Big Thompson, Colorado, US
|Usual Difficulty||III-IV+ (varies with level)|
|Avg. Gradient||107 fpm|
|Max Gradient||110 fpm|
|BIG THOMPSON RIVER BELOW LAKE ESTES|
|codwr-BTBLESCO0||250 - 900 cfs||III+||01h26m||22.9 cfs (too low)|
** September 2013 Colorado received record rainfall within a five day period that has now
completely changed the Big Thompson River. Lives were lost in this series of storms and the Big
Thompson River ran a course to redirect its flows and remove any roadways in the canyon.
This run is totally altered. The upper dam washed out and what used to be the crux rapid is
entirely different. The river will probably be closed to boating this summer as there lots
of big machines working in the river bed. Expect additional land sluff/slides and as of
April 2014 there's still a lot of debris (trees, culverts, junk, etc.) in the river bed.
This stuff will surely move when the water comes up.
The Big Thompson seldom has good flow (>400 cfs) but when this creek is pumping be ready for a
great ride. Sometimes people may put in below Idyllwilde Dam, but the more common putin is up
near Drake. Just be aware the dam is a killer, a mandatory portage. The run is steepest and most
difficult just downstream of the dam.
The Shuttle is simple as this run is all along Highway 34.
John Gross shared:
"1. The rating for the lower section should be III-IV+. This might be a very difficult class 3 run at lower water, but it always has class 4 consequences (it's 110 fpm, after all!). It's got a road-debris riverbed, and even at high water you're going to hit something if you flip. Above 500 or 600 - which we're seeing just about every year - swims are epic and often (usually) boats go more than a mile before they pin or you can get them out. It's not a beginner run at any level.
"2. River description:
For the lower run, a good putin is one mile above Drake - just below the end of the harder drops. Don't go too high. You'll immediately launch into a couple sections of very busy water around islands, followed by a small gorge and then an easier float into and past Drake. The most difficult rapid of the run is immediately below the Idyllwilde Dam, and first-timers will likely be very surprised at the velocity of water in this drop. Beware of a two offset holes just below this long rapid that are sticky at some levels. The culvert at Viestenz Smith Mountain Park has been replaced with a nice bridge, so enjoy the fun water through the park. A blind drop in a gorge below the park may warrant a quick scout; there's a fun left run at most levels, or on either side at higher water. Portage the lower diversion dam, where you may want to end the run if too much water is being removed.
"This run changes dramatically with water level. It's a boat-abusive class 3+ creek run at 300 cfs, and high-speed, action-packed 4+ at 800 with very few exposed rocks. At moderate to high water levels there are few pools and most eddies disappear - a solid roll is highly recommended. At higher levels, scout your take-out eddy at the canyon mouth (just above the lowhead dam) before launching."
For a hairy, trashy run, check out the upstream gnar-gnar section. You'll want to scout a bunch if you run that one.
Big Thompson, early June 2014 Update:
From Ian (Deepsouthpaddler): Ran it this weekend at 600-700. Last drop in gnar is horrible.
Strainer between gnar and drake rapid. Drake rapid has changed. Looks more serious. Put in below
drake big drop.
In general the run felt easier to me than the old run. The channel has been reshaped. Portage ugly culvert in Drake. The dam at Idlewild is gone. Some interesting new drops that were lower intensity than the old set below the dam.
The old takeout park was completely obliterated. The stretch just above that old park has some meaty holes that can induce swims.
From Suigereneris: Two culvert bridges unfortunately, one obvious and one indeed in Cedar Park but avoidable if you keep you eyes open as it is gray and seamlessly subtle at various flow levels. No tree at Cheery store. Upper section rocks as well.
|Mile||Rapid Name||Class||Features (Legend)|
|6.0||Viestenz-Smith Mountain Park||IV|
The most difficult rapid of the run is immediately below the Idyllwilde Dam, and first-timers will likely be very surprised at the velocity of water in this drop. Beware of a two offset holes just below this long rapid that are sticky at some levels.
A blind drop in a gorge below the park may warrant a quick scout; there's a fun left run at most levels, or on either side at higher water.
Portage the lower diversion dam, where you may want to end the run if too much water is being removed.