WQX 3.0 Migration

This vignette walks through how to download WQX 3.0 data from the WQP and rename the columns back to their WQX 2.0 equivalents. Check out the WQX3.0 Data Now Available on the Water Quality Portal blog for more information about the new WQX 3.0 profiles and WQP beta web services! In addition, USGS provides a summary of the current status of WQP functions in dataRetrieval here.

First, install and load the remotes package specifying the repo. This is needed before installing EPATADA because it is only available on GitHub (not CRAN).

install.packages("remotes", repos = "http://cran.us.r-project.org")
library(remotes)

Next, install and load EPATADA using the remotes package. USGS’s dataRetrieval and other TADA R Package dependencies will also be downloaded automatically from CRAN with the TADA install. If desired, the development version of dataRetrieval can be downloaded directly from GitHub (un-comment).

remotes::install_github("USEPA/EPATADA",
  ref = "develop",
  dependencies = TRUE
)
# remotes::install_github("USGS-R/dataRetrieval", dependencies=TRUE)

Finally, use the library() function to load the TADA R Package into your R session.

library(EPATADA)

Let’s use USGS’s dataRetrieval R package to query the WQP beta web services and retrieve the new WQX 3.0 full physical chemical profile.

wqx3_fullPhysChem <- dataRetrieval::readWQPdata(
  statecode = "Illinois",
  countycode = "DeWitt",
  characteristicName = "Nitrogen",
  service = "ResultWQX3",
  dataProfile = "fullPhysChem",
  ignore_attributes = TRUE
)

We use the readWQPdata and whatWQPsites functions from the USGS dataRetrieval R package within TADA_DataRetrieval. Currently, TADA_DataRetrieval supports only WQX 2.2 (most recent legacy profiles). We are evaluating the new WQX 3.0 beta services and planning to transition the EPATADA R package to utilize these services soon.

To facilitate this transition, we have developed a function that converts all column headers in a WQX 3.0 profile back to their WQX 2.2 equivalents. This enables us to effectively test for backward compatibility. This new EPATADA function, TADA_RenametoLegacy, leverages a crosswalk file that is available on the Water Quality Portal Quick Reference Guide.

wqx3schema <- readr::read_csv("https://www.epa.gov/system/files/other-files/2025-07/schema_outbound_wqx3.0.csv", show_col_types = FALSE)

After retrieving the WQX 3.0 full physical chemical profile, we can use TADA_RenametoLegacy to change the column names back to WQX 2.2 where applicable.

wqx3_legacynames <- EPATADA::TADA_RenametoLegacy(wqx3_fullPhysChem)

Now, we can test other EPATADA package functions as usual, for example, we can run TADA_AutoClean:

wqx3_legacynames <- TADA_AutoClean(wqx3_legacynames)

The WQP and WQX teams (USGS and EPA) are interested in hearing feedback from users on the new WQX 3.0 schema (data profiles) and WQP beta web services (Contact WQX Helpdesk WQX@epa.gov). In addition, please reach out if you run into any issues or questions related to the WQX 2.2 to 3.0 crosswalk file (available on the Water Quality Portal Quick Reference Guide) we developed to assist you with your transition to the new services or data profiles. This EPATADA R package function, , TADA_RenametoLegacy, is provided for WQX 3.0 schema and WQP beta service testing purposes only. We plan to transition the EPATADA R Package to use the WQX 3.0 schema and new WQP services soon. Stay tuned.

TADA Team

2025-09-30