Review warnings indicate where parts of the design may have issues for a Service AI or Level AI run. There is additional data attached to the cogo review point (extended data property set) and panorama event log.
Priority can be from 1 (lowest) to 9 (highest). In general priorities < 4 are for information, priorities 4-8 are warnings (can affect Level AI / Service AI run) and 9 are errors (will affect Level AI / Service AI run and must be resolved before proceeding).
Validation code | Explanation | Steps to resolve |
NoServicingExtent | No servicing extent polygon is present in the project, Service AI requires this to be defined. | Add a valid servicing extent polygon to define the area for servicing design. |
ServicingExtentNotInSurface | Servicing extent is not fully within the Existing surface | Adjust the servicing extent polygon so it is completely within the surface extent or increase the size of the existing surface. |
OlfpTooCloseToBuilding | OLFP (Overland Flow Path) is too close to a building | Move the OLFP away from building footprints to maintain required separation |
InvalidBaselineType
Summary: The corridor baseline isn’t a valid Alignment/FeatureLine (or it’s missing/corrupted).
Most common causes
Baseline alignment was deleted/renamed, or data shortcut/reference broke.
You’re accidentally using unsupported geometry in a place that expects an alignment-based workflow (especially around intersections).
Resolution
In Corridor Properties → Baselines, confirm the baseline object is a real Alignment (or valid FeatureLine where applicable) and still exists.
If it’s missing/broken: reselect the correct alignment, or recreate it (and re-add it as a baseline).
Re-check the “Quick checklist” (profiles, regions, design vertical baselines), then rebuild the corridor.
Run Validate Corridor to confirm the corridor meets requirements.
CorridorRegionOverlap
Summary: Corridor regions overlap spatially (often leads to bad surfaces/quantities and unstable rebuilds).
Most common causes
Region station ranges overlap after edits/splitting.
Alignments overshoot into intersections or past cul-de-sac ends.
Resolution
Locate the review point related to find the regions overlapping and in Corridor Properties → Parameters → Regions, review the region’s Start/End station and remove overlaps (adjust extents or split cleanly).
Confirm centerline alignments are trimmed correctly at dead-ends/intersections (no overrun).
Rebuild corridor, then Validate Corridor.
MissingRegionTarget
Summary: A required target (alignment/profile/feature line) isn’t assigned for a region.
Most common causes
Targets weren’t mapped after adding/changing a region or assembly.
Cul-de-sac/knuckle/intersection targets not set to the intended centerline(s).
Resolution
Open Target Mapping for the corridor/region and assign the missing target(s) (alignment/profile as required).
If it’s an intersection/curb return context: ensure you’re following the supported approach (offset alignments/curb returns; feature lines aren’t supported for defining curb returns).
Rebuild corridor and validate.
InvalidRegionSubassemblyInsertionPoint
Summary: The region’s subassembly insertion point doesn’t match what the workflow expects.
Most common causes
Intersection/curb return assemblies created with the wrong insertion point.
Knuckle/curb type mismatch (e.g., Back of Curb vs Gutter Edge) with inconsistent setup.
Resolution
Inspect the assembly and confirm the insertion point matches the supported workflow for that feature.
For intersections created manually, Allsite notes using “Gutter Edge” insertion point for curb return subassemblies (Civil 3D default).
Rebuild corridor and validate.
InvalidAssembly
Summary: The assigned assembly is invalid for the region (unsupported, missing, or not appropriate).
Most common causes
Using custom combined subassemblies (not currently supported).
Assembly deleted/renamed, or contains parts not suitable for that region type.
Resolution
Replace the region’s assembly with a standard, supported assembly (avoid custom combined subassemblies).
Confirm the assembly exists and is assigned to the correct region(s).
Rebuild corridor and validate.
InvalidRegionSubassembly
Summary: A required subassembly is missing/invalid inside the assembly.
Most common causes
Curb return assemblies missing required components (e.g., lane subassembly).
Subassembly settings/targets aren’t set after edits.
Resolution
Edit the assembly and confirm all required subassemblies exist and are configured correctly.
For curb returns, Allsite notes a lane subassembly is required (used to extend mesh lines toward the target alignment).
Rebuild corridor and validate.
InvalidCulDeSac
Summary: Marked as a cul-de-sac but doesn’t meet geometric/target requirements.
Most common causes (per the supported definition)
Main road alignment doesn’t end/start at the cul-de-sac center.
