Chart data over time

Use the four time-axis chart tools under Data Analysis to plot a series over time: groundwater levels, lab analyte results, field readings, and continuous logger streams. All four draw date-sorted line charts and let you click a grid row through to the backing record.

Before you start

• Role required: permission to view analysis data for the sites (and, for Time Series, the projects) you want to chart.
• Prerequisites: the underlying data already exists — gauged Water Levels, Lab Results, Field Parameter readings, or Logger readings. Each chart plots what is already in Data Management.

Choose what to chart

These charts fan out one line per series, so a fresh scope leaves the data axes — Locations, plus Parameters or Analytes where the tool has them — unselected. You pick what to plot rather than the tool drawing every series at once. To include everything for the scope quickly, use the Select all in scope button (on Field Parameters and Logger Data, which have two axes) or the Select all checkbox inside a dropdown. Plot stays disabled — with the reason shown beside it — until the required selections are made. The Sites list shows only sites that actually have this tool's data, so you never pick a site that can't produce a chart.

How the tools are grouped

The chart tools sit in two families in the Data Analysis sub-navigation:

• Hydrographs, Field Parameters, and Logger Data are the Monitoring tools. They are site-scoped and share your selected site and date range (see Shared site scope and dates below).
• Time Series is grouped under Analytical, because it charts lab analyte results. It is project-scoped and uses the analytical filters shared with Crosstab, Data Explorer, and the Map (when a map is configured), not the shared monitoring scope.

Every chart draws its line connectors in date order — series are sorted on date, so a wide or out-of-order date range still produces clean, non-zig-zag lines.

Shared site scope and dates

Each Monitoring tool lists only the sites that actually have its kind of data — Hydrographs lists sites with water-level data, Field Parameters lists sites with field-parameter readings, Logger Data lists sites with logger data — so you never pick a site that can't produce a chart. A footnote under the Sites dropdown notes this.

Your selected Sites and the Date Range are shared across the three tools: pick a site and a window in Hydrographs, switch to Field Parameters or Logger Data, and the date window carries over, along with the site if it also has that tool's data (a water-level-only site simply isn't offered on Logger Data). Each tool keeps its own locations, parameters where applicable, and display options. (Hydrographs charts wells rather than a parameter list.)

Time Series is not part of this shared monitoring scope. It carries its own projects, sites, analytes, and screening filters.

Chart groundwater levels (Hydrographs)

Hydrographs charts Water Level gauging events over time, building a Hydrograph for each Well.

1. Go to Data Analysis → Hydrographs.

2. Select Open Filters.

3. In the Hydrograph Filters panel, set:

   Field	What to enter
   Sites	One or more Sites to chart.
   Locations (under Wells)	The wells to plot.
   Start Date / End Date	The date window.
   Target Unit	Feet or Meters — Erde converts the readings to this unit.
   Depth to Water	Optional — add a depth-to-water series on a secondary axis.
   LNAPL	Optional — add a light non-aqueous-phase-liquid band where present.

4. Select Plot. An Overview — Groundwater Elevation chart shows one line per location, followed by a per-location detail chart for each well.

Only valid readings appear on the chart; readings flagged invalid stay visible in Data Management. Each detail chart draws MP Elevation and Well Bottom reference lines where those elevations are recorded for the well. Readings with no measuring-point elevation cannot have a groundwater elevation plotted; their count is noted in a banner above the chart.

Chart lab results over time (Time Series)

Time Series plots Lab Result values for an Analyte over time. It is a trend tool, so it plots every result without deduplicating re-runs or multi-method results.

1. Go to Data Analysis → Time Series.
2. Select Open Filters.
3. In the Analysis Filters panel, set your scope — use Scope by to pick Sites (default) or Projects, choose one or more, and optionally narrow with the other axis under Refine — then choose Locations and at least one entry under Analytes, and set the Start Date / End Date. Optionally choose one or more entries under Screening to draw screening lines.
4. Select Plot. Each chart pane covers one analyte-and-unit combination, with one line per location. Results reported on different bases are plotted as separate series: a dry-weight or lipid-weight result gets its own line, labeled (Dry Weight) or (Lipid Weight), so it is never blended into the same trend line as the as-received result for that analyte.

