Publication

RiverEyes Observations for 2011

URL: https://webapps.usgs.gov/mrgescp/documents/Hatch_2011_RiverEyes-Observations-for-2011.pdf

Date: 2011/11/01

Author(s): Hatch M.D.

Publication: Prepared for U.S. Bureau of Reclamation. Prepared by SWCA Environmental Consultants, 126 p.

Abstract:

Reconnaissance of portions of the Middle Rio Grande is mandated by Reasonable and Prudent Alternative Element C of the 2003 Biological Opinion (U.S. Fish and Wildlife Service 2003), known as "RiverEyes." RiverEyes monitoring must be performed when flows are less than 300 cubic feet per second (cfs) at San Acacia Diversion Dam. RiverEyes provides current information on river flows that allow action agencies to react quickly to rapidly changing conditions on the river, facilitate coordination among the agencies to prevent unexpected drying, and prepare for Rio Grande silvery minnow (Hybognathus amarus) rescues.

Hydrologic conditions in the Middle Rio Grande were monitored generally from April 5 to October 31, 2011, to document spatial and temporal effects of low discharge flow regimes during periods when discharge was less than 300 cfs over San Acacia Diversion Dam. Channel drying was restricted to the Isleta and San Acacia reaches over the period of monitoring. The location and extent of channel drying varied within each reach over the period of monitoring in response to localized and regional storm events, as well as out-of-channel uses of water. The first and last occurrence of channel drying in the Isleta Reach was recorded on July 9 and October 29, 2011, respectively. The first and last occurrence of channel drying in the San Acacia Reach was recorded on April 22 and October 31, 2011, respectively.