Cul-de-sac alignment isn’t set up with the expected station/region/target relationships.
Using the main road alignment as the cul-de-sac baseline (explicitly not supported).
Resolution
Confirm the cul-de-sac is at a road end and the main road alignment ties to the center as required.
Confirm the cul-de-sac region setup follows the described rules (baseline/region association + targets).
Ensure the cul-de-sac target is set to the Main Road Alignment and curved to the center.
Rebuild corridor and validate. assigned.
InvalidGeometry
Summary: Region geometry is invalid (self-intersections, zero length, broken links, etc.).
Most common causes
Alignment overshoot/poor trimming at ends/intersections.
Intersections created before meeting prerequisites (design profiles + vertical baselines), causing unstable profile/curb-return link behavior.
Secondary road profile rules / locked PVIs interfering with automated updates (Allsite notes these should be disabled/unlocked before running results).
Resolution
Fix obvious geometry problems first (trim alignments; remove tiny/zero-length regions; correct overlaps).
Re-apply the prerequisites (EG+Design profiles, regions, design vertical baselines), then recreate affected intersections if needed.
Disable unsupported profile rules / unlock ruled locked PVIs where applicable.
Rebuild corridor and validate.
UnsupportedTarget
Summary: The assigned target type isn’t supported for this region/subassembly (or the target object is incompatible / broken), so Civil 3D (and Allsite) can’t resolve it reliably.
Common causes
Target is the wrong kind according to allsite requirements.
Target object was deleted/renamed, is a data shortcut that isn’t resolved, or is out of date.
Intersection / curb return context where the workflow expects offset alignments / curb return alignments and not a different geometry type.
Resolution
Open Corridor Properties → Parameters → Targets(or region target mapping) and identify which target is flagged.
Replace it with a supported target for that subassembly:
Horizontal targets: Alignment (typically the correct one for that region, including offset/curb return alignments where applicable).
Vertical targets: Ensure the required profile exists (EG + Design) and the region is using the intended design setup.
If this is near an intersection/cul-de-sac/knuckle: confirm the setup matches the supported workflow (trim alignments correctly; use regions; set design vertical baselines before creating intersections).
Rebuild the corridor, then run Allsite → Validate Corridor to confirm the issue is resolved.
NoRoadsInPackage
Description: Level AI prepare was run, but no corridors exist / no simple roads are in the model. In some circumstances, it can be due to an error where data could be extracted from DWG for road corridors.
Resolution: Ensure either road corridors have been correctly created or simple road corridors using Layout Assist.
AlignmentOverrun
Description: Side-road alignment continues past junction, crossing the mainline at the T-intersection.
Resolution: Edit side-road geometry so its end PI meets the mainline, then rebuild corridors.
MultipleCurbRegions:
Description: Curb return alignment has multiple regions; only one region is supported.
Resolution: Set curb return to a single region; add intersection stations via Region Frequency if needed.
NoCorridorsFound
Description: No corridors were detected in the project and no Allsite simple roads were detected.
Resolution: Follow steps to set up the project, there are 3 methods for creating roads that are supported
NoCoordinateSystem
Description: No coordinate system was defined on the DWG, this is required for Allsite to geolocate the project.
Resolution: Add a coordinate system using MAPCASSIGN
NonZeroCenteredSubAssembly
Description: The central sub assembly is offset from the Assembly itself, this is not supported and will lead to a minor discrepancy in the resulting levels.
Resolution: Move the central sub assemblies to be snapped to the Assembly origin.
CorridorRegionGap
Description: A gap in road corridors has been detected, this will affect corridor generation. Ignore if using simple road centrelines instead of civil 3d intersections / knuckles.
Resolution: Close the gap between regions
CurbNotAdjacentToLane
Description: A curb subassembly is not adjacent to a lane sub assembly. Allsite requires usage of lane sub assemblies as these are used for data extraction so this could affect the corridor data integrity.
Resolution: Change to a lane subassembly.
LaneNotAdjacentToCurbGutter
Description: A lane isn't adjacent to a curb gutter. Allsite only allows lane sub assemblies to be used for vehicle lanes. Lanes are used for data extraction so this could affect the corridor data integrity.
Resolution: Change any sidewalk sub assemblies to appropriate alternatives.
NoLayersCustomSubAssembly
Description: A custom subassembly is in use with geometry that cannot be read.
