Module 2 – Flood Probability, Stage Data Collection, Evaluating Risk, and Effects of Climate Change

In this module, students will learn about essential flood concepts including probability, recurrence interval, and risk. They will collect stage data to compare with historical events and predicted probabilities. Students will also visualize cross-sections and aerial maps of flood depths and extents. They will compare their data and visualizations to flood insurance risk maps (FIRMS) and evaluate flood risk in their watershed and community. Then students will analyze flood simulation data based on end-century predictions for influences of climate change on precipitation distributions to understand how a changing climate can affect risk and probability of flood events.

Module 2.1 Understanding Flood Probability: Students will use a flood simulation tool to analyze annual flood events, recurrence intervals, and probability. Students will also calculate 30-year probability and evaluate flood risk on the timescale of a typical mortgage.

Module 2.2 Mapping and Visualizing Flood Risk: Students will take a field trip to points within their watershed where they can measure river stage, draw cross-sections of stage at current levels, 100-year event levels, and flood-of-record levels, to understand what inundation depth looks like at these locations. Students will also draw flood levels onto maps using topography and contours to show the extent of inundation at current, 100-year, and flood-of-record intervals. Students will take their maps and cross sections back to class and compare them with published flood risk insurance maps to evaluate risk for flooding in their communities.

Module 2.3 Effects of Climate Change on Flood Risk: Students will return to the simulations from module 2.1 to collect and analyze simulated annual flood events based on end-of-century predictions for how precipitation distributions will change in the Great Lakes region. Students will again analyze annual and 30-year probability for flooding and evaluate how flood risk may change in the future.