DNR data available for Story County

Locations

Iowa DNR’s AQuIA database includes water quality data for many water bodies in Story County. Here we are looking a surface water data that may have been collected as part of the ambient monitoring networks for lake and streams, for regulatory and assessment purposes, lab tests backstopping the IOWATER volunteer program, and for special projects. https://programs.iowadnr.gov/aquia

The interactive map below shows sites in Story County with surface water data available from the Iowa DNR, with redder color indicating sites that were tested more often. For example, the South Skunk River has been tested monthly for 20 years as part of the ambient monitoring network. Other sites may have been tested during only one year for a special study or as followup on a fish kill or other assessment.

library(leaflet)
mypalette <- colorNumeric(palette = "viridis", domain = DNR_summary$dates_sampled, na.color = "transparent")
leaflet(DNR_summary) %>%
  addProviderTiles("Stamen.Terrain") %>%
  addCircleMarkers(lng = ~longitude, lat = ~latitude,
             color = ~colorQuantile("YlOrRd", dates_sampled)(dates_sampled),
             popup = ~paste0(name,
                          "<br/>Date range: ",
                          from, "-", to,
                           "<br/>Number of records: ",
                          total_records, 
                          "<br/>Number of days sampled: ",
                          dates_sampled,
                          "<br/>Total analytes tested: ",
                          total_analytes
                          ))

Analytes

The dataset includes tests for 265 different analytes (things you analyze), including:

• Field measurements, such as dissolved oxygen and flow
• Fecal indicator bacteria, such as E. coli
• Inorganic chemicals (generally, naturally occuring), such as chloride
• Nutrients, such as nitrogen
• Pesticides, such as carbonyl
• Volatile organic compounds such as trihalomethanes
• Metals, such as lead

Some analytes are monitored on a monthly basis, others infrequently. Many of these chemicals tested for were not present above the detection limit. Here is a summary of what was tested for, and what was found.

50 analytes were tested at 5 or more sites.

Timing

Sampling schedules depend on the purpose of the program.

# An overview of timing (month and years) for the whole record
filter(DNR) %>%
  ggplot(aes(x = sampleDate, y = name, color = Month)) +
  geom_point() +
  theme_light() +
  scale_x_date(date_breaks = "4 year", date_minor_breaks =  "1 year", date_labels = "%Y") +
  theme(legend.position = "bottom") +
  labs(y = "Site", x = "Year", 
       title = "Timing of DNR surface water testing", subtitle = "by program code") +
  facet_wrap(~projectCode, scales = "free_y", ncol = 1)

Lakes are only sampled during the warm season.

# An overview of timing (month and years) for the whole record
filter(DNR) %>%
  ggplot(aes(x = sampleDate, y = name, color = Month)) +
  geom_point() +
  theme_light() +
  scale_x_date(date_breaks = "4 year", date_minor_breaks =  "1 year", date_labels = "%Y") +
  theme(legend.position = "bottom") +
  labs(y = "Site", x = "Year", 
       title = "Timing of DNR surface water testing", subtitle = "by water type") +
  facet_wrap(~type, scales = "free_y", ncol = 1)

Timing varies within years but it should be possible to filter so that sites are compared during the same months.

filter(DNR, Year == 2009) %>%
  ggplot(aes(x = Week, y = name, shape = Day)) +
  geom_point() +
  theme_light() +
  scale_x_continuous(minor_breaks = seq(0,52, 1)) +
  labs(y = "Site", x = "Week of Year", 
       title = "Timing of sampling, 2009")