Virgil Creek, Dryden Lake and tributaries

Note: The points on this graph reflect the average levels or concentrations of each water quality parameter. To see the individual data points that make up these averages, please scroll down and select a Sampling Location or a Monitoring Event from the tables below.

Selection of water quality indicators is controlled by drop-down menu on the upper right. Graph presents average values for both SYNOPTIC LOCATIONS and REDFLAG LOCATIONS over all monitoring events (see below right, table of events). Synoptic and Red Flag locations are ordered downstream to upstream (left to right) according to their distance from the stream mouth (see below left, table of locations). If distance to mouth has not been determined, the location defaults to the right end of the graph. Graph distances do not correspond to actual miles to mouth. INVESTIGATIVE LOCATIONS and BIOLOGICAL LOCATIONS are excluded.

Separate averages are reported for samples collected under base flow and stormwater conditions. These stream flow categories are loosely defined. BASE FLOW corresponds to normal or low flow conditions. STORMWATER corresponds to elevated flows following rain or snow melt, as judged by online hydrographs of USGS gauging stations, if available, and/or as judged by volunteers based on their familiarity with the stream and their observation of factors such as stream turbulence and turbidity. Though loosely defined, these two flow categories provide a useful approximation of the impact of runoff on water quality. See metadata for a description of methods for estimating stream discharge and nutrient loading.

This table lists all SYNOPTIC LOCATIONS , REDFLAG LOCATIONS , INVESTIGATIVE LOCATIONS , and BIOLOGICAL LOCATIONS in the watershed of the monitoring set, their latitude and longitude coordinates, and the number of river miles to the stream mouth, where applicable. Select a location to view a detailed site map and timeline of chemical and microbiological results.

This table lists the dates of all chemical and microbiological monitoring events since the beginning of the monitoring set. A PARTIAL EVENT indicates that less than 90% of SYNOPTIC LOCATIONS were sampled. Select a date to navigate to a graph and table of raw chemical and microbiological data from the corresponding event.