POSTED BY ERIC TANNER ON APRIL 17, 2017
2017 McPhee Release Update
April 17, 2017: MCPHEE DOWNSTREAM RELEASES CONTINUE AT 1,100 to 1,200 CFS through the week. See below for more detail about future anticipated changes.
Summary: The near term forecast holds at mostly sunny with steady temperatures until later in the week. The higher runoff started late last week, and the reservoir elevation rises slowly towards the next trigger around 6920.
The April 1st forecast did not change quantity and we continue working on various scenarios to achieve multiple goals including: optimum flows of 1,900 – 2,000 CFS, high flows of 2,500 – 4,000 CFS and continue releases through Memorial Day weekend. We still expect to release around 250,000 AF that will make McPhee releases last approximately 60 days. More detail below.
Continue to watch the releases below McPhee at http://www.dwr.state.co.us/SurfaceWater/data/detail_graph.aspx?ID=DOLBMCCO&MTYPE=DISCHRG and the gages linked below.
We continue to monitor reservoir elevations versus inflow which are tracking as predicted by the near term weather forecasts and resultant melt models. A front coming in mid-week followed by a weekend front will be the next drivers of inflow and we wait to see how this may slow the runoff rates. Based on the continued inflow we will adjust releases to maintain 6920 by the end of April. The higher inflow is raising the reservoir elevation that in turn should trigger higher releases in the ”Optimum” range of 1,900 to 2,000 CFS later this month.
We still plan for the higher boating releases, 2,500 to 4,000 CFS, in early May and will give 2 weeks’ notice hopefully next Thursday. It still looks like we will reach appropriate trigger elevations in the first half of May and hope to solidify our schedule next week on the optimum flows followed by the higher boating releases.
After the higher release peak, downstream flows will vary, but remain boatable, to raise the reservoir elevation ahead of the Memorial Day weekend. 2017 Operations are still forecast to release 250,000 AF downstream over a minimum of 60 days taking us to Memorial Day weekend. Final release rates over Memorial Day will depend on how April & May inflow comes down and final April – July runoff volume.
SLICKROCK: Slickrock put-in/take-out access will happen on private property downstream of Hwy 141 bridge (bridge crosses Dolores River) about 200 yards past bridge on river left. Look for small flagging in bushes on left. DO NOT use the old boat ramp on river right upstream of bridge. That is private property and is not accessible this season. Additional info about Slickrock access here from DRBA: www.doloresriverboating.org
BEDROCK BRIDGE: The temporary equipment bridge (the low clearance one) was removed Thursday afternoon March 30. No intermittent closures are expected for a week or two. When a more definitive start date is available CDOT will provide notice. Please see their website at https://www.codot.gov/news/2017-news/march/caution-to-boaters-near-co-90-bedrock-bridge-low-bridge-in-place-through-april-8-intermittent-river-closures-begin-mid-april and look for signs, spotters and other guidance from the contractor, SEMA Construction, when the intermittent closures are active.
American Whitewater also provides good information about this year’s rafting opportunities and details for boaters at http://www.americanwhitewater.org/content/River/detail/id/385/.
DOVE CREEK PUMPHOUSE ROAD: Please be careful of heavy traffic in and out of the Dove Creek Pumps launch site. The road narrows and trucks with trailers cannot pass each other at certain points. Consideration of others and patience are appreciated here.
Rico Gage: https://waterdata.usgs.gov/nwis/uv?09165000
Dolores Gage: https://waterdata.usgs.gov/nwis/uv?09166500
McPhee Elevation & Capacity: http://www.dwr.state.co.us/SurfaceWater/data/detail_tabular.aspx?ID=MCPRESCO&MTYPE=ELEV
Dolores below McPhee: http://www.dwr.state.co.us/SurfaceWater/data/detail_graph.aspx?ID=DOLBMCCO&MTYPE=DISCHRG
Slickrock Gage: https://waterdata.usgs.gov/nwis/uv?09168730
Bedrock Gage: http://waterdata.usgs.gov/nwis/uv?09171100
Ramp down is not currently expected until early June, but that schedule could change depending on continued spring weather. The snow on the ground that is starting to melt will carry us through the first 45 days. When the Dolores Inflow matches the McPhee outflow on the way down a last peak we will start ramping down. From 800 CFS down we cut back to 600 over 24 hours and then hold for 24 hours. This pattern repeats through 400, then 200 then down to 75 CFS and we’re done. Ultimately you will have 4 days from 800 CFS to below 400 CFS when the releases start down.