Non-detect results plot at their detection limit, and the displayed result keeps its non-detect notation (for example < 0.05 or ND), which conveys non-detect status independently of any qualifier. Where a result is shown with a qualifier, it is the validated qualifier only — an unvalidated result shows none. A detected result that reports only an EMPC plots at its EMPC value instead of being dropped from the series. Time Series drops per-result significant figures because it is a trend view; the full result detail is available from the Result Detail panel.

Trend field readings (Field Parameters)

Field Parameters trends Field Parameter readings — pH, dissolved oxygen, conductivity, and the like — recorded during field sessions.

1. Go to Data Analysis → Field Parameters.
2. Select Open Filters.
3. In the Field Parameter Filters panel, choose Sites, Locations, and Parameters, then set the Start Date / End Date.
4. Optionally select Show all readings (default: final reading only). When this is off, each session contributes only its final reading per parameter; when on, every reading is charted.
5. Select Plot. Each chart pane covers one parameter-and-unit combination, plotted against reading time, with one line per location.

Readings with no value are left off the chart. Invalid readings are marked in the chart tooltip and flagged in the Invalid column of the grid.

Chart continuous logger streams (Logger Data)

Logger Data charts the high-frequency Logger Reading values from the Logger Channels on your Logger Streams. Because a channel can hold millions of readings, Erde downsamples on the server: it buckets the readings and charts a minimum, maximum, and average per bucket. For how logger streams, channels, and readings are recorded, see Loggers.

1. Go to Data Analysis → Logger Data.

2. Select Open Filters.

3. In the Logger Data Filters panel, choose Sites, Locations, and Parameters, and set the Start Date / End Date.

4. Set the Resolution and reading options:

   Control	Effect
   Resolution	Auto (default — picks a bucket width so each series is about 1,500 points), Raw (no bucketing, up to the point cap), Hourly, or Daily.
   Include invalid readings	Off by default — leave off so an invalid spike does not distort the min/max envelope.

5. Select Plot. Each chart pane covers one parameter-and-unit combination, plotting the per-bucket average over time, with one line per location.

A Show min/max band checkbox (on by default) overlays the per-bucket minimum-to-maximum envelope so peaks a plain average would hide stay visible. Download raw CSV exports the full, undecimated readings (capped at one million rows; over-cap files are truncated and named accordingly).

Result

Each tool shows its chart (or charts) plus a data grid of the underlying records. A filter summary bar across the top reports the active filters; reopen the panel from the Filters link to refine and re-plot.

In Hydrographs, Field Parameters, and Logger Data, select a grid row to open that record's Data Management detail page; hold Ctrl while selecting to open it in a new browser tab and leave your analysis in place. In Time Series, selecting a grid row instead opens the Result Detail panel in place. Selecting a point on the chart highlights the matching grid row; in Time Series it also opens the Result Detail panel for that point, and in Logger Data it opens a drill-down of the raw readings behind the clicked bucket.

Zoom and export a chart

Drag across any chart to zoom into a rectangular area; hold Shift and drag to pan, or use the mouse wheel to zoom in and out. The actions menu (⋮) in the top-right corner of each chart — also opened by right-clicking anywhere on the chart — offers:

• Export PNG and Export PDF — save the chart as an image.
• Reset zoom — restore the full date and value range.

On Logger Data, this image export is separate from Download raw CSV, which exports the underlying readings rather than the chart picture.

Troubleshooting

Symptom	Cause	Resolution
"No … found for the selected criteria."	No matching records in the chosen sites, locations, parameters, or date range.	Widen the date range or adjust the scope, then re-plot.
Results are truncated to a capped number of points.	The query exceeded the chart's point cap.	Narrow the date range, locations, or parameters. On Logger Data, raise the bucket size by choosing Hourly or Daily.
A banner notes readings with no measuring-point elevation (Hydrographs).	Those readings have no measuring-point elevation, so a groundwater elevation cannot be plotted.	Add the measuring-point elevation on the affected Water Level records.
A site you set in one Monitoring tool appears in another.	Hydrographs, Field Parameters, and Logger Data share one site and date-range selection by design.	Adjust the Sites filter in the tool you are using; it is shared across the three.

Related

• Water levels
• Field parameters
• Continuous loggers
• Crosstabs
• Data Explorer
• Data Analysis and Screening overview