Dry conditions reduce Missouri River flows

Dry conditions reduce Missouri River flows Dry conditions across much of the Missouri River basin showed no signs of improving in September. Runoff above Sioux City, IA, was only 65 percent of normal.

"Releases from Gavins Point Dam were set as high as 31,000 cubic feet per second (cfs) during September to meet our minimum service flow target of 35,000 cfs at Kansas City. There is very little tributary flow contribution below Gavins Point," said Larry Cieslik, chief of the Missouri River Basin Water Management Division in Omaha. "The upper part of the basin also continues to be dry. Fort Peck and Garrison inflows were only 69 and 38 percent of normal respectively."

September's runoff totaled 700,000 acre-feet. "Our runoff forecast above Sioux City for 2002 has been reduced to 16.5 million acre feet (MAF)," said Cieslik. Annual runoff is normally 25.2 MAF.

Gavins Point releases averaged 29,700 cfs in September, compared to the average of 37,300 cfs. They will range from 27,000 cfs to 31,000 cfs in October as necessary to meet navigation targets. As previously announced, the navigation season will end on the normal date of Dec. 1.

Flow support for the 2002 commercial navigation season will end as follows: Sioux City, IA, Nov. 22; Omaha, NE, Nov. 24; Nebraska City, NE, Nov. 25; Kansas City, MO, Nov. 27; and Mouth near St. Louis, MO, Dec. 1.

The 2002 Draft Annual Operating Plan (AOP) for the operation of the Missouri River Mainstem Reservoir System is available for review and comment. The draft is available at http://www.nwd-mr.usace.army.mil/rcc/index.html or by calling the Water Management office at (402) 697-2675. Three public meetings to review the draft 2002-2003 AOP will be held Oct. 15, 16, and 17. The first will be Oct. 15 in Bismarck, ND, at 7 p.m. at the Doublewood Inn, 1400 E. Interchange Ave. The second will be Oct. 16 in Omaha, NE, at 6 p.m. in the Northwestern Division office, 12565 W. Center Road. The third will be Oct. 17 in Jefferson City, MO, at 7 p.m. at the Ramada Inn and Convention Center, 1510 Jefferson St.

System storage ended the month at 45.5 MAF, down 1.4 MAF during the month. Last year at this time it was 50.4 MAF. "The amount of water stored in the reservoirs is more than 13 MAF lower than average, putting the three largest main stem lakes 13-18 feet below normal," said Cieslik.

Lewis and Clark Lake, which is near elevation 1207 feet above mean sea level (msl), will gradually rise to elevation 1207.5 feet msl during October.

Fort Randall releases averaged 30,000 cfs in September. They will range from 28,000 to 32,000 cfs in October as needed to maintain Lewis and Clark near its desired elevation. Lake Francis Case ended September at elevation 1350.7 feet msl. It will continue its fall drawdown during October. As previously announced, the accelerated drawdown schedule this year will drop the pool to approximately elevation 1335 feet msl by early November, where it will remain through mid-month. It will begin refilling in early December.

Lake Oahe dropped nearly 2 feet during September, ending the month at elevation 1586.4 feet msl. It will remain near its current elevation during October, ending the month nearly 16 feet below normal. The lake is 17 feet lower than last year at this time.

Garrison releases averaged 17,500 cfs during September. They were reduced from 21,000 cfs to 14,000 cfs during the month. They will remain at that rate through November. Lake Sakakawea ended September at 1827.5 feet msl. It will drop one foot in October, ending the month 13 feet below normal. The lake is 4 feet lower than last year at this time.

Fort Peck releases averaged 6,800 cfs during September. They were cut from 9,000 cfs to 5,000 cfs during the month where they will remain through November. The lake ended the month at elevation 2217.6 feet msl. It will remain near its current elevation during October. Last year at this time it was 3 feet higher.

The six main stem powerplants generated 746 million kilowatt hours (kWh) of electricity in September, 70 percent of normal.

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