Pedagogy in Action > Library > Teaching with SSAC > Examples > Flood Days and Good Canoeing Days at Congaree National Park

Flood Days and Good Canoeing Days at Congaree National Park

Mark C. Rains (University of South Florida), David C. Shelley (National Parks Service) and Len Vacher (University of South Florida)
Cover page by Len Vacher, University of South Florida

This activity was selected for the On the Cutting Edge Reviewed Teaching Collection

This activity has received positive reviews in a peer review process involving five review categories. The five categories included in the process are

  • Scientific Accuracy
  • Alignment of Learning Goals, Activities, and Assessments
  • Pedagogic Effectiveness
  • Robustness (usability and dependability of all components)
  • Completeness of the ActivitySheet web page

For more information about the peer review process itself, please see

This page first made public: Jun 27, 2009

This material was originally developed by Spreadsheets Across the Curriculum as part of its collaboration with the SERC Pedagogic Service.


In this Spreadsheets Across the Curriculum activity, students work with U.S. Geological Survey hydrograph data to determine the probability that the water level of Cedar Creek, which flows through Congaree NP, will be within a particular range on a given random day. The data are daily stage heights over the ten-year period October 1 1998 through Sept 30 2008. These data are supplied on a spreadsheet that the students download from the module. The method of solution is to count the number of days (out of the 3653 days of the record) that the water-level of Cedar Creek was above 8 ft (when some trails are flooded) and the number of days when it was in the range of 2-6 ft (when Cedar Creek is neither too shallow nor too swift for canoeing or kayaking by typical visitors to the Park). The students use the COUNTIF function to count the number of days when the water level is within the stipulated range, the COUNT function to count the total number of days, and the ratio of the two to determine the probability. The intent of the module is to introduce Geology of National Parks students to the frequency concept of probability.

This material is based upon work supported by the National Science Foundation under Grant Number NSF DUE-0836566. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the National Science Foundation.

Learning Goals

Slide 3 of the module.

Students will:

  • Read background slides about Congaree National Park; floods and floodplains; and classic and frequency probability.
  • See a 10-year hydrograph of daily stage data for Cedar Creek; download a spreadsheet containing the data behind the plot; view an image of the USGS gage station in the Park that is gathering the data; and connect to the Web site to see the data in real time.
  • Use the COUNTIF function to count the number of days in the 10-year period that the water level was above 8 ft and use the result to calculate the probability that Cedar Creek will be flooded on a random day that they might visit. Similarly, they will count the number of days that the water level was below 2 ft and the number that it was above 6 ft, subtract those two numbers from the total number of days, and then calculate the probability that Cedar Creek will be within the range for good canoeing/kayaking on the random day of their visit.

In the process students will:

  • Learn that Congaree National Park is a river swamp.
  • Learn that floods are a natural and not unusual occurrence on floodplains – the core geoscience literacy concept of the module.
  • Gain some experience with calculating probabilities for craps (classic probability).
  • Distinguish between classic probability and frequency probability, the latter being the core quantitative literacy concept of this module.
  • Learn what a hydrograph is and work with real data from one.
  • Learn that the USGS is continuously monitoring Cedar Creek in Congaree National Park – a Natural Resource Challenge connection.
  • Get a sense of the numerical values for probabilities of normal events – for example (the punchline), the probability that Cedar Creek will overtop its banks on a random day (4.2%) is about the same as the probability of rolling a 3 in craps (5.6%).

Context for Use

Slide 11 of the module.
This module aims to introduce the concept of probability into the Geology of National Parks course at USF. Probability (risk), like order of magnitude (billions and trillions), is a quantitative literacy concept that is crucially relevant to understanding today's world, yet many students can go through their entire college experience without exposure to it. Geology, through the subject of geological hazards, provides good opportunities and context to teach the concept. Thus this module is seen as one of a number of modules in the collection that can be rotated in and out of Geology of National Parks for the purpose of teaching probability. This one uses the context of flow frequency, briefly discusses flood hazards (2 slides), and works directly with the definition of probability as a ratio. The three slides on probability include background on classic probability through consideration of the familiar craps (rolling two dice) and then defines frequency probability to set up the activity of using the COUNTIF function.

This module could be used as one of the first modules in Geology of National Parks. It builds directly on material covered in the introductory module "Spreadsheet Warm Up for Geology of National Parks Modules."

The module stops short of flow-duration curves, which are standard fare for flow frequency analyses in environmental hydrology courses. Flow-duration curves will be picked up in a second module (in preparation) using the same data set. That subject is anticipated in one of the end-of-module questions in this module.

We anticipate that the pair of Cedar Creek flow-frequency modules will be used in various ways in different courses in our Department. The module on the flow-duration curves will be a little more mathematically challenging than this one on the basics of probability. For Geology of National Parks, we expect that on semesters when this module is used, the module on flow-duration curves could be made available for "further study," possibly as extra credit. For Fluid Earth - Hydrology, a majors' course, the module on flow-duration curves could be a main activity on flow frequencies with this one on probability basics being a warm up. For Computational Geology, a quantitative literacy course for our majors, this module could be a quick introduction to a short series of probability modules on problems in a variety of geological contexts.

Natural Resource Challenge. This module can be used to illustrate activities associated with the NPS Natural Resource Challenge. It illustrates the role of government agency partners in the Inventory and Monitoring program (the USGS) and the use of I&M data in management (knowing when trails are flooded and creek passages are problematic). The stream gage explored here is one of 54 historic and operating gages in the Southeast Coastal Network (the I&M Network including Congaree) that provide data for the vital sign, Surface Water Dynamics. The objectives of the work supporting this vital sign are (1) to determine the status and trends of discharge in streams that flow into park boundaries and (2) to determine the frequency, duration, and magnitude of stream discharge during peak flow events. The vital sign, Surface Water Dynamics in the SECN

Description and Teaching Materials

Slide 12 of the module.

The module is a PowerPoint presentation with embedded spreadsheets. Click on the link below to download a copy of the module.

Optimal results are achieved with Microsoft Office 2007 or later; the module will function in earlier versions with slight cosmetic compromises. If the embedded spreadsheets are not visible, save the PowerPoint file to disk and open it from there.

The above PowerPoint presentation file is the student version of the module. It includes a template for students to use to complete the spreadsheet(s) and answer the end-of-module questions, and then turn in for grading.

This module contains two slides of end-of-module questions. The first slide sticks close to the material in the module. The second is more challenging. It can be used to explore some issues in more depth or as a source of individual assignments for students who would like more information.

An instructor version is available by request. The instructor version includes the completed spreadsheet. Send your request to Len Vacher ( by filling out and submitting the Instructor Module Request Form.

Teaching Notes and Tips

The module is constructed to be a stand-alone resource. It can be used as a homework assignment, lab activity, or as the basis of an interactive classroom activity. It was used as an out-of-class activity in a senior-elective course, Environmental Geology of the National Parks (for geology majors and nonmajors), during development of the module in Spring 2010. The module was used after the students had worked through several other modules. In general, the students considered this module to be one of the more challenging of the collection, but well within their range of expectations for level of difficulty. It has not been implemented yet in the introductory-level Geology of National Parks course.


The module contains end-of-module questions that can be adapted for assessment. The instructor version contains a pre/post-module test that can be used for assessment of our core literacy issues. The module has not been implemented, and so we have no assessment data for it.

References and Resources