Designing Ponds in Allsite (Level AI)
Ponds are used in Allsite to provide stormwater detention and storage within your site model. Once drawn, Level AI automatically excavates (“digs out”) the pond to meet your specified volume, depth, invert, and side slope constraints, while balancing the overall site grading.
You create ponds from:
Drainage → Pond
This article explains:
How to draw a pond
All pond settings (as shown in Extended Data)
Global pond defaults (Web Settings)
How Level AI excavates and sizes the pond
Drawing a Pond
Select Drainage → Pond
Draw a closed polygon where the pond will be located.
Open Extended Data to configure the pond settings.
The pond is created on the AS-PONDS layer and stored as a pond feature
How Level AI “Digs Out” a Pond
When Level AI runs:
The pond polygon becomes an excavation zone.
The solver determines:
Bottom level (invert)
Side slopes
Storage depth
The finished surface is reshaped using COGO points inside the polygon to:
Meet either depth or volume targets
Respect maximum cut and fill
Respect defined minimum lip level
Tie smoothly into surrounding grades
Conceptual pond design
Conceptually:
The pond has a bottom invert
A defined storage depth
One or more side wall slopes
A tie-in to surrounding finished grade
Level AI adjusts the invert elevation to satisfy the governing constraints (volume, depth, invert control, or drainage limits). A feature line is returned for the lip and the shape is defined by cogo points .
Settings (Defaults in web)
Setting | Description |
Target volume | If enabled, applies this target volume to all ponds created in your DWG |
Target depth (minimum and maximum) | If enabled, applies this target depth to all ponds created in your DWG |
Target grade | If enabled applies up to 3 different grades of the ponds side slopes (from edge). e.g. If want just a single grade, only specify Grade 1 and leave Grade 1 distance blank, if want to grades, set Grade 1, Grade 1 distance and Grade 2 (leaving Grade 2 distance blank). |
Settings (On Pond Feature)
Click on the ponds extended data to set the sizing and grading for each individual pond.
Sizing
There are several ways to size a pond, by a fixed depth or by a target volume.
Setting | Description |
Min Depth | Minimum depth of the pond, leave blank if using volume target |
Target Depth | Used along with Min Depth to determine the depth of the pond. |
Target Volume | If not using a target depth can set a target volume on each pond. |
Grading
You can also put additional grading restrictions on the pond area to control total earthworks allowed.
Setting | Description |
Max Cut | Maximum amount of cut allowed in area, leave blank to ignore. |
Max Fill | Maximum amount of fill allowed in area, leave blank to ignore |
Min Lip Level | Minimum elevation of the lip of the pond. |
Min Invert | Minimum elevation of the bottom of the pond. |
Side wall Grade and distance | Specify up to 3 different side wall grades and distance (from pond edge) for each pond. |
Drainage
Setting | Description |
Maximum catchment area | Used by Service AI to delineate catchments. This is the total area allowed to drain into the pond. |
Max catchment area (impervious) | Used by Service AI to delineate catchments. This inspects the area Impervious regions in the project. Node road lanes are automatically assigned impervious regions. |
Max catchment area flow | Used by Service AI to delineate catchments. |