Resolution: Replace with standard Civil 3D subassembly.
ConditionalSubAssemNotSupported
Description: A conditional subassembly was detected, these are not supported in Level AI
Resolution: Remove the subassembly
CurbSubAssemblyNotCentered
Description: A curb subassembly is not centred at its origin, this can cause slight discrepancies in Level AI levels.
Resolution: Adjust so the subassembly is centred at its origin.
CustomSubAssembly
Description: A custom subassembly can cause issues with data extraction.
Resolution: Replace with standard Civil 3D subassembly. If require usage of custom sub assemblies, ensure the custom sub assembly name has the word "Lane" (for custom lane sub assemblies) and "Curb" (for custom curb sub assemblies) or "Sidewalk" (for custom sidewalk assemblies).
DaylightingNotRequired
Description: A daylighting subassembly was detected. These are not required and are ignored in Level AI runs.
Resolution: Remove the subassembly.
AlignmentLoop
Description: Road alignment is looping back on itself, this causes issues when using the Civil 3d intersection tool.
Resolution: Remove any self-intersections or loops from the road alignment geometry.
RdAlignmentHasLoops
Description: Road alignment is looping back on itself, this causes issues when using the Civil 3d intersection tool.
Resolution: Remove any self-intersections or loops from the road alignment geometry.
NoSubassemblyType
Description: Layout assist has been run, but no subassembly has been assigned to generated curb modifiers.
Resolution: If not already in the model, add an assembly. Then refresh the property data set schema with command "UpdateAllsiteSchema". You can then select all the curbs (use property data select with attribute 'Is outside modifier' set to false)
SurfaceLocationMismatch
Description: The surface data is located far from the expected project location, indicating the coordinate system (EPSG) is likely incorrect.
Resolution: Verify the coordinate system using the MAPCSASSIGN command and confirm it matches your site location using a geolocation basemap.
InvalidSurface
Description: The selected surface is missing, has no triangles, is too dense, or is incorrectly referenced and cannot be processed.
Resolution: Rebuild the surface in Civil 3D (right-click → Rebuild), ensure it is correctly selected in project settings, and verify it contains valid triangle data.
NoPipesInPackage
Description: No stormwater or wastewater pipe networks were found in the project, which are required to run Service AI.
Resolution: Ensure pipe networks are created and visible in Civil 3D before running Service AI.
LotGradeNoType
Description: A parcel has been created that has grade restrictions but does not have a 'Parcel Category' assigned. This can result in the incorrect Level AI behaviour when grading the parcel. See explanation of different parcel types here.
Resolution: Add a category to the parcel.
OlfpNotTouchingRdCenterline
Description: OLFP does not touch a road centerline.
Resolution: Ensure the OLFP crosses or touches a road centerline to inform the system of the low point.
RoadCenterpointTooCloseToRetainingWall
Description: Road centerpoint (end of road corridor region / simple centerline) is within 3ft of a retaining wall, this can affect design.
Resolution: Pull the road region/centerline back from the wall or shift the wall.
RoadCenterpointTooCloseToBuilding
Description: Road centerpoint (end of road corridor region / simple centerline) is within 3ft of a building
Resolution: Add a building tie-in or pull the road region/centerline back from the building
RdCenterlineHasLoops
Description: Road centerline geometry contains loops.
Resolution: Edit the centerline geometry to remove self-intersections or loops.
RdRegionNotInEWExtent
Description: Road region is not within the earthworks extent, this can cause parts of the profile with zero elevation after a Level AI run.
Resolution: Adjust the road region geometry so it fits entirely within the earthworks extent.
RdAlignCenterlineNotSnapped
Description: Road alignment centerline is not snapped to another road alignment centerline.
Resolution: Snap the endpoints of the road alignment centerline to connect with other centerlines as required.
BuildingTooSmall
Description: A building polygon has an area smaller than the minimum threshold (10m² / ~108ft²), suggesting it is not a valid building footprint.
Resolution: Remove the building or redraw it with the correct extents.
BuildingOverlap
Description: Two or more building polygons overlap each other, which will cause conflicts in design processing.
Resolution: Adjust the building footprints so they do not overlap.
BuildingNearEarthworksExtent
Description: A building is within 1m of an earthworks extent boundary, which may cause grading conflicts.
Resolution: Move the building further from the earthworks extent boundary (at least 1m/3ft clearance).
