What you will make

A buffer layer and spatial-join output with a short methods note naming the question, distance, units, target, join feature, and match relationship.

A buffer creates a defined distance area, while a spatial join transfers attributes based on a spatial relationship. Used together, they can answer questions such as which supplied sites fall within a chosen distance of a service. The distance and relationship must come from the question, not from a default tool setting.

• Formulate a spatial question before selecting a tool.
• Create a buffer with explicit units and interpret a spatial join's target and join features.
• Check count fields and limitations before communicating a result.

Watch and try it

Work through the method

1. Write the question

   State what should be counted or compared, the study area, and the distance basis. For example: which candidate sites are within a stated walking-distance screening radius of a supplied service point? Do not call a straight-line buffer a walking network distance.

   Check your work: The question names the feature, relationship, distance, and units.

2. Check measurement context

   Inspect the source coordinate systems and choose a suitable projected workflow or geodesic method for the geography. Confirm that the buffer distance has explicit units and is not being interpreted from unknown coordinate units.

   Check your work: Your methods note identifies the coordinate system and distance units.

3. Run Buffer

   Search geoprocessing for Buffer, select the service or other question-relevant features, set the intended distance and units, and choose whether overlapping areas should remain separate or dissolve. Save the result in the project geodatabase.

   Check your work: The result has the intended coverage and does not merge areas unless the question calls for it.

4. Choose join direction

   Set candidate sites as Target Features if each output row should represent a site. Set the buffer polygons or service features as Join Features according to the relationship being tested. Choose Intersect, Within, or another documented match option deliberately.

   Check your work: You can explain what one row of the output represents.

5. Run and inspect Spatial Join

   Use Join one to one when you want one output record per target with aggregation where needed. Review Join_Count, target identifiers, field mapping, and records with no matches. Use one-to-many only when separate matching records are useful.

   Check your work: Output row count and Join_Count make sense for the selected relationship.

6. Communicate the boundary

   Map the output with a title that says it is a proximity screen. Report the distance and units, data date, and missing coverage. Explain that proximity does not establish service capacity, access, eligibility, or causation.

   Check your work: Your map caption avoids presenting a screening count as a final decision.

Screen sites near a supplied service

1. Write a one-sentence question using the supplied candidate-site and service layers.
2. Buffer the service features using a documented distance and explicit units.
3. Spatially join the buffer to candidate sites with candidates as targets if each output row should represent one site.
4. Review unmatched sites and Join_Count, then export a map and CSV table.

Bring the method into a product

• Proximity-screen map
• CSV output and brief methods note

Suggested formats: PDF, PNG, CSV.

Reflect: What would need to change if the question asks about travel time by road rather than straight-line proximity?

Avoid these mistakes

• A straight-line buffer is not a route, travel time, or service-area network analysis.
• Reversing target and join layers changes what one output row represents.
• A count of nearby features does not prove capacity, access, eligibility, or causal impact.