Data Details Page

This 3-part ‘flow’ data package supersedes prior ‘streamgage’ data packages, which only contained streamgage data. Prior streamgage data packages are archived at the TRRP office. This Data Package provides an organized set of time-series reference data relevant to flows in the Trinity River of northern California with geospatial data representing sample locations. The data are organized into 3 subsets:

• Streamgages. An organized compendium of streamgage data throughout the Trinity River watershed (plus the Klamath River above and below the confluence with the Trinity). Data include full historic records, instantaneous stage and flow records where available or where have been specifically obtained by TRRP, and streamgage sites that no longer operate. Streamgage data in this data package are primarily from the USGS and are obtainable online from their National Water Information System (NWIS) or their Instantaneous Data Archive (IDA). Data also include some tributary data collected by agencies or contractors that are not currently available from USGS.
• Reservoir Operations. A single table with reservoir data on storage and release beginning November 1962 (the Trinity River Division dams began retaining water in late January, 1961[1]).
• Restoration Flow Release Schedule. A single table with the scheduled daily release from Lewiston Dam recommended for restoration purposes in the Trinity River. Prior to WY2007, restoration flows were typically subject to limitations and should not be characterized simply as ‘TMC recommended restoration flow schedules’. WY2001 – WY2004 scheduling was limited by court order WY2005 – WY2006 maximum flow rate for scheduling was limited by infrastructure.

More details on restoration flow releases are available in annual reporting of flow releases (e.g. TRRP 2014). Water years are defined as October 1st through September 30th. Version/Edition names will use the water year for which data was recently added.

[1] Date approximated by comparing the ratio of flows between the Lewiston gage and the Coffee Creek gage. Some unusual ratios are visible as early as November, 1960, but only for a few days duration. Although water was being retained, the dams were not considered fully operational for a couple more years.