Drought conditions persist in Missouri basin

Drought conditions persist in Missouri basin
Runoff above Sioux City, IA, in August was 800,000 acre feet, only 59 percent of normal.

"The Platte River in Nebraska continues to provide good flows, but most of the other downstream tributaries continue to fall," said Larry Cieslik, chief of the Water Management office in Omaha.

Releases from the reservoirs will be limited to the rate necessary to maintain minimum target flows. They will be reduced to near 9,000 cubic feet per second (cfs) in October with the closing of the commercial navigation season.

The current runoff forecast for 2005 is 20 million acre feet (MAF), compared to a normal of 25.2 MAF. As previously announced, the navigation season will be shortened 48 days, the greatest shortening on record.

This was another successful nesting season for the endangered least terns and threatened piping plovers. Fledge ratio goals set by the U.S. Fish and Wildlife Service were attained for both species.

"A record number of adult terns and plovers were counted this year," added Cieslik.

System storage ended August at 37.3 MAF. Last year at this time it was 36.6 MAF. The amount of water currently stored in the reservoirs is nearly 21 MAF below average.

The draft 2005-2006 Annual Operating Plan is slated for release in early October for public review and comment. A series of public meetings at various locations along the river will be conducted in November. Dates and locations have not been selected yet.

Gavins Point reservoir will remain near elevation 1207 feet above mean sea level (msl) during September. Releases averaged only 23,400 cfs in August compared to the normal 35,700 cfs. They will range from 25,000 cfs to 27,000 cfs through the month. Early in the first week of October, releases will be reduced by 3,000 cfs per day until they reach 10,000 cfs. That rate will be held for

five days and further reduced to the non-navigation fall rate of 9,000 cfs where they will be held until late November or early December.

Fort Randall releases averaged 23,100 cfs in August. They will range from 24,000 cfs to 26,000 cfs in September as needed to maintain Gavins Point reservoir near its desired elevation.

Fort Randall reservoir ended August at 1353.6 feet msl. Its annual Fall drawdown is now underway. It will end the month near elevation 1343 feet msl. The reservoir will end October near its normal fall elevation of 1337 feet msl. The drawdown is occurring sooner than in previous years due to the reduced releases as flow support for the navigation season ends early next month.

Oahe reservoir dropped three feet during August, ending the month at elevation 1573.1 feet msl. It will rise more than a foot in September, ending the month 27 feet below average. The reservoir is a foot higher than it was last year at this time.

Garrison releases averaged 15,500 cfs during August, compared to the normal 24,800 cfs. They will average 15,500 cfs until Sept. 17, and then be reduced to 12,500 cfs. Garrison reservoir dropped 1.4 feet during August, ending the month at elevation 1815.8 feet msl. It will remain essentially level in September, ending the month 23 feet below average. The reservoir is 1.5 feet higher than last year at this time.

Fort Peck releases averaged 7,000 cfs in August, compared to the normal 10,300 cfs. They will remain near 7,000 cfs until the end of the irrigation season in mid-September when they will be reduced to 4,000 cfs. The reservoir dropped one foot during August, ending the month at elevation 2202.2 feet msl. It will remain essentially level during September, ending the month 32 feet below average. It is currently 1.3 feet higher than last year at this time.

The six main stem power plants generated 658 million kilowatt hours (kWh) of electricity in August, 63 percent of normal because of reduced releases from the dams. The forecast for 2005 energy production is 5.6 billion kWh, compared to a normal of 10 billion kWh.

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