BuildingOverlapsRoad
Description: A building polygon overlaps a road extent, which is an invalid configuration that will cause design failures.
Resolution: Move or reshape the building or road extent to eliminate overlap.
BuildingNearRoadExtent
Description: A building is within 1m/3ft of a road extent boundary, which may cause grading conflicts.
Resolution: Move the building further from the road extent boundary (at least 1m clearance).
BuildingOverlapsRoadParcel
Description: Building polygon overlaps with a road parcel (e.g., PUBLIC ROAD, JOAL, COAL, CARPARK).
Resolution: Adjust the building or parcel geometry to remove the overlap.
BuildingNotWithinParcel
Description: A building is not located within any parcel, meaning it cannot be assigned to a lot for servicing and design.
Resolution: Ensure the building is placed within a valid parcel boundary, or add/adjust parcels to cover the building.
BuildingOverlapsRoadParcel
Description: A building polygon overlaps a road parcel, which is an invalid configuration.
Resolution: Move or resize the building so it does not overlap the road parcel.
BuildingTooManyPoints
Description: A building polygon has an unusually high number of vertices relative to its area (area/point_count < 4 and point_count > 16), suggesting a bad geometry conversion from DWG or other CAD format.
Resolution: Simplify the building geometry to reduce the vertex count while maintaining the correct shape. Remove curved building lines / simplify them.
TieInNotTouching
Description: Building tie-in does not touch the building boundary or road centreline.
Resolution: Ensure the tie-in line connects to both the building boundary and the road centreline.
RdCenterlineHasLoops
Description: Processed road centreline has loops in its geometry, this can cause issues to Level AI.
Resolution: Remove any self-intersections or loops from the simple road centreline geometry at intersections.
RdCenterlineNotInRoadExtent
Description: Road centreline is not within the associated road extent.
Resolution: Adjust the centreline geometry so it is contained within the road extent polygon.
RdCenterlineNotSnapped
Description: Road centreline is not snapped to another centreline or required feature.
Resolution: Snap the centreline endpoints to the appropriate features.
RdCenterlineTooShort
Description: Road centreline is shorter than the minimum required length.
Resolution: Extend the centreline to meet the minimum length requirement.
RdCenterlineGap
Description: There is a gap between road centrelines.
Resolution: Connect or extend centrelines to close the gap.
BadEdge
Description: The edge of a polygon is detected as having a sharp angle in it, this can cause issues with a Level AI run. Features that are analysed for bad edges: Earthworks Extent, Corridor Extent (a processed polygon from C3d corridor).
Resolution: Remove any vertexes causing sharp angles in the geometry
RdCenterlineCrossesMultipleRdExtents
Description: A road centreline crosses more than one road extent.
Resolution: Split the centreline or adjust extents so each centreline is within a single extent.
RdCenterlineAngles
Description: Road centreline has angles that are too sharp or do not meet design criteria.
Resolution: Smooth or adjust the centreline geometry to meet angle requirements.
RdCenterlineOverlaps
Description: Road centrelines overlap each other.
Resolution: Adjust the geometries to remove overlaps.
RdCenterlineParallel
Description: Road centrelines are too close and nearly parallel.
Resolution: Increase the separation between parallel centrelines.
ParcelOverlap
Description: Lots/parcels overlap with each other. Sometimes this can be because parcels from an old layout are still present in the project.
Resolution: Adjust lot boundaries to eliminate overlaps or delete old parcels from a previous design.
NormalLotOverRdExtent
Description: A NORMAL category lot overlaps the road corridor by a significant amount. This can cause undesired behaviour.
Resolution: Reduce the size of the road corridor or shift parcel boundaries. If the parcel is not meant to be a NORMAL category lot, change to another category (ie DRIVEWAY / ROAD parcel category)
NoParcelCategory
Description: Parcel does not have a category assigned, this can lead to undesired Level AI grading. This is a fatal warning if less than 10% of the lots are NORMAL type lots.
Resolution: Set the parcel category, use guide provided here.
NormalLotSubTypeSize
Description: A NORMAL lot with a 'Normal lot sub type' is very large, this can cause issues as may add extra drainage lines, this is intended for residential lots only.
Resolution: Remove the normal lot sub type (ie set to 'None'), or change to a different lot category (ie public drainage / public park)
Road parcel (singlepart geometry)
Description: Road parcel geometry is multipart when it should be singlepart.
