Urban Infrastructure and Erosion School/program name Date

Background Information (for facilitator) Erosion is the process by which rock and soil are removed from a particular location by agents such as flowing water, wind, glaciers, and gravity. It is distinct from other geologic processes such as mechanical or chemical weathering, transportation, and deposition. Weathering is the breakdown of rock, not the removal of rock. Transportation is the movement of eroded rock material by various means, such as wind or water, from one place to another. Deposition occurs when the transported materials are finally laid to rest, usually at a lower elevation, where they can become part of the soil or eventually once again become rock. Weathering, erosion, transportation, and deposition all act together as a part of the rock cycle. These processes help to create, shape, and ultimately destroy many of the landforms on Earth, including canyons, deltas, beaches, caves, glacial craters, plains, and sea cliffs. It is important to distinguish between the processes of erosion, weathering, transportation, and deposition. Erosion is the removal of rock or soil from where it originally formed, or from where it was later deposited, and weathering is the physical or chemical breakdown of rock. In the case of mechanical weathering, rock breaks down due to forces such as abrasion, ice wedging, or thermal expansion. Chemical weathering occurs when rocks break down by reacting chemically with substances such as water or chemicals from organisms such as lichen. Erosion is distinct from transportation in that, while erosion is the removal of material, transportation is the movement of eroded material to another location. Natural agents such as water or wind transport the eroded material to other places. After rock or soil has been transported, it is deposited in a new location that is at a lower elevation; this deposition is caused by the force of gravity. The mode of erosion and transportation depends on the slope of the land and the materials of which the land consists. Steeper slopes and more loosely cemented rock materials can produce rock falls and landslides, whereas gentler slopes made of more consolidated materials are more likely to change gradually as materials move down slope in a process known as creep. Landforms that are produced by the combination of erosion, gravity, and transportation by water include landslides, mudslides, glacial lakes, sandy beaches, deltas, and canyons. Note that the terms landslide and mudslide can be used to refer to the transportation event as well as the resulting landform.

Agenda Opening (30 minutes) Setting the Stage (15 minutes) Activity: Go with the Flow (45 minutes) Break (15 minutes) Setting the Stage (5 minutes) Activity: The Trail That Would Fall (60 minutes) Cyber Investigations (15 minutes) Virtual Lab: Erosion – Here Today, Gone Tomorrow Lunch (30 minutes) Recess: Water Balloon Race (30 minutes) STEM-tastic Careers (30 minutes) Dream School Engineering Challenge: Phase Five (45 minutes) Mind Snacks (20 minutes) Dream School Engineering Challenge: Phase Six (40 minutes) STEM Camp Notebook Reflection (10 minutes) Wrap Up (5 minutes) Dive Into Digital Project (60 minutes)

Learning Objectives To explain erosion To comprehend how erosion can damage urban areas To discover how urban infrastructure can affect erosion

Today’s Vocabulary Erosion Weathering Physical Chemical Sediment

Setting the Stage

What is Erosion?

Activity: Go With The Flow

Setting the Stage

How does urban development affect erosion? Video: Urban Development: A Process of Depleting and Replenishing the Land

Activity: The Trail That Would Fail

Cyber Investigations

Virtual Lab

STEMtastic Careers

How do the scientists at The Nature Conservancy help protect urban infrastructure from the forces of erosion? In addition to protecting urban infrastructure from erosion, what other benefits come from the work of these scientists? What inspired these scientists to do the kind of work that they do?

Dream School Engineering Challenge: Phase Five

Mind Snack

Dream School Engineering Challenge: Phase Six

Notebook Reflection Describe the measure(s) your team is taking to mitigate erosion around your Dream School’s property.

Wrap Up

Think about this… So far, we have discussed earthquakes and erosion. What other geologic factors do you think must be accounted for when designing urban infrastructure and your Dream School?