The Carroll Cave Stream Flow Project is complete for 2019. The file linked at the bottom of this post contains all of the raw data, the processed data and full year graphs in both PDF and JPG format.

The data shows two major floods in the cave. One was in early May and the other in early June. The May flood reached just over 8 feet in Thunder River at the ladder, with almost 18 feet below Thunder Falls. The June flood reached about 3 feet at the ladder and 13 feet below Thunder Falls.

The May event corresponds with about 4 inches of rainfall. The June event came with around 5 inches of rain, though that was spread out over several days.

The lesson is clear, and is not changed from previous years. Carroll Cave can and will flood to dangerous levels. All trips into the cave need to bear in mind what the weather forecast holds for rain. This goes double for trips to downstream Thunder River.

The ZIP file contains a lot of files. Based on the filename extension, this is what they are:

.HOBO – These are the raw data files directly off of the loggers. To deal with these files you need a copy of HoboWare. A free version is available. It works but has some limits on functionality. Go to to get it. The date on the file is the date it was downloaded. The first and last files contain data from 2018 and 2020 which can be ignored. The 2018 data is part of last year’s report, and the 2020 data will be part of the report next year.

.JPG and .PDF – These are the data graphs. There is a separate file for each logger, plus one PDF that has all of the graphs in one document.

.CSV – These files are the processed data as exported from HoboWare in comma-separated format. These files can be loaded into Excel, LibreOffice or any other charting program to make your own views of the data.

.KST – These files are for the graphing and charting program that I used to generate the graphs.