Boat ramps on Brownlee Reservoir usually get harder to use from late October on, and the reason is about 9,000 cubic feet per second of water leaving Hells Canyon Dam. The level of the reservoir west of Cambridge depends partly on fall Chinook salmon spawning below the dams. That makes the choice of ramp the main decision for a late-season trip.
Idaho Power's Fall Chinook Flow Program runs from October through December. During that time the utility holds the release from the Hells Canyon Complex between 8,500 and 13,000 cfs until the salmon eggs hatch. The utility says that to do this it sometimes lowers Brownlee so the reservoir can take in higher inflows while the outflow stays steady. It also says the lower water limits how much power the three dams can generate, so it may buy electricity from other sources.
The arithmetic behind the fall draw
On its water information FAQ, Idaho Power explains why it keeps the flow steady. Biologists have found 9,000 cfs to be the best flow for keeping the salmon nests, called redds, underwater until the hatchlings leave the following May. If the winter-to-spring minimum is set too high and a dry spring follows, there may not be enough water to keep the redds covered. The timing problem is described in the utility's own words:
"However, from late October through early December when we would like to have a 9,000 cfs outflow from Hells Canyon, inflows are usually higher than 9,000. Since inflows are greater than outflows, we must reduce the water level at Brownlee Reservoir beforehand to create space to store the excess water."
Brownlee is the only reservoir in the system that can do this job. Idaho Power calls it its only facility big enough to store water for more than a few hours, and it says the generators run more efficiently when the reservoir is full. The utility would rather keep the reservoir high. The fall draw happens because the salmon flow below Hells Canyon Dam leaves little choice.
Fall isn't the only time the water drops. In spring the U.S. Army Corps of Engineers requires releases nearly every year to make room for runoff and protect the Portland area from flooding. In June the operating plan aims to keep Brownlee within its top 10 feet while smallmouth and other bass are nesting. The fall draw follows its own calendar, and it begins right as the summer season ends.
The calendar around the fall draw
The draw is one date among several that shape a trip to Brownlee between summer and next spring:
| When | What changes | Source |
|---|---|---|
| July 20, 2026 | Harmful algae advisory issued for Brownlee and Hells Canyon reservoirs | Idaho DHW |
| October 7, 2026 | Latest Oregon State Marine Board ramp depths for the Oregon shore | Oregon State Marine Board |
| October 15 | Campsite water shut off at Idaho Power parks, or sooner if it turns cold | Idaho Power parks FAQ |
| Late October to early December | Brownlee lowered ahead of high inflows to protect fall Chinook flows | Idaho Power water FAQ |
| March 15 | Water turned back on at the Hells Canyon parks | Idaho Power parks FAQ |
The parks stay open. Idaho Power says its parks and campgrounds are open all year, though some services may not be available and some areas may be restricted. After October 15, plan on bringing your own water for camp. The rest of the trip mostly comes down to which ramp you pick.
Which ramps were built for a falling pool
When Brownlee is full, its surface sits at 2,077 feet above sea level. An older Idaho Power relicensing report on recreation, revised in 2003, lists the design limits for the ramps on the Idaho side. These are engineering figures, not current conditions, but they show how far each ramp was meant to reach.
- Woodhead Park, 23 miles northwest of Cambridge on Highway 71. According to that report, the four-lane ramp works down to 2,022 feet, or 55 feet below full pool. The original one-lane ramp was built for maximum drawdown and works down to 1,976 feet, which is 101 feet below full. Woodhead also has 118 RV hookups and 15 tent sites.
- McCormick Park, 29 miles northwest of Cambridge, with 28 RV sites and eight tent sites. Idaho Power's parks listing shows a boat ramp and docks there. The older report describes a concrete ramp but gives no low-water limit for it.
- Hewitt Park, on the Oregon side. Its main ramp was extended 100 feet, which moved its usable limit from 2,048.5 feet down to 2,036.5 feet. That still leaves it working only to about 40 feet below full, much less than Woodhead's original ramp.
The Oregon shore already showed the problem in the Oregon State Marine Board's October 7 access report. That day Moonshine Mine had about 36 feet of water over the bottom of its ramp, Farewell Bend 19, Hewitt's low-water ramp about 18, and Holcomb Park about 9. Spring Recreation Site had 1 foot, and its campground was closed. The BLM's Spring Recreation Site page says the day-use area and ramp are open, the campground stays closed until suppression repairs are done, and the ramp may close when the reservoir is low. A ramp with 1 foot of water over its bottom before the late-October draw starts has almost nothing left to lose.
The upper end of the reservoir changes differently. Idaho Power notes that Farewell Bend and Steck Park are nearly 50 miles upstream of Brownlee Dam. When the reservoir falls below 2,055 feet, its water no longer backs up that far, and conditions there depend on river flow, not the reservoir. Idaho Power's recreation updates page names Hewitt Park and Farewell Bend as the ramps most likely to be affected when unsettled weather changes inflows quickly.
Down at Oxbow, Idaho Power closed the ramp September 1 and 2 for repairs meant to make it more usable at lower water. The spillway area at Oxbow Dam is closed to the public. The Hells Canyon Creek Visitors Center keeps hours based on staffing, so call 541-785-3395 before driving that far.
The algae advisory has not been lifted
The July 20 advisory still applies to anyone heading to the water this fall. The Idaho Department of Health and Welfare advisory for Brownlee and Hells Canyon reservoirs was issued after samples showed high levels of toxin-producing cyanobacteria. It came two weeks after a separate July 7 advisory for Crane Creek Reservoir, south of Cambridge. In mid-October, the Oregon Health Authority's advisory table still listed Brownlee and Hells Canyon as "Advisory in effect." Idaho's health advisory list showed no later notice for Brownlee as of October 9.
While the advisory is in effect, DHW asks people near these reservoirs to:
- Avoid swimming, wading, or other contact with the water, and keep children from drinking it or getting it on them.
- Keep pets and livestock out of the water, and rinse skin, hide, or fur with clean water right away if they get in.
- Never drink or cook with the water. Boiling or filtering does not remove the toxins.
- Wash hands thoroughly in clean water after handling fish or anything else that came out of the reservoir.
The advisory also covers eating fish. It advises washing and filleting the catch and removing the fat, skin, and organs, and it notes that cyanotoxins can build up in fish.
Fishing after the weather cools
The Oregon Department of Fish and Wildlife's Snake Zone report for October 8 lists trout, perch, crappie, bass, catfish, and sturgeon in Brownlee, Oxbow, and Hells Canyon reservoirs. It says warmwater fishing can slow down in hot weather and anglers may do better once cool fall weather returns. Idaho Power's FAQ says Brownlee's crappie are hurt more by high flows, because the fish stay mostly in the middle of the reservoir and strong current in high-water years carries them downstream.
Those fish are spread along a reservoir whose level can change daily. Idaho Power says flow changes for salmon are usually requested when the cooperating agencies see a need, so the timing isn't always known ahead of time. Before towing a boat west on Highway 71, check two things. One is the Brownlee elevation dashboard. The other is Idaho Power's toll-free recreation line at 1-800-422-3143. Compare the number you get with the ramp limits above. If the reservoir is well below 2,036 feet, Hewitt is probably past its design limit. Woodhead's original ramp was built for water much lower than that.
If you want to plan ahead for next season, Idaho Power takes reservations for Woodhead and McCormick all year, up to nine months ahead, and they must be made before midnight Mountain Time the day before you arrive. Campsite water goes back on at the Hells Canyon parks March 15.
If you're considering acreage or a cabin near Highway 71 because you want to be close to the water, I'm glad to talk through how Brownlee changes from season to season and what that means for a property. Creed Noah Real Estate Company has worked in this part of Washington County since 1995. Let's Connect.
