Click to hear KMZU’s Kristie Cross talk to U. S. Army Corps of Engineers spokesperson Monique Farmer:
Although we have received some rain and snowfall in recent months, a good portion of the midwest continues to remain dry. Farmer said the conditions are impacting the river. “We will be beginning the spring just a little over eight million acre feet below the base of our annual flood control pool,” said Farmer,” In times of drought, we like to refer to that as the carryover, multiple use zone because it acts like a bank account that we use for storage to be able to serve all eight of our congressionally authorized purposes through a drought.”
According to the corps, more than 20 percent of the storage was used to serve those project purposes in 2012. In order to conserve water, releases from the Gavins Point Dam are at the lowest level possible this winter. While barges may have to carry lighter loads, the river is expected to carry a full-length nagivation season from April to December.
The conditions in the area are impacting the winter releases on the Missouri River. According to the Corps, releases at Gavins Point Dam usually average between twelve and seventeen cubic feet per second. Farmer said there have been some adjustments during recent months. “This year, our target was to get down to twelve cubic feet per second,” said Farmer,” However, in working with some of the municipalities and water supply users who have intakes in the water, we experienced some difficulty as soon as we got just below 14 cubic feet per second. Therefore, our winter release rate is going to remain at 14 cubic feet per second so we can allow those folks to be able to continue to remain operable.”
The corp will continue to monitor river levels and make adjustments as necessary if the dry weather persists. Monthly recorded conference calls regarding current conditions are available to the public at http://itunes.apple.com/podcast/missouri-river-basin-water/id508457675.
With no relief in sight from the ongoing drought, the Corps is predicting runoff into the mainstem reservoir system will remain below normal, at least through spring.
The National Drought Mitigation Center indicates that with the exception of portions of Montana and North Dakota, much of the Missouri River basin is suffering from severe to exceptional drought conditions. The worst drought conditions exist over much of Wyoming, South Dakota, Nebraska, Kansas and northwest Iowa.
Based on the current soil moisture and snowpack conditions, 2013 runoff in the Missouri River basin above Sioux City, Iowa is forecast to be 20.5 million acre feet, 82 percent of normal. Runoff during 2012 totaled 19.8 million acre feet, 80 percent of normal.
At the start of the 2013 runoff season, which typically begins around March 1, the total volume of water stored in the mainstem reservoir system is expected to be 8.5 million acre feet below the top of the carryover multiple use zone. The carryover multiple use zone, which is often referred to as the reservoir system’s “bank account for drought,” contains 38.9 MAF of water when full. It’s designed to provide service to the eight congressionally authorized purposes, though at reduced levels, through a 12-year drought like that of the 1930s and early 1940s. Those purposes are: flood control, navigation, water supply, irrigation, hydropower, recreation, water quality control, and fish and wildlife.
More than 20 percent of the drought storage was used to serve the authorized project purposes during 2012. Reducing service to the authorized purposes in future years will conserve water in the reservoir system if the drought persists. Examples of reductions in services may include reduced hydropower generation, reduced flow support to navigation and lower lake levels to name a few. Flood control is the only authorized purpose that is enhanced when there is less water in the system of dams along the Missouri River.
The primary drought conservation measures outlined in the Master Manual include reducing winter releases and flow support for navigation.
In order to conserve water in the Corps’ mainstem reservoir system, releases from Gavins Point Dam are being scheduled at the lowest level possible this winter while still serving the needs of the municipal, industrial and powerplant water intakes along the lower Missouri river.
Releases from Gavins Point were temporarily increased from 14,000 cfs to 18,000 cfs in mid-December to ensure intakes would remain operational when much colder temperatures moved into the region building ice on the river. “Releases were increased to replace water that was being locked up in river ice. Now that the ice is no longer building, the additional releases are no longer necessary,” said Jody Farhat, Chief of the Northwestern Water Management Division.
“Weather and river conditions will continue to be monitored, and additional release increases may be necessary if extremely cold temperatures return,” said Farhat.
Navigation flow support for the first half of the 2013 Missouri River navigation season will likely be set at or near minimum levels based on the March 15 system storage check. Full service navigation flows are designed to provide a 9 feet deep by 300 feet wide navigation channel from Sioux City to the mouth near St. Louis, Mo.; minimum service flow support provides an 8 feet deep by 200 feet wide channel. Flow support for the second half of the navigation season and the season length are based on the July 1 system storage check. A full-length navigation season extends from April 1 to Dec. 1 at the mouth.
