This data release contains files that are associated with the publication "Understanding and predicting iron fouling associated with drainage from roadway sites constructed with rock-fill in New Hampshire, USA". Each zipped file contains a data table or raster file and an associated metadata file. IronFoulingCutFillData.zip contains a .csv file and .xml metadata file related to the roadcut and rock-fill locations used to develop a statistical model to predict the probability of iron fouling at roadway sites constructed with rock-fill in New Hampshire. Water_Quality_Measurements.zip contains a .csv file and .xml metadata file for water quality field measurements made at drainage areas from a subset of the rock-fill locations in the IronFoulingCutFillData files. The NHIronFoulingProb.zip file contains a geotiff raster of the predicted probability of iron fouling occurring at any location within New Hampshire where rock-fill from that location is used and contacts drainage. This is the output from the statistical model prediction. NHIronFoulingProb.zip also contains an .xml metadata file.