Resolution: Split multipart geometries into singlepart features.
Building (singlepart geometry)
Description: Building geometry is multipart when it should be singlepart.
Resolution: Split multipart geometries into singlepart features.
OLFP (singlepart geometry)
Description: OLFP geometry is multipart when it should be singlepart.
Resolution: Split multipart geometries into singlepart features.
Retaining Wall (singlepart geometry)
Description: Retaining wall geometry is multipart when it should be singlepart.
Resolution: Split multipart geometries into singlepart features.
RWNotInEWExtent
Description: Retaining wall is not within the earthworks extent.
Resolution: Adjust the retaining wall geometry to fit within the earthworks extent.
RWOverlaps
Description: Retaining wall overlaps another wall.
Resolution: Adjust wall geometries to remove overlaps.
RWUnderBuilding
Description: Retaining wall overlaps a building. It is OK for a wall to run exactly along a wall, but not under it.
Resolution: Ensure the wall is exactly snapped to the building edge.
RWNotSnapped
Description: Retaining wall is not snapped to the earthworks extent.
Resolution: Snap the wall endpoints to the earthworks extent boundary.
RWBadAngles
Description: Retaining wall has angles that are too sharp or do not meet design criteria.
Resolution: Adjust the wall geometry to smooth out sharp angles.
RWTooClose
Description: Retaining walls are too close to each other.
Resolution: Increase the separation between retaining walls.
Road Extent (singlepart geometry)
Description: Road extent geometry is multipart when it should be singlepart.
Resolution: Split multipart geometries into singlepart features.
NoRoadExtents
Description: No road extents detected in processed data. This usually means extraction of roading data from the Civil 3D model was not successful or had issues.
Resolution: If using corridors this usually means the corridor extraction failed, check corridor review points for gaps / overlaps. If using simple roads it usually means there are issues with the modifiers, check that layout assist was run successfully and all modifiers have extended data attributed to them. If using manually drawn modifiers in intersections, ensure they have "Outside road edge" set to true.
RoadExtentOverlaps
Description: Road extent overlaps another road extent.
Resolution: Adjust road extent polygons to remove overlaps.
RoadExtentTooSmall
Description: Road extent area is too small.
Resolution: Increase the area of the road extent polygon.
PondRoadClose
Description: Pond is close to a road corridor / road parcel, if the pond is large this can cause grading issues (as lip of pond must be flat).
Resolution: Ensure space between pond and road, or add a grade break between the pond and road.
PondRoadOverlap
Description: Pond is overlapping a road corridor / road parcel.
Resolution: Adjust the lip of the pond so a gap to allow for grading between road and pond edge.
RoadExtentWidth
Description: Road extent width does not meet minimum requirements.
Resolution: Adjust the road extent geometry to meet width requirements.
RoadExtentNotInEWExtent
Description: Road extent is not within the earthworks extent.
Resolution: Adjust the road extent polygon to fit within the earthworks extent.
LongRdExtentCloseBuilding
Description: A road extent is very close to a building, this can cause issues in the model with viability.
Resolution: Add a building tie-in along the edge of the building and snap the corridor / centreline to it.
Building (overlapping shapes)
Description: Building overlaps with another building.
Resolution: Adjust building polygons to remove overlaps.
Building (too small)
Description: Building area is too small.
Resolution: Increase the area of the building polygon.
Lot (too small)
Description: Lot area is too small.
Resolution: Increase the area of the lot polygon.
Lot (singlepart geometry)
Description: Lot geometry is multipart when it should be singlepart.
Resolution: Split multipart geometries into singlepart features.
Earthworks (overlapping shapes)
Description: Earthworks extents overlap each other.
Resolution: Adjust earthworks polygons to remove overlaps.
Earthworks (slither)
Description: Earthworks extent has slivers or holes.
Resolution: Clean up the geometry to remove slivers and fill holes.
Earthworks (bad edges)
Description: Earthworks extent has bad edges or sharp angles.
Resolution: Smooth or adjust the geometry to remove bad edges.
Earthworks (fields)
Description: Earthworks extent is missing required attribute fields.
Resolution: Add or correct the required fields in the attribute table.
RelationshipEndPointsTooClose
Description: Relationship end points are too close to each other.
Resolution: Increase the separation between relationship end points.
RelationshipLoