The Bureau of Reclamation will be conducting an aerial survey of the lower Colorado River and mainstream reservoirs from Hoover Dam to the international border with Mexico, between November 21, 2021 and December 20, 2021, to collect high resolution topo-bathymetry data.
During this time, an airplane operated under contract with the Bureau of Reclamation will be making low-level flights over part of the lower Colorado River and reservoirs. Anyone observing the low-flying plane should not be alarmed if they see it fly overhead or pass below the horizon. The contractor will be following all guidelines established by the Federal Aviation Administration and the aircraft will be operated by experienced pilots specially trained for low-level flying.
Throughout the aerial survey timeframe, hourly reservoir releases and river heights during portions of the day may be more variable than typical for this time of year to optimize survey data collection. Although these releases fall within normal operational parameters, all river users should be aware that lower than normal river flows may expose or create natural hazards such as sandbars, gravel bars, unstable riverbanks, floating or submerged debris, or other unfamiliar obstacles, and should exercise caution.
In particular, on November 23, flows out of Davis Dam will be reduced to approximately 1,800 cubic feet per second from 5:00 am to 1:00 pm MST. Access to the Colorado River below Davis Dam will be very limited and extra caution should be exercised if use of the river is planned during these times.
Planned operations may change depending on operational needs or environmental conditions. Information on releases from Davis and Parker Dams can be found on Reclamation’s River Operations website: https://www.usbr.gov/lc/region/g4000/hourly/DavisParkerSchedules.pdf.
Data collected from this work will inform planning, operations, and analyses across multiple Reclamation and Colorado River programs. For additional information regarding the aerial river and reservoir surveys, please contact Jay Nemeth, Supervisory Civil Engineer, at 928-343-8137 or jnemeth@usbr.gov. If you have any questions regarding reservoir releases, please contact the Lower Colorado Basin River Operations Control Center at 702-293-8373 or BCOOwaterops@usbr.gov.
