15 Streamflow
Flow is derived from active USGS gauges with records that are of at least 30 years’ duration (waterdata.usgs.gov/nwis/sw). Daily means from 213 gauges were used to calculate annual 1-day maximum and 7-day minimum flows for ecoregion and Chinook salmon ESU boundaries. These indicators correspond to flow parameters to which salmon populations are most sensitive. We use standardized anomalies of streamflow time series from individual gauges.
Freshwater habitat indicators are reported based on a hierarchical spatial framework. The framework facilitates comparisons of data at the right spatial scale for particular users, whether this be the entire California Current, ecoregions within the CCE, or smaller spatial units. The framework we use divides the region encompassed by the CCE into ecoregions (Fig. 1.1), and ecoregions into smaller physiographic units. Freshwater ecoregions are based on the biogeographic delineations in (Abell et al. 2008), see also www.feow.org, who define six ecoregions for watersheds entering the California Current, three of which comprise the two largest watersheds directly entering the California Current (the Columbia and the Sacramento-San Joaquin Rivers). Within ecoregions, we summarized data at scales of evolutionary significant units (ESUs) and 8-field hydrologic unit classifications (HUC-8). Status and trends for all freshwater indicators are estimated using space-time models that account for spatial and temporal autocorrelation (Lindgren and Rue 2015).
Streamflow 1 day max Ecoregion indicators:
- Ecoregions:
- Salish Sea & WA coast
- Columbia Glaciated
- Columbia Unglaciated
- Oregon and Northern California Coastal
- Sacramento - San Joaquin
- Southern CA bight
- Component Category: Habitat
- Time Range: 1981 - 2024
- CCIEA Data Contact: correigh.greene@noaa.gov
- Institution: NOAA NWFSC
- Source Data: Streamflow is measured using active USGS gages (http://waterdata.usgs.gov/nwis/sw) with records that meet or exceed 30 years in duration.
- Additional Calculations: Average daily values from 213 gages were used to calculate annual 1-day maximum flows. These indicators correspond to flow parameters to which salmon populations are most sensitive. Standardized anomalies of time series from individual gages were then averaged to obtain weighted averages for ecoregions (for which HUC-8 area served as a weighting factor) and for the entire California current (weighted by ecoregion area).
Streamflow 7 day min Ecoregion indicators:
- Ecoregions:
- Salish Sea & WA coast
- Columbia Glaciated
- Columbia Unglaciated
- Oregon and Northern California Coastal
- Sacramento - San Joaquin
- Southern CA bight
- Component Category: Habitat
- Time Range: 1981 - 2024
- CCIEA Data Contact: correigh.greene@noaa.gov
- Institution: NOAA NWFSC
- Source Data: Streamflow is measured using active USGS gages (http://waterdata.usgs.gov/nwis/sw) with records that meet or exceed 30 years in duration.
- Additional Calculations: Average daily values from 213 gages were used to calculate annual 7-day minimum flows. These indicators correspond to flow parameters to which salmon populations are most sensitive. Standardized anomalies of time series from individual gages were then averaged to obtain weighted averages for ecoregions (for which HUC-8 area served as a weighting factor) and for the entire California current (weighted by ecoregion area).
Streamflow 1 day max ESU indicators:
- ESUs:
- Upper Columbia Spring
- Oregon Coast
- S. Oregon N. California coast
- Upper Klamath Trinity River
- California Coast
- Sacramento Winter
- Central Valley Spring
- Central Valley Fall late Fall
- Puget Sound
- Washington coast
- Upper Columbia Summer Fall
- Snake River Fall
- Lower Columbia River
- Mid-Columbia Spring
- Snake River Spring Summer
- Upper Willamette River
- Component Category: Habitat
- Time Range: 1981 - 2024
- CCIEA Data Contact: correigh.greene@noaa.gov
- Institution: NOAA NWFSC
- Source Data: Streamflow is measured using active USGS gages (http://waterdata.usgs.gov/nwis/sw) with records that meet or exceed 30 years in duration.
- Additional Calculations: Average daily values from 213 gages were used to calculate annual 1-day maximum flows. These indicators correspond to flow parameters to which salmon populations are most sensitive. Standardized anomalies of time series from individual gages were then averaged to obtain weighted averages for each of 17 Chinook salmon ESU boundaries (for which HUC-8 area served as a weighting factor).
Streamflow 7 day min ESU indicators:
- ESUs:
- Upper Columbia Spring
- Oregon Coast
- S. Oregon N. California coast
- Upper Klamath Trinity River
- California Coast
- Sacramento Winter
- Central Valley Spring
- Central Valley Fall late Fall
- Puget Sound
- Washington coast
- Upper Columbia Summer Fall
- Snake River Fall
- Lower Columbia River
- Mid-Columbia Spring
- Snake River Spring Summer
- Upper Willamette River
- Component Category: Habitat
- Time Range: 1981 - 2024
- CCIEA Data Contact: correigh.greene@noaa.gov
- Institution: NOAA NWFSC
- Source Data: Streamflow is measured using active USGS gages (http://waterdata.usgs.gov/nwis/sw) with records that meet or exceed 30 years in duration.
- Additional Calculations: Average daily values from 213 gages were used to calculate annual 7-day minimum flows. These indicators correspond to flow parameters to which salmon populations are most sensitive. Standardized anomalies of time series from individual gages were then averaged to obtain weighted averages for each of 17 Chinook salmon ESU boundaries (for which HUC-8 area served as a weighting factor).
Indicator Download
ERDDAP™ link:
https://oceanview.pfeg.noaa.gov/erddap/tabledap/cciea_HB_FLOW.html
References