Run a constraint map analysis (similar to the Buildable area analysis) on a larger geographic area to determine how buildable an area is prior to searching for parcels.
Overview of Prescan
The Prescan tool allows users to evaluate large geographic regions for key hazards and create constraint maps before even pulling in parcels.
- It can help visualize the constraints of a large area to determine if siting makes sense in a region
- It can be used to help make it easier to avoid pulling in parcels in an area that won't be feasible for development.
The Parcel search tool (in the parcels tab) is not connected to the Prescan constraint map output. Please read below for ways that you can pull in land based on what was marked as buildable in the Prescan analysis.
Create a new project
The Prescan tool is only available on an existing project.
Create a new project first before following the next steps.
Run Prescan
Create scan area
The most common ways to create an area to Prescan are to:
- Trace/draw scan area using drawing tools (come back to this page after tracing the area; don't run the parcel search task)
- Create scan area(s) around target substations and/or lines using the Combo buffer tool
Open the Prescan tool
To access the Prescan tool, complete the following steps:
- Click on the scan area polygon on the map
- In the polygon/buffer pop-up window, click on the See Actions button
- Select Project Tasks
- Select Prescan
This will open up the Prescan form.
Fill in the Prescan form and run the analysis
Fill in desired hazard settings on the Prescan form and run the analysis.
- Turn on desired hazard layers for analysis and input desired setbacks/parameters
These settings are the same as those available on the Buildable area form.
- Click Run to start the analysis
View Prescan constraint maps
The analysis will decompose the scan area into smaller sections to process one-by-one. As each section process, the constraint map will begin filling in.
Purple areas are those that are buildable based on the user-input constraints.
To view the Prescan constraint maps in the future, when returning to a project that previously had Prescan, there will be a legend in the bottom-left corner of the map with an airplane icon.
Click the airplane icon to redisplay the Prescan constraint maps.
Identify parcels
Once the Prescan analysis has completed, use the constraint map to help target where to add parcels through one of the following methods.
The Prescan tool is not connected to the general Parcel Search task available in the Parcels Tab.
- Use the Parcels layer to add parcels in target areas one-by-one
- Trace/draw custom parcel search area to pull in parcels that overlap with the most buildable areas on the map
Finding parcels may be easier if you remove all of the constraints from the constraint map except the Buildable Area. Here's a guide to hiding/showing constraints/hazards.