Drainage Monitoring and Evaluation
CORPS OF ENGINEERS OMAHA NE MISSOURI RIVER DIV
Pagination or Media Count:
Spring pulse releases for the benefit of the endangered pallid sturgeon were planned for March and May 2009 to mimic historic natural spring rises that occurred on the Missouri River before the closure of the main stem dams. The March spring pulse from Gavins Point Dam was not released in 2009 due to high downstream flows and the possibility of flow-limit violations. A 6.1 -kcfs May spring pulse was released in 2009. The May spring pulse was monitored at 44 sites along the Missouri River. Nineteen of these were interior-drainage sites that were monitored for possible socioeconomic impacts to landowners. Socioeconomic impacts include gate closures, pumping, and overbank flooding. To help identify socioeconomic impacts, berm and field elevations were surveyed near the installed gages in March 2009 to better characterize possible overbank flooding. The location of the created spring pulse in the record was determined through the use of travel times from Gavins Point Dam. The 2009 May spring pulse created no socioeconomic impacts at any of the monitored sites. A flow attenuation rate was estimated for the May 2009 spring pulse using observed flow records at eight main stem gages along the Missouri River. The 6.1-kcfs spring pulse was estimated to attenuate at a rate of 1.1 kcfs for every 100 river miles in May 2009. The observed May 2009 spring pulse was 1.5 kcfs at Kansas City, MO and is estimated to have attenuated by 77. Similar results were determined for the 4.5-kcfs March 2008 spring pulse in the 2008 monitoring report. The March 2008 spring pulse attenuated at a rate of 1.1 kcfs for every 100 river miles and was not distinguishable by Kansas City, MO. A stage attenuation rate was also estimated for the May 2009 spring pulse. In general, the 1.8-ft May 2009 spring pulse attenuated at an approximate rate of 0.4 ft for every 100 river miles. This analysis was also completed for the March 2008 and May 2006 spring pulses.
- Hydrology, Limnology and Potamology