Eight years in context
Monthly medians · shaded band is the middle 50% of daily values
OREGON · PUBLIC MONITORING NETWORK
Lower Willamette
Tualatin, Clackamas & Lower Willamette watersheds
USGS observations2018–2025 · Historical snapshotLoading verified records…
Loading the USGS data snapshot…
Turbidity2025Median of daily values
Basemap unavailable. Station locations and watershed boundaries remain visible.
20182019202020212022202320242025
LINKED ANALYSIS
Station record
Seasonal pattern
Turbidity & discharge
Paired daily records at this station · logarithmic axes
CONSISTENT MAP SCALE
Compare two observation years
Both maps use the same measurement, season and color ranges.
Baseline
Comparison
Station-by-station change
Differences describe available daily records. Flow, season, coverage and instrumentation can affect comparisons.
BOARD BRIEFING
A clear account of the monitoring record
Prepared from the current measurement, year, season and data-status filters.
TRACEABLE FROM MAP TO SOURCE
Download all observationsReal observations. Documented methods.
This public demonstration uses USGS records from Oregon. It contains no client monitoring data.
What is being measured?
Turbidity: daily median, USGS parameter 63680, in formazin nephelometric units (FNU). Turbidity measures optical cloudiness; it is not suspended-sediment concentration or sediment load.
Discharge: daily mean, parameter 00060, ft³/s. Temperature: daily mean, parameter 00010, °C. Dissolved oxygen: daily mean, parameter 00300, mg/L.
Each displayed period value is the median of available daily values at one station. It is not a basin-wide average or a count of field samples.
How comparisons are calculated
Calendar years run January–December. Winter includes January, February and December of the selected calendar year. Filters apply to station summaries, comparisons, charts, reports and selected-data exports.
Monthly charts display a median only when at least 15 valid daily records are available. The band spans the 25th–75th percentiles. Gaps are never interpolated.
Coverage is the fraction of calendar days with a numeric observation after filtering. Percentage change is shown only when both periods have at least 75% coverage and the baseline is nonzero. Temperature changes are absolute differences in °C.
What these data can support
Explore spatial differences, seasonal patterns, changes over time and associations between turbidity and discharge. The scatterplot matches records by station and date and excludes nonpositive values from logarithmic axes.
A before/after difference alone does not establish the effect of restoration. That requires project dates, reference sites, comparable sampling and analysis of flow and other influences.
These are public USGS coordinates. A district deployment would use an agreed privacy approach for private properties and landowners.
Sources & quality
Approved records are the default. The data-status filter can include provisional and other statuses; USGS can revise those records. Qualifiers are preserved in downloads.
- USGS Water Data APIs
- USGS The National Map · topographic basemap
- Watershed Boundary Dataset · HUC8
- Source requests and SHA-256 checksums
Watershed outlines provide geographic context. Point values are not extended across watershed areas. This selected network is not a complete regional inventory.
Station data inventory
Numeric daily records in the downloaded 2018–2025 snapshot, before status filtering.
| USGS station | Turbidity | Discharge | Temperature | Dissolved oxygen |
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