POSTED BY ERIC SPRAGUE ON MAY 17, 2023
If you intend to spend time on the Dolores River below McPhee Reservoir, please read this entire post. We’ll be updating here twice weekly, usually on Tuesdays and Thursdays, and this is the best source of information on downstream releases from McPhee. At the bottom of this post are some links to flow data sources and recreational organizations including Dolores River Boating Advocates and American Whitewater. These organizations can tell you more about what to expect floating the Dolores downstream of McPhee.
McPhee is releasing approximately 4,000 CFS, which is where releases are expected to remain until Thursday, May 18th. Depending on inflows, there is a good chance releases will ramp down to 3,400 CFS for the weekend. If they do, then releases will start ramping down late Thursday, and will likely ramp back up to 4,000 CFS on the morning of Monday, May 22nd. Otherwise, releases may remain at 4,000 CFS through the weekend. Check back Thursday for confirmation.
Currently, we are planning to reduce releases for Memorial Day weekend. Based on the current runoff forecast, we expect to begin ramping down to 3,400 CFS on Wednesday, May 24th.
One of the ecological goals for this year’s release is to run some lower raftable flows to accommodate a fishery sampling run by CPW in late May. For this, the plan is to get releases down to 1,200 CFS by Tuesday, May 30th and hold there until Thursday, June 1st. To reach that rate, releases will ramp down steadily over memorial day weekend. We’ll provide more info on this ramp-down in future updates when there is more certainty in the inflow forecast. On June 1st, releases are expected to ramp back up to a flow that stabilizes the reservoir elevation.
For planning purposes, raftable flows (1,200 CFS or more) are expected to continue through the first week of June. Be aware, this is a forecast, and the true length and volume of the spill remain unknown. Releases below McPhee can change at any time, though operators will endeavor to minimize unannounced changes. The later we get into the runoff season, the less certainty there is in release rates, and when the seasonal recession begins, releases will mimic the pattern of reservoir inflows more and more as operators will focus on keeping McPhee full through the end of the spill.
The short-term weather forecast is still calling for cloud-cover and afternoon thunderstorms through the weekend. These types of storm systems tend to be inconsistent and have unpredictable impacts on the runoff. Reduced solar radiation can slow the snowmelt, but rain-on-snow can trigger spikes of high flows where these storms manifest at high elevations. Running 4,000 CFS over the weekend opened some more storage in McPhee to absorb these potential spikes, and McPhee is currently sitting at a water surface elevation of 6917.4 FT.
As usual, we will continue to monitor conditions and will update this page as the spill progresses.
The following is a message from Dolores River Boating Advocates:
As releases from McPhee exceed 3,000 cfs, the water becomes swift with limited eddys. It is important to be aware of your location on the river, especially if navigating through Snaggletooth or the rapids below Gateway. Camps will become inundated in some cases, and in others hard to catch or overgrown.
Potential hazards include bridges at high water levels with potentially limited clearance. Additionally, as the river rises, logs and wood will become mobilized and possibly create strainers and hazards. Further, in some areas, the channel may be braided, and it is important to be alert and aware of various options.
As flows increase or decrease, be sure to be aware of fluctuations and tie your boats up appropriately. Always bring necessary safety gear, and required equipment including a groover and firepan.
For more details on the current official forecast, go to https://www.cbrfc.noaa.gov/wsup/graph/front/espplot_dg.html?year=2023&id=MPHC2
Dolores Gage: https://waterdata.usgs.gov/nwis/uv?09166500
McPhee Elevation & Capacity: https://dwr.state.co.us/surfacewater/data/detail_tabular.aspx?ID=MCPRESCO&MTYPE=STORAGE
Dolores below McPhee: https://dwr.state.co.us/surfacewater/data/detail_graph.aspx?ID=DOLBMCCO&MTYPE=DISCHRG
Slickrock Gage: https://waterdata.usgs.gov/nwis/uv?09168730
Bedrock Gage: https://waterdata.usgs.gov/nwis/uv?09171100
Bureau of Land Management: https://www.blm.gov/visit/dolores-river-srma
The BLM has a detailed boating map of the Dolores river posted on their website. Link below.
BLM Avenza Map page for the Dolores: https://www.blm.gov/documents/colorado/public-room/map/colorado-dolores-river-100k-boating-map-17×40
The following are links to the American Whitewater River Inventory pages for the lower Dolores River: