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Public notice for the upgrade and expansion of the water monitoring network in the Sacramento-San Joaquin Delta

September 17, 2021

The U.S. Geological Survey (USGS) provided the public an opportunity  to review and comment on an Environmental Assessment (EA) for the construction, upgrade, and maintenance of new and existing monitoring stations in the Sacramento-San Joaquin Delta (Delta). Public notifications were posted to this website and distributed via social media, but USGS received no comments during the review period.

Steel piling mounted with solar panels, electronics enclosure, and PVC tubing standing in a body of water
Standard configuration of a Sacramento-San Joaquin Delta flow and water quality monitoring station.  The U.S. Geological Survey (USGS) has operated and maintained a monitoring network in the Sacramento-San Joaquin Delta since the 1970’s. The steel pilings house  acoustic doppler velocity meters (ADVM), pressure sensors and/or water quality sondes, solar panels, and navigational safety signage. (Public domain.)

The USGS has operated and maintained a monitoring network in the Delta since the 1970’s to collect flow and water quality data. Over time, as technology improved, and monitoring needs changed, the network has expanded to include more locations and additional parameters. To continue this mission, there is a need for infrastructure maintenance or modification at some of our existing stations and a need for additional infrastructure at new locations. 

As part of a broader effort to implement a more robust monitoring network in the Delta, the USGS California Water Science Center has consulted with several federal, state, and local agencies and has received permits from the California Water Quality Control Board. The California State Historic Preservation Office has concurred with the USGS determination of no historic properties affected for the proposed construction in accordance with the National Historic Preservation Act (36 CFR 800). USGS is in the process of obtaining permits through the U.S. Army Corps of Engineers and a consistency determination with the San Francisco Bay Conservation and Development Commission.    

An EA was completed to address potential noise issues during construction and potential impacts of construction on local threatened or endangered species. As the comment period for EA has ended, USGS has concluded that the proposed project is not a major federal action significantly affecting the quality of the human environment.   

The EA can be accessed here.

The Finding of No Significant Impact can be accessed here

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