This is a first pass at summarizing E. coli data from lakes and rivers across a three-state area, in order to provide some context for recreational impairments in the upper Midwest.
Database: EPA Water Quality Portal
States: Iowa, Minnesota, and Wisconsin
Organizations: This dataset includes state, federal and tribal agencies within this area
Time period: March 15 to November 15, 2022. This analysis focuses on the recreational season. It focuses on the most recent year for which data has been consistently posted.
Data quality: At least 7 samples collected during that recreational season. Additional work needs to be done to clean up inconsistent handling of samples above or below detection limits.
338 stream sites were included in the analysis. 152 lake sites were included.
The color coding on the map is based on Iowa’s waters quality standards.
Green = Meets primary contact recreation standard (<126 colonies/100mL)
Yellow = Exceeds primary contact standard but meets secondary contact recreation standard (126-630)
Red = Exceeds secondary contact recreation standard (> 630)
library(leaflet)
color_ecoli <- colorBin(c('green','yellow', 'red'), bins = c(0,126,630, 10000))
popper <- ~paste0(MonitoringLocationName, "<br/>",
MonitoringLocationIdentifier,
"<br/>E. coli geomean (colonies/100ML): ",
geomean,
"<br/>Number of samples: ",
n)leaflet() %>%
addTiles() %>%
addCircleMarkers(data = geomean_lakes,
lng = ~lon, lat = ~lat,
color = ~color_ecoli(geomean),
radius = 6,
stroke = FALSE, fillOpacity = 100,
popup = popper)leaflet() %>%
addTiles() %>%
addCircleMarkers(data = geomean_rivers,
lng = ~lon, lat = ~lat,
color = ~color_ecoli(geomean),
radius = 6,
stroke = FALSE, fillOpacity = 100,
popup = popper)