2005 Trinity River
Flow Release
from Lewiston Dam*
|
Date |
Flow in cfs (cubic feet/second) |
|
Jan 1-April 21 |
300 |
|
April 22-28 |
500 |
|
April 29 |
2000 |
|
April 30-May 5 |
2500 |
|
May 6-7 |
4500 |
|
May 8-9 |
6000 |
|
May 10-13 |
7000 |
|
May 14-15 |
6000 |
|
May 16 |
5600 |
|
May 17 |
5200 |
|
May 18 |
4800 |
|
May 19-20 |
4500 |
|
May 21 |
4200 |
|
May 22 |
3900 |
|
May 23 |
3600 |
|
May 24 |
3300 |
|
May 25 |
3000 |
|
May 26-7 |
2800 |
|
May 28-29 |
2600 |
|
May 30 |
2500 |
|
May 31-June 1 |
2400 |
|
June 2-3 |
2300 |
|
June 4-5 |
2200 |
|
June 6-7 |
2100 |
|
June 8-July 9 |
2000 |
|
July 10 |
1700 |
|
July 11 |
1500 |
|
July 12 |
1350 |
|
July13 |
1200 |
|
July 14 |
1050 |
|
July 15 |
950 |
|
July 16 |
850 |
|
July 17 |
750 |
|
July 18 |
675 |
|
July 19 |
600 |
|
July 20 |
550 |
|
July 21 |
500 |
|
July 22-Aug 28 |
450 |
|
Aug 29 |
1650** |
|
Aug 30 |
1650** |
|
Aug 31-Oct 15 |
450 |
|
Oct. 16-Dec 31 |
300 |
*Based on Normal Water Year
647af
**Hoopa Boat
Dance
The flow on the Trinity River near Big Flat is a combination of the dam release flows, listed above, plus tributaries between the dam and whitewater runs. In the Springtime, there is significant tributary input, and later in the summer, the flow is mostly dam release.
To see actual flow nearby,
look at the guage at Cedar Flat which is found at http://cdec.water.ca.gov/cgi-progs/queryLonger?9272
You can anticipate likely flows from the dam release schedule. The tributary
input in early June is highly variable, but might be 1000 to 2000 cubic feet
per second (cfs) higher. In early July, add 300-600 cfs. In early August add
150-300, and 100-200 at the beginning of September. These are only estimates,
and can vary greatly depending on snowpack, rain, and temperatures.
What
this Means
Below 450 cfs. This is a flow we only see in the
fall after mid October. Challenging, but possible in a full-sized raft. The
river is serene at these levels, with Autumn colors and Salmon in the river.
450-1000 cfs. Lower technical
flows. Warm summertime waters at this level are popular for rafting.
Maneuvering between rocks is engaging and required. Hell Hole becomes a wet,
steep drop.
1000-2500 cfs. Medium-low
flows. Most rocks remain submerged. A wet ride, very fun. Leisurely, effortless
float through pools.
2500-4000 cfs. Medium Flows.
Lots of splash. Plenty of current, but not so fast as Big Water.
4000-6000 cfs. Big Water, Big
Waves Big Fun. Water is somewhat in the trees along the edges, fast. It is
reasonable for good swimmers with a guide.
Flows over 7500 cfs. These
are upper levels for rafting. Water is fast and in the trees along the bank.
Must be strong swimmer, wearing wet or drysuits. Pigeon Pt. to Big Flat takes
less than an hour.