Drought conditions ravage Missouri River basin

Drought conditions ravage Missouri River basin Drought conditions continue to ravage much of the Missouri River basin. October's runoff above Sioux City, IA, was only 61 percent of normal.

"Releases from Gavins Point Dam were set as high as 31,000 cubic feet per second (cfs) during October 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 continues to be very dry. Inflows into Fort Peck and Garrison were only 55 and 78 percent of normal, respectively."

October's runoff totaled 727,000 acre-feet.

"Our runoff forecast for this year has been reduced to 16.1 million acre feet (MAF)," said Cieslik.

Annual runoff is normally 25.2 MAF.

Gavins Point releases averaged 29,500 cfs in October, compared to the average of 37,100 cfs. 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; Mouth near St. Louis, MO, Dec. 1.

"Releases will be reduced 3,000 cfs a day beginning around Nov. 24 until a release of 13,000 cfs is reached in late November. Temporary release increases could be necessary during severe cold weather to prevent excessively low stages caused by ice build-ups. Moderate temperatures could allow releases to be set lower than 13,000 cfs.

System storage ended October at 44.1 MAF, down 1.4 MAF during the month. Last year at this time it was 50.4 MAF.

"Drought has cut the amount of water stored in the reservoirs to 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 1207.8 feet above mean sea level (msl), will gradually lower to elevation 1207.5 feet msl during November. It will remain at that level through the winter.

Fort Randall releases averaged 29,400 cfs in October. They will range from 25,000 to 27,000 cfs during most of November as needed to maintain the level of Lewis and Clark Lake. Releases will gradually be reduced to 12,000 cfs as the navigation season ends. Lake Francis Case ended the month at elevation 1338.2 feet msl. It will remain near that elevation until Nov. 8, and then continue its annual drawdown, reaching 1335 feet msl by mid-month. It will begin refilling in late November.

Lake Oahe dropped one foot during October, ending the month at elevation 1585.1 feet msl. It will drop one foot during November, ending the month 18 feet below normal. The lake is 16 feet lower than last year at this time.

Garrison releases averaged 13,800 cfs during October. In early November, releases were increased from 14,000 cfs to 18,000 cfs, where they will remain through the month. Lake Sakakawea ended October at 1826.6 feet msl. It will drop nearly two feet in November, ending the month 13 feet below normal. The lake is 5 feet lower than last year at this time.

Fort Peck releases averaged 4,700 cfs during October. They will remain near 5,000 cfs for most of November, before being increased to 10,000 cfs in early December. The lake ended the month at elevation 2217.3 feet msl. It will remain near its current elevation during November. Last year at this time it was 3 feet higher.

The six main stem powerplants generated 614 million kilowatt hours (kWh) of electricity in October, 69 percent of normal. Given the forecasted inflow this year, energy production should be 7.5 billion kWh compared to a normal of 10.1 billion kWh.

Bookmark the permalink.

Leave a Reply

Your email address will not be published. Required fields are marked *

You may use these HTML tags and attributes: <a href="" title=""> <abbr title=""> <acronym title=""> <b> <blockquote cite=""> <cite> <code> <del datetime=""> <em> <i> <q cite=""> <strike> <strong>