to have some unknowns alright, still seems potential for problems if mild weather comes and stays for a few days.
Snow continues here on the Bermuda of the Maritimes, lots down after 60mm of rain yesterday, needless to say quite a mess for road crew to keep ahead of. Road is bare, lots of salt and temp around or a little above the freezing level.

ROB
Member Since: June 26, 2005 Posts: 3246 Comments: 1461

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About plapman

Retired and loving it. If I'd have known about retirement befor I started my 40 year career with the government of Manitoba I'd have retired first. :)

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