🎯 Learning Objectives
- Create Buffers to represent zones of influence or danger.
- Perform Overlay Operations (Intersect, Clip) to combine multiple datasets.
- Calculate Geometry Attributes (Area/Length) of the new features.
- Solve a multi-step spatial problem: "How many schools are in the danger zone?"
📂 Scenario: The Chemical Spill
A tanker truck has overturned on Highway 290, spilling hazardous chemicals. The Emergency Response Team estimates a danger zone of 1 mile radius around the crash site. You must identify all schools and hospitals within this zone.
lab05_vector_analysis.zip
Contains: Crash_Site.shp, Schools.shp, City_Parcels.shp
🛠️ Step-by-Step Instructions
Select your preferred GIS platform to view instructions:
Buffer Zone
1. Open the Geoprocessing Pane.
2. Search for Buffer (Analysis Tools).
3. Input: Crash_Site.
4. Distance: 1 Mile. Dissolve: No Dissolve needed.
5. Run. You now have a circle layer.
Select by Location
1. Go to Map tab > Select by Location.
2. Input Features: Schools.
3. Relationship: Intersect.
4. Selecting Features: Crash_Buffer.
5. Click OK. The schools inside the circle turn blue.
Clip Parcels
1. Search for Clip tool.
2. Input Features: City_Parcels.
3. Clip Features: Crash_Buffer.
4. Output: Impacted_Parcels.
5. Run. This creates a new dataset of ONLY the land inside the zone.
✅ Submission & Assessment
To complete this lab, you must submit:
- List: The names of the schools falling within the danger zone.
- Number: The total area (in acres) of the
Impacted_Parcels. - Map: A layout showing the Buffer, the Impacted Parcels, and the identified schools.