POSTED BY ERIC SPRAGUE ON JUNE 13, 2019
McPhee is currently releasing high flows of approximately 3,400 CFS downstream.
- Managers increased releases on Sunday to 2,600 CFS to abate reservoir elevation gain as inflows into McPhee Reservoir exceeded projected peak inflows over the weekend.
- After receiving new forecast information Tuesday June 11th, releases were increased to 3,000 CFS yesterday morning.
- Current inflow forecasts are now predicting that another peak is forecasted to arrive this Friday or Saturday, and it may be equal to or potentially higher than the peak inflows experienced last Sunday, June 9th.
- Because of these forecasted high inflows, the uncertainty in the inflow forecast due to upcoming weather, and the reservoir nearing full, releases must now be managed on a more regular basis. Be aware that downstream releases may change on an hourly basis between roughly 2,000 CFS and 3,400 CFS through Monday June 17th. During this time, flows will not be scheduled to ramp down more than 800 CFS in a single day.
- Following the weekend, releases are expected to ramp down as inflows recede, though timing and target flows are still uncertain. Upcoming, smaller peaks in inflows while the river recedes are likely.
Releases will remain at or above 1,200 CFS through Sunday June 23rd, after which flows are yet to be determined. Based on the margin of error in current inflow forecasts, it is possible there will be additional rafting days after June 23rd – this should become more clear in coming weeks. Details on flows following June 23rd should be available the week beforehand. More details will continue to be announced on later posts.
The possibility remains for the next couple of weeks that inflows will increase significantly above modeled flows for brief periods. If the reservoir is too full when this occurs, managers can be forced to respond by increasing releases steeply with little notice. To mitigate the possibility of this when inflows peak this weekend, releases are now at high flows of about 3,400 CFS.
The option of allowing releases to fluctuate through the next few days was discussed with and approved by both rafting and ecological representatives. This option leaves open the possibilities of both reaching habitat maintenance flows above 3,000 CFS and varying releases (which alters river levels and the water table), each of which can benefit the downstream riparian ecosystems in different ways. When these changes occur between 2,000 CFS and 3,400 CFS, flows remain at either optimal or high raftable flows, allowing for viable recreation. The ability to fluctuate flows also allows managers to follow inflows as needed, within the range, to maintain desired reservoir elevations.
Please continue to check back on this site regularly for new updates, primarily on Mondays and Thursdays.
Currently, a high-pressure system is present over central Colorado, and above average temperatures are expected through Friday June 14th. The high temperatures combined with the substantial amount of snowpack remaining at high elevations are expected to sustain inflows around 4,000 CFS until the weekend.
Afterwards, a slow-moving low-pressure system is expected to move into the region and pass over the Dolores River headwaters – beginning this weekend and extending into next week –increasing cloud cover and precipitation. It is not yet known how much of an effect this system will have on inflows into McPhee.
If you have questions, the best way to address DWCD is through the “Contact” page of this website. Otherwise you can try calling 970-882-2164 extensions 5, 1 or 6.
A message from Dolores River Boating Advocates and American Whitewater:
“As these inflows from the mountains fluctuate and McPhee releases also fluctuate within low, optimal, and high flow ranges, consider how this can impact boating experiences overall. Making note of river levels anecdotally while on the river can be useful to maintain awareness of flow changes. As flows increase or decrease, take appropriate measures to keep your boat tied off appropriately so it is not beached nor is loose as flows rise. And note that the braided channel options will increase with increased water; stay aware of the various options.”
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
The following are links to the American Whitewater River Inventory pages for the lower Dolores River: