You are here

Activity Instructions > Understanding Surface Water and Groundwater Interactions


Time Frame – 150 minutes (2.5 hours). We show an outline for three 50-minute class periods.


Time Breakdown

  • Teacher’s introduction to groundwater, karst, and the Edwards Aquifer: 50 minutes
  • Teacher’s introduction to hydrographs and instructions: 15 minutes
  • Student graphing Hydrograph One: 20 minutes
  • Student assessment of Hydrograph One: 15 minutes
  • Student graphing Hydrograph Two: 15 minutes
  • Student assessment of Hydrograph Two: 20 minutes
  • Class discussion/assessment of Hydrograph Three: 25 minutes

Day 1

Give presentation Introduction to groundwater, karst, and the Edwards Aquifer.


Day 2

Give presentation Hydrographs and introduce the activity. Assign the students in groups of two to a computer and hand them a single copy of the Procedures Packet and give each student a Student Worksheet. The Procedures Packet contains an introduction to the activity which they should read.

The Procedures Packet also contains step-by-step instructions with images on how to create Hydrograph One and Hydrograph Two. After the completion of Hydrograph One students should print a copy of the graph and answer the questions for Hydrograph One on the Student Worksheet.


Day 3

Barton Springs ActivityLinda Ruiz McCall (Program Specialist, Education and Outreach, Water Science and Conservation) from the Texas Water Development Board
holds the compiled hydrograph and leads a discussion with teachers
on the Barton Springs Activity during TXESS Revolution PDA 3B in 2008.

(Photo courtesy H.C. Olson)

Assign each student pair a year for Hydrograph Two (be sure you assign consecutive years) and have them follow the directions in the Procedures Packet for Hydrograph Two. After completing the hydrograph, students should print copies of the graph and answer the questions for Hydrograph Two on the Student Worksheet. If the students have difficulties creating the graphs or have printing problems, provide them with printed copies from the teacher's editions (Teacher's Edition of Hydrograph One and Teacher's Edition of Hydrograph Two) files. (It might be a good idea to have some printed out beforehand.) Hydrograph Three will be a compilation of each group’s printed hydrographs.

For example, if the teacher had 20 students he/she could assign each of the ten groups a year in between 1980 and 1989. Once all the groups have completed the year long hydrograph and printed them, they should piece them all together to make a decade long hydrograph. Combine all of the years and post them in the classroom (i.e., across the board at the front of the room) in order to lead a discussion guided by the questions from Hydrograph Two and any other trends that students have observed.