Mountain snowpack is currently tracking near normal in the reach above Fort Peck (101 percent) and slightly below normal in the reach between the Fort Peck and Garrison dams (91 percent of normal). Typically 45 percent of the peak mountain snowpack accumulation has occurred by Jan. 1.
Snowpack on the plains is generally light with most areas reporting less than an inch of water equivalent currently.
“The Corps will continue to monitor both the plains and mountain snowpack throughout the winter, as well as basin soil conditions to fine tune the regulation of the reservoir system based on the most up to date information,” said Farhat.
View mountain snowpack graphic here: http://www.nwd-mr.usace.army.mil/rcc/reports/snow.pdf
Final 2012-2013 Annual Operating Plan released
After reviewing comments received on the draft, the Missouri River Basin Water Management Office developed and released the Final Annual Operating Plan for the Missouri River Basin for 2012-2013. The plan is posted at: http://www.nwd-mr.usace.army.mil/rcc/aop.html
Monthly Water Management Conference Calls begin for 2013
The Corps hosted its first conference call of 2013 Tuesday, Jan. 8 to keep basin stakeholders informed about reservoir operations, basin forecasts and weather conditions. The call is intended for Congressional delegations, Tribes, and state, county and local government officials. It was recorded in its entirety and will be made available as a free podcast in iTunes. Subscribe at: http://itunes.apple.com/podcast/missouri-river-basin-water/id508457675. Or, simply run a search for Missouri River Basin Water Management in iTunes. The audio file will also be posted to the Omaha District’s Facebook page following each call.
This year’s calls are planned for the second Tuesday of each month and are expected to run through July. Additional calls will be scheduled if conditions warrant.
Gavins Point releases averaged 16,300 cfs during the month of December. Releases are gradually being returned to the winter release rate of 14,000 cfs. The reservoir behind Gavins Point dam ended December at elevation 1207.7 feet. It is expected to remain near that level this month.
Fort Randall releases averaged 14,200 cfs during the month of December. Releases are expected to average 13,300 this month, and will be adjusted as necessary to maintain the elevation at Gavins Point. The reservoir ended December at elevation 1340 feet, down 0.2 foot from the previous month. It is expected to rise 4.8 feet by the end of the January. The refill of the reservoir is designed to provide increased winter hydropower generation at Oahe and Big Bend.
Big Bend releases averaged 12,900 cfs during the month of December. They are expected to average 18,100 cfs this month. The reservoir will remain near its normal elevation of 1420 feet this month.
Oahe releases averaged 14,700 cfs during the month of December. Releases are expected to average 17,400 cfs this month. The reservoir ended December at elevation 1593.6 feet, up 0.3 foot during the month. The reservoir is expected to climb one foot during the month of January.
Garrison releases averaged 17,400 cfs in December. Releases were reduced from 22,000 cfs to 16,000 cfs near mid-December to prepare for the river freeze-in. Releases are gradually being increased and are expected to reach the winter release rate of 23,000 cfs by mid-January. The reservoir ended the month at elevation 1829.4 feet, down 0.9 foot from the previous month. It is expected to decline about a foot during January.
Fort Peck releases averaged 11,100 cfs in December. Releases were increased to 12,500 cfs in early January to better balance storage in the upper three reservoirs and to provide additional winter hydropower. The reservoir ended the month at elevation 2226.1 feet, down 2.2 feet from the previous month. It is forecast to remain near that level this month.
The forecast reservoir releases and elevations discussed above should not be assumed to be definitive. Additional precipitation or lack of precipitation in the basin could cause adjustments to the reservoir release rates.
The six mainstem power plants generated 569 million kilowatt hours of electricity in December. Typical power generation for the month of December is 696 million kWh. The power plants are projected to generate 8 billion kWh of electricity this year, compared to the normal of 10 billion kWh.
To view the detailed three-week release forecast for the mainstem dams, go to: http://www.nwd-mr.usace.army.mil/rcc/reports/twout.html.
MISSOURI RIVER MAIN STEM RESERVOIR DATA
|Reservoir||Pool Elevation (ft msl)||Water in Storage – 1,000 acre-feet|
|On Nov. 30||Change in Nov.||On Nov. 30||% of 1967-2011 Average||Change in Nov.|
WATER RELEASES AND ENERGY GENERATION FOR NOVEMBER
|Average Release in 1,000 cfs||Releases in 1,000 af||Generation in 1,000 MWh|