News Release
| Release Number: | 06-009 |
| Dated: | 5/5/2006 |
| Contact: | Paul T Johnston, 402-697-2552 |
OMAHA – Melting of some low-level mountain snow and welcome rain raised Missouri River reservoir levels 0.5 to 2 feet during April. However, anticipated runoff for the year remains at only 83 percent of normal.
“The overall mountain snowpack peaked around April 15 very near its normal level,” said Larry Cieslik, Chief of the Water Management office here. It peaked at 108 percent of normal in the reach above Fort Peck and 88 percent in the reach from Fort Peck to Garrison, essentially the Yellowstone River basin.
There is currently 38 million acre feet (MAF) stored in the reservoirs, 19 MAF below normal. Runoff for the year is forecasted to be 21 MAF, 83 percent of normal. Normal runoff is 25.2 MAF. System storage at the end of May is forecast to increase to 38.7 MAF.
River flows to support navigation will be at minimum service levels. The season length is anticipated to be shortened by 31 to 55 days, depending on runoff in the coming months. The final decision will be based on the water-in-storage check on July 1.
The Corps will strive to provide rising levels in the upper three reservoirs during their annual forage fish spawns. However, this may not be possible at all three reservoirs under low runoff conditions. If rising pools cannot be provided in all three, releases will be adjusted to provide a steady to rising level in Garrison reservoir during May. The ability to provide such conditions depends on the volume, timing and distribution of the runoff from melting snow in the mountains of Montana and Wyoming.
Gavins Point reservoir will fall two feet to near elevation 1206 feet above mean sea level (msl) in May. Releases averaged 14,300 cubic feet per second (cfs) in April compared to the long-term average of 26,200 cfs. They will average 21,300 cfs in May, 8,000 cfs below the average of 29,600 cfs.
Fort Randall releases averaged 11,400 cfs in April. They were adjusted as necessary in April to maintain Gavins Point reservoir near its desired elevation. The reservoir ended the month at 1357.3 feet. It will fall two feet in May, ending the month near elevation 1355 feet msl.
Big Bend reservoir will remain in its normal range of 1420 to 1421 feet. Releases will be adjusted to meet hydropower needs.
Oahe reservoir rose more than half a foot in April, ending the month at elevation 1577.4 feet msl. It is expected to climb nearly two feet in May, ending the month at 1579.1, about 27 feet below normal. The reservoir is 2.7 feet higher than it was last year at this time.
Garrison releases averaged 13,800 cfs during April, compared to the long-term average of 19,500 cfs. They are expected to average16, 500 cfs in May, compared to the 21,600 cfs average. Garrison reservoir rose nearly 2 feet in April, ending the month at 1812.5 feet msl. It will rise more than 1.5 feet to 1814 feet in May, ending 21.6 feet below normal. The reservoir is almost 6 feet higher than last year at this time.
Fort Peck releases averaged 6,500 cfs in April, compared to the long-term average of 7,700 cfs. They will average 8,000 cfs in May. The reservoir rose more than 2 feet in April, ending the month at elevation 2203.6 feet msl. It will continue to climb in May, ending the month at elevation 2205.4, about 27 feet below normal. It is 5 feet higher than last year at this time.
The six main stem power plants generated 413 million kilowatt hours (kWh) of electricity in April, the third lowest April generation on record and only 57 percent of normal because of lower pool levels and reduced releases from the dams. The forecast for energy production in 2006 is 6.0 billion kWh, compared to the average of 10 billion kWh.
Daily and forecasted reservoir and river information is available to the public on the Water Management section of the Northwestern Division homepage: www.nwd.usace.army.mil.
|
|
Pool Elevation (ft msl) |
Water in Storage - 1,000 acre-feet |
|||
|
|
On Apr 30 |
Change in Apr |
On Apr 30 |
% of 1967-2005 Average |
Change in Apr |
|
|
2203.6 |
+2.1 |
9,540 |
65 |
+318 |
|
Garrison |
1812.5 |
+1.8 |
11,460 |
66 |
+384 |
|
Oahe |
1577.4 |
+0.7 |
11,150 |
60 |
+126 |
|
|
1420.7 |
+0.4 |
1,661 |
96 |
+23 |
|
|
1357.3 |
+2.3 |
3,726 |
95 |
+193 |
|
Gavins Point |
1208.1 |
+1.9 |
411 |
110 |
+48 |
|
|
|
|
37,948 |
67 |
+1,092 |
WATER RELEASES AND ENERGY GENERATION FOR APRIL
|
|
Average Release in 1,000 cfs |
Releases in 1,000 af |
Generation in 1,000 MWh |
|
|
6.5 |
389 |
51 |
|
Garrison |
13.8 |
819 |
105 |
|
Oahe |
13.3 |
789 |
101 |
|
|
12.1 |
721 |
42 |
|
|
11.4 |
681 |
75 |
|
Gavins Point |
14.3 |
848 |
39 |
|
|
|
|
413 |