Lab-Streams&Flooding-Spring2024

Streams and Flooding GEL 111 – Geology Wake Technical Community College Instructor: Ian C. Brown Part 1 Complete the StreamLab 2022 SoftChalk exercise in the folder labelled “Chapter 16 – Streams & Flooding”. In this exercise, you will visit a few streams to identify landscape features and calculate discharge. This SoftChalk Lesson is graded and contributes 50% of the total points for this lab. You will have two attempts when completing it. Part 2 A hydrograph is a graphical representation of the change in a stream’s discharge with time. Many hydrographs will record both the streams discharge as well as the stream’s stage (height in feet). Most stream hydrographs will also indicate the flood stage , the amount of discharge or elevation required for the stream to overflow its banks creating a flood. During a flood event, the hydrograph for a stream will show that the discharge has risen above flood stage, or the stream’s stage shows an elevation well above flood stage. The duration of the flood is identified by the length of time that the discharge or stage exists above flood stage. This can be measured easily by observing the time scale along the horizontal axis of the hydrograph. The time scale will show when the flood began and when it ended. The image below shows the hydrograph for the Neuse River at Goldsboro, NC, during Hurricane Mathew, October 2016. With a flood stage of 18 ft, the flood began just before 10:00 pm on October 8. The water appeared to still be rising when this hydrograph was recorded on October 10 and was projected to last for several days. Figure 1. Hydrograph from the Neuse River recorded during Hurricane Matthew, 2016 Streams & Flooding 1 Date: Name:

Table 1 below provides discharge data for two streams recorded over an 11-day period. Stream 1 Stream 2 Day/Time Stage (ft) Day/Time Stage (ft) Mon 06/18 12:00 am 2 Mon 06/18 12:00 am 4.5 Mon 06/18 12:00 pm 2.5 Mon 06/18 12:00 pm 4.5 Tue 06/19 12:00 am 3 Tue 06/19 12:00 am 4 Tue 06/19 12:00 pm 3 Tue 06/19 12:00 pm 4.5 Wed 06/20 12:00 am 3.5 Wed 06/20 12:00 am 5 Wed 06/20 12:00 pm 4 Wed 06/20 12:00 pm 7 Thu 06/21 12:00 am 4.5 Thu 06/21 12:00 am 10 Thu 06/21 12:00 pm 5 Thu 06/21 12:00 pm 14 Fri 06/22 12:00 am 5.5 Fri 06/22 12:00 am 16 Fri 06/22 12:00 pm 6 Fri 06/22 12:00 pm 14 Sat 06/23 12:00 am 7 Sat 06/23 12:00 am 9 Sat 06/23 12:00 pm 8 Sat 06/23 12:00 pm 8 Sun 06/24 12:00 am 8.5 Sun 06/24 12:00 am 7.5 Sun 06/24 12:00 pm 8.5 Sun 06/24 12:00 pm 7.5 Mon 06/25 12:00 am 9 Mon 06/25 12:00 am 7 Mon 06/25 12:00 pm 8.5 Mon 06/25 12:00 pm 7 Tue 06/26 12:00 am 8 Tue 06/26 12:00 am 7 Tue 06/26 12:00 pm 7 Tue 06/26 12:00 pm 7 Wed 06/27 12:00 am 6 Wed 06/27 12:00 am 6.5 Wed 06/27 12:00 pm 5.5 Wed 06/27 12:00 pm 6.5 Thu 06/28 12:00 am 5 Thu 06/28 12:00 am 6.5 Thu 06/28 12:00 pm 5 Thu 06/28 12:00 pm 6 Table 1. River Stage data for Streams 1 and 2 1. Create simple hydrographs for Streams 1 and 2 using Microsoft Excel. Follow the procedure below; [6] (a) Copy the data for each stream into Microsoft Excel. Be sure to have two separate tables in the Excel document, one for each Stream. (b) Select the entire table with the Stream 1 data (all cells and titles) and then select the ‘Insert’ tab on the menu. (c) On the Insert tab, click on ‘Recommended Charts’ to see a selection of possible charts/graphs. (d) Select the ‘Line Chart’ and click ‘Ok’. Your hydrograph should now be inserted in the Excel workbook. Label the hydrograph appropriately. (e) Repeat steps (b) to (d) with the Stream 2 data to insert the Stream 2 hydrograph. NB. Save the Excel file with the two hydrographs inserted. You will upload this file when completing the Lab Quiz. 2. Stream 1 has a flood stage of 7 feet . Mark the position of this flood stage on the Stream 1 hydrograph. (Select the ‘Insert’ tab. In the ‘Illustrations’ group, click ‘Shapes’. Select ‘Line’ to draw the line on your graph to identify the flood stage [2] 2