Other Information Sources: CA-Creeks: RubiconPlacer County Water AgencyHell Hole Reservoir- WikipediaHell Hole Dam Failure photosSacramento Municipal Utility District (SMUD)FishSniffer article by Dan BacharUpper American River FoundationAmerican River Watershed GroupA GUIDE TO THE BEST WHITEWATER IN THE STATE OF CALIFORNIA, HOLBEK & STANLEY, 1988FERC Information: Hell Hole Dam is part of Placer County Water Agency's "Middle Fork American River Project, FERC Project #2079. The FERC license for this project expires in 2013.Project Relicensing Homepage
Licensing Process ScheduleRecreation Technical Study ReportsDraft Instream Flow Report
This is the usual put in spot. PCWA now has a flow gauge at this bridge, but it is not yet online. Boaters could also put in 8.6 river miles upstream at the dam.
Pilot creek enters from the left and may have a good flow in the winter and early spring.
Topo maps show a trail coming a short ways from a road down to the Rubicon here. This could provide access for a short 4.7 mile boating trip from Pilot Creek to Ralston.
Long Canyon Creek comes in from the right and can bring increased flow, especially in the winter.
The road comes close to the river just upstream of a powerhouse.
Flow Report from PCWA - May 11, 2011
Flows were fluctuating between 300 & 350 cfs at Ellicott Bridge, but are around 220 on May 11.
Flows just above Ralston Afterbay are about 550 cfs.
Hell Hole Dam is expected to spill in mid June.
There is considerable confusion about the boatable range in this reach. Given the small number of paddle trips and the lack of accurate flow information in the past, that confusion is to be expected. As flow information is provided, boaters will be able to explore the high and low ends of the boatable range. Some estimates of low, optimum and high flows were compiled in the PCWA licensing process.
Range Optimum400 to 1200 500-700400 to 3000 700-1,500
As of 2010 there is no online flow gauge information available for this reach. AW volunteers keep in contact with the dam operators and lobby them to report flows during spill periods. AW is working with PCWA to get real time flow information online from gauges below the dam and at Ellicotts Bridge. We also hope to get flow information for Rubicon above Ralston Afterbay. With this information boaters will be able to utilize boatable flows from rain and side streams as well as spill from Hell Hole Reservoir.
Hell Hole daily storage is reported online. Presently, there are no gates on the spillway, so spill begins to occur when storage is above 207,500 acre/feet. Spill gets into boatable range when storage is around 208,500 acre/feet. PCWA has plans to add bladder gates in the spillway which would increase reservoir capacity to 215,000 acer/feet. Loon Lake Hourly Storage and Elevation is also reported online. This reservoir will spill when storage is above 76,500 acre/feet. Spill will travel down Gerle Creek to the SF Rubicon and on to the main Rubicon above Ellicot Bridge.
The Rubicon seldom has boatable flows because there are several different reservoirs belonging to different projects that each take water out of the Rubicon basin and send it to the SF or MF American rivers.
USGS-schematic of Rubicon & MF American pdf
Flows in the upper Rubicon drainage are diverted at Rubicon Reservoir, to Buck Island Reservoir, to Loon Lake Reservoir. The water is eventually sent through Robbs Peak Powerplant into the SF American drainage. Rubicon Reservoir and Buck Island Reservoir are capable of diverting up to 1,000 cfs to Loon Reservoir. The South Fork Rubicon River has a diversion dam upstream of Gerle Creek that sends flows to the Robbs Peak Powerplant. Sacramento Municipal Utility District (SMUD) operates these reservoirs. FERC project #2101. Upper American River Project schematic. pdf
Hell Hole Reservoir captures any flow remaining in the Rubicon and sends most of it over to the MF American. With a capacity of 207,000 acre feet, Hell Hole is a fairly large reservoir. It not only captures Rubicon flows but also receives flows from French Meadows Reservoir on the MF American River through the French Meadows powerplant. Flows are sent back to the MF American through a tunnel to the Middle Fork Powerplant. Hell Hole is part of a PCWA project, FERC project #2079.
Three small tributaries below Hell Hole reservoir are also diverted. North and South forks of Long Creek are both diverted by PG&E to the Middle Fork Powerplant tunnel. It also appears that some water is diverted from the SF Rubicon into Pilot Creek to Stumpy Meadows Lake, then diverted to Georgetown Irrigation district. Up to 60 cfs can be diverted from Pilot Creek below Stumpy Meadows Lake. It is unclear how much flow can be diverted from the SF Rubicon into Pilot Creek, or if this diversion is still in operation.
Historical records are available for many locations within the Rubicon basin. Rubicon below Hell Hole Dam Spills 3 or 4 years out of 10. Middle Fork Powerhouse Receives water from Hell Hole. Maximum capacity about 950 cfs. French Meadows Powerplant delivers up to 400 cfs from MF American to Hell Hole reservoir. Middle Fork American below French Meadow dam shows how often French Meadow spills.
South Fork Rubicon below Gerle Creek Diversion of up to 1,440 cfs. High flows occur seldom. They appear and dissappear so quickly that it appears very difficult to utilize them.
Rubicon above Rubicon Reservoir very poor records Rubicon below Rubicon Reservoir measures minimum releases only. Spillway flows are not measured. Little Rubicon below Buck Island Dam measures minimum releases only. Spillway flows are not measured. Buck-Loon diversion tunnel Capacity approximately 1,000 cfs. Robbs Peak Powerhouse Receives all diverted flows from upper reservoirs. Maximum capacity about 1,200 cfs. Pilot Creek below Diversion shows annual peak flows. Daily flow information is available in the USGS Annual Water Data Reports such as the 2006 report pdf Pilot Creek can add big flows but it enters the Rubicon near the very end of this reach. Flows in this tributary can be surprisingly high compared to the SF Rubicon.
NF Long Creek Daily records below the diversion for some periods only. High flows do not seem to be recorded. SF Long Creek Daily records below the diversion for some periods only. High flows do not seem to be recorded.
We have no additional detail on this route.
Use the map below to calculate how
to arrive to the main town from your zipcode.
Common Portage #5
2nd Bedrock Gorge ~1100 cfs
Common Portage #3
Common Portage #2
Big Bedrock on the Rubicon
Water in the Rubicon, Coming Soon
Rubicon River, Low Water
Sticky Falls, Rubicon River
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Middle Fork American, Pit River, Tuolumne flow updates
Several utilities periodically report flows to us for river segments that do not have online gauges. They sometimes make estimates of upcoming flows based on predicted weather conditions. We will try to update that information to this news article when we receive the new information.
Middle Fork American RiverBlw French Meadows: 220 cfsDuncan Creek blw Diversion: 165Abv Middle Fork Interbay: 500 cfsBlw Middle Fork Interbay: 525 cfs (estimate) Abv Ralston Afterbay: 600 cfsRubicon RiverHell Hole Elevation: 4631.68 ftEllicotts: 1610 cfsAbv Ralston Afterbay: 1990 cfsNorth Fork of the Middle Fork American: 540 cfs
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