Lot grading using Cogo Points Let's You Establish a Dynamic Relationship between Parcels and Roads
In this series we will demonstrate how you can link your parcels to your road using Cogo Points to establish a dynamic relationship between the two. You then use the survey line feature to establish a relationship between the front and back lot locations.
To achieve this, you must do some drawing preparation in advance including an offset interior polyline for each lot and then perform additional sampling at the corner of each of these polylines.
Creating Lot Offset Polylines
The first thing you must do is create offset polylines for each parcel. This can be a time consuming task - but a combination of CAD tools and Civil Site Design tools makes this task relatively painless.
In preparation, make sure that your lot or parcel lines are created on a unique layer (_CSD-Lot-Lines). Next, create a new layer for the lot boundaries (_CSD-Lot-Boundaries) and a layer for the offset polylines (_CSD-Lot-Offsets) which will become the grading strings we will use for lot grading.
To create the boundary polylines:
- Make the _CSD-Lot_Boundaries the current layer
- Use the BO command and select the option to ignore nested islands
- Pick points inside each lot
To create the offset polylines:
- From the Sanitary Tab Select House Offset from the Layout Sewer section
- Complete the form with a 2' - 4' offset and select the _CSD-Lot-Offsets layer.
Watch the video below to see this process in action.
Creating Sampling Lines at Each Lot Line
The next step in the setup process is to add additional sample lines at each corner of the offset polylines fronting the road. These locations will be used to tie the grading string to the road.
To do this, you must resample each road using the Resample Road button on the Roads Tab.