Nechako River Update
Friday, December 23, 2016 @ 3:47 PM
There has been very little change in the stationary ice situation, it is still about 12 kms long upstream from the confluence with the Fraser River.
Several open channels of water are still visible, and the City says water levels are “trending down slightly”.
The Heritage River Trail remains closed between Cameron Street Bridge and the replica bridge, and parking lots at the boat launch and Kiwanis Park are also closed.
Monitoring of the River will continue through the holidays at specific locations and at regular intervals.
Comments
There are two types of floods in Prince George at the confluence of the Nechako and Fraser Rivers. We have the spring floods that basically flooded all the South West area of Prince George from the old Cameron St., Bridge to the City Yards on the East end of the City this area was under water almost every spring. In addition we had flooding in the winter caused by extreme build up of ice at the confluence of the Nechako and Fraser River.
The building of the Kenney Dam in the early 50’s eliminated the huge spring floods and the last (and biggest) was in 1948. So basically we still have flooding, however not at the level prior to the Kenney Dam. The Nechako river water flow was reduced by the Kenney dam by 30%. This water now goes through Kemano One tunnel and empties into the Pacific Ocean on the West Coast around Kitimat BC.
The natural flow of the Nechako was on the South side and it entered the Fraser at the South West side just North of the CN Bridge. The Fraser River entered on the East side. So if you were to stand on the high river banks in Fort George Park you could clearly see the brown muddy water of the Fraser on the East side, and the clear water of the Nechako on the West side as the river flowed past the park, South Ft George and on to the coast.
The result of the ice jams prior to 1948 were because of high water in both the Fraser and Nechako running into each other and icing up, and forcing the water to back up the Nechako. This back up was eliminated to some extent by the reduction of water in the Nechako and hence very few ice jams from the 1950’s forward to to-day. We did of course have the jams and flooding in 2008 and 2016, and it appears that the Nechako River water levels were at there highest level for both these years, and as a result we had more flooding.
The Nechako Rivers natural flow over the years has been changed as a result of extreme silting, and the main channel is now on the North Side and basically hits the Fraser close to the pulp mills as opposed to just North of the CN Bridge where it used to enter.
People who travel the Nechako by river boat will tell you that they used to go up the Nechako on the South side, and now must go up the Fraser almost to the pulp mills before going up the North Channel, so it is pretty obvious that the normal channel has been changed by silting.
The City is now in (or has just completed) trying to clear the South Channel through Cottonwood Park to allow water to by pass the ice jam and flow into the Fraser. The channel through Cottonwood part is a side channel, the main channel is a little further North.
If we were to dredge the South Channel and allow this ice to continue to flow into the Fraser and move South we would eliminate the threat of ice jams and flooding to some extent.
We know that we have less flooding and ice jams now than we had prior to the Kenney Dam. In fact one of the selling features of the dam was the reduction of the threat of floods. The high water in mid winter is unusual and results in ice jams and flooding from time to time, however history has show that we have had considerable reductions in the past 60 years.
We would have even less flooding and jamming if we would dredge the South side of the Nechako and the area just North,West, and South of the CN Bridge which would allow for higher and faster channels, and a more continuous movement of ice and water South of Prince George.
Eliminating the silted areas would reduce the possibility of this ice jamming on the sand and rocks, and reduce the risk of flooding. Reducing the amount of water into the Nechako during extremely cold weather would also be a big help.
Have a nice day.
“The building of the Kenney Dam in the early 50’s eliminated the huge spring floods and the last (and biggest) was in 1948.”
Nice story …… based on your imagination.
———————————————-
Headlines on page 1 of the June 8, 1964 (I do think that was after 1948!!) Citizen: Flood Waters Continue to Rise – forty families moved from Cache
Refugees from the island totaled some 300 people. The Fraser is now at the level established in 1956 – 32 feet.
Long time residents say this flood is the worst since the 1948 disaster.
Meanwhile, residents of the Bulkley Valley feel the worst of their spring flood threat is over. They made their observations today after rivers receded during the weekend, re-opening highway 16 to traffic after a week of flooding and washouts.
Headline from January 21, 2012: Ice Jam choking the Nechako
BC regional flood hazard officer Lyle Larsen said the level of the Nechako River has risen more than a metre in just two days this week. “It started jamming Wednesday early afternoon” Larsen said Thursday. “By Thursday morning the head of the ice cover had extended up the Nechako up to the Hart Bridge.”
Once the Fraser River freezes over, soft “frazzle ice” on the Nechako River has no place to go and starts piling up against the ice on the Fraser River, forming an ice dam, he explained.
That is what happened this year.
So, one of the take aways from this is that what happens at the Fraser, whether the spring freshets or the early winter extreme cold causing freeze up is the dominant cause of flooding at the confluence. As well, we must remember that there is flooding on other parts of the Nechako. Each has their own causes for flooding.
The information is available when one reads instead of dreams up stories based on no corroborated history.
1956 and 32 feet? I was there then. We had floods but no one was moved out between 54 and 59. Biggest problem after the water receded, and this happened late May and June every year was the stench of the 5 sloughs. Glad we moved because that garbage dump they had down there woulda been a huge stink.
Maybe it’s time to install a water aeration system and run air compressors only when needed. Air bubbles will melt ice very fast and it’s good for the fish.
I know that they work (while the temperatures are freezing but still relatively warm) for lake water to prevent ice from forming near the shore, especially where docks are located.
Lakes have large bodies of water, relatively deep. Air bubblers circulate the water, including warmer water, which prolongs the forming of surface ice.
let us just get all of city hall blowing across the river, with all the hot air they expel the ice jam should be gone in minutes
I think there are far more people on this site who are blowing hot air on this issue.
Comments for this article are closed.