PRINCETON DAM UPDATES
In early May 2023, the DNR implemented a seasonal gate operation strategy plan for the Princeton Dam. The current plan is set to run from May 2023 through June 2026. Please see the bottom of this page for a full copy of the Princeton Dam Operation Plan. Below you will find current updates regarding gates, flow, and other pertinent information to the Princeton Dam.
The below updates are sent from Uriah Monday with the DNR.
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May 31, 2024
Wanted to give you a quick update on the gate closure plan:
First gate was closed on Friday May 17, a few days ahead of the scheduled date of May 20, due to levels likely to drop below threshold of 7.3. Gage at the dam read 7.48 at the time of closure and gage at Fish Camp read 2.09.
Second gate was closed on Thursday May 23, a few days ahead of the scheduled date of May 28, due to trained operators unavailable on other dates due to holiday. Gage at the dam read 7.45 at the time of closure and gage at Fish Camp read about 2.0 (estimated from photos on 5/21 and 5/24).
Third gate will be closed today, Friday May 31, a few days ahead of scheduled date of June 3, due to trained operators unavailable the week of June 3.
Fourth gate will be closed on Monday, June 10.
Final gate will be closed on Monday, June 17.
River flows appear to have reached their crest according to NWS and USGS data and will likely remain at a flow rate of just over 1200 CFS. This is comparable to flows we had at the very beginning of May this year, and is just a little less than the median value for all May 31’s on record – i.e. we are pretty dang close to ‘normal’. Some scattered rain chances are in the forecast for the upcoming week but nothing as significant as we recently experienced and it is unlikely that levels will rise further from rain. It is likely that the gage at the dam will read ~8.3 and gage at Fish Camp will read ~2.9 today before the closure. Today’s closure is likely to result in ~2” change at the dam, and less of a rise at Fish Camp.
While operation plan allows for gates to be closed sooner if the level measurement at the dam drops to 7.3, given the recent rainfall this is highly unlikely and closures should all happen on the dates specified above.
After the last gate is closed, the dam will remain closed at least until October 1 and, weather pending, until November 1 (see overall operation plan for conditions and details.)
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May 17, 2024
All - a slight modification to the first gate closure timing - the gage was checked today and it read a bit below 7.5. Given the warm (and nice!) weather expected this weekend, we closed one gate today instead of waiting until Monday to ensure the level did not drop below the “floor” of 7.3.
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May 17, 2024
Attached is a copy of the DNR’s overall operations plan that was distributed last year, for reference (see below). This year’s plan with specific dates is to:
Close one gate on Monday, May 20.
Close a second gate on Tuesday, May 28.
Close a third gate early in the week of June 3 (exact date TBD, depending on operator availability)
Close a forth gate early in the week of June 10 (exact date TBD, depending on operator availability)
Close the last gate on Monday, June 17.
Gates may be closed sooner if the level measurement at the dam drops to 7.3 (see overall operation plan for conditions and details.)
After the last gate is closed, the dam will remain closed at least until October 1 and, weather pending, until November 1 (see overall operation plan for conditions and details.)
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May 14, 2024
Last I reported, we anticipated opening all gates during the week of April 22nd. Due to fisheries staff commitments with sturgeon the opening of the last 2 gates did not happen until Monday, April 29th. Up until then, levels had remained relatively steady around 8.3 – 8.4. After all gates were opened, the levels stayed around 8.0 for a week or so, sustained by timely rain; since then they have slowly dropped to 7.6 as of today.
Looking ahead, the gate operation plan calls for closing one gate per week, starting the week prior to Memorial Day – so it’s coming up fast. I am working on arranging more precise dates for closures based on operator availability, and will be sending a separate operation plan email tomorrow or Thursday.
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April 19, 2024
I want to confirm to you that DNR staff opened a third gate on this past Tuesday morning. We have not taken a photo recently, but based on flows at Princeton (~1210 CFS) the level at the dam is likely around 8.2.
The flows that are being seen now, due to recent ample rain, are getting close to seasonal norms. For that reason, it is anticipated that we will go through the process of fully opening all gates next week. We’ve been running a little higher than the plan range for a couple weeks now (since our slushy snow/melt/rain event) and this should get rectified. Even with all gates open, the gage at the dam is likely to remain around a reading of 8.0 if flows continue as they recently have been (weekly rain of modest amount).
I would like to ask – how have levels at the lake itself been? Do they appear to be more normal for this time of year?
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April 14, 2024
DNR staff opened a gate (two gates now open) on Tuesday 4/9/24. It was expected that the river had crested already Monday, however, flow actually continued to rise marginally into Wednesday and at this time is at about the same flow rate as it had been Tuesday. Therefore, the staff gage at the dam is likely still reading around 8.5 rather than the 7.8 or so that I had expected.
Storms are anticipated Tuesday, which will likely boost levels further. I will verify the forecast later in the day tomorrow, but will anticipate opening a third gate early in the week and possibly a fourth gate later in the week as flows continue to recover toward amounts typically seen in this season.
I will send an email confirming the plan sometime on Tuesday.
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April 8, 2024
In my update on 3/29, I indicated that if we received wet weather for some consecutive days, and the level rose over 8.1 and was expected to stay elevated, I would anticipate re-opening a gate. After last week’s rain and melted snowfall which appears to have totaled around 2” of rain equivalent watershed wide, the gage at the dam has risen to nearly 8.5. Flow in the river is nearing 1100 CFS which is close to double what it had been prior to precipitation. (Some ‘good’ news as a side note – this amount of flow is now more than the 25th percentile for this time of year, so while not quite what everyone would call ‘normal’ it’s definitely in a better place. Hopefully regular rainfall can sustain this.)
There is a small amount of rain in the forecast for Thursday but otherwise weather appears dry over the next 7-10 days. In dry weather the flow rate typically recesses at about 30 CFS/day, so in 10 days from now I would expect the flow to remain at least 800 CFS. The current level would warrant opening a second gate per the operation plan, and after the estimated 10-day outlook I would expect the gage at the dam to read around 7.8. It will be interesting to see how/whether the Fish Camp gage responds in kind.
I have communicated with DNR technician regarding this gate operation, and it appears that he will be available to conduct a gate opening tomorrow. I will let you know when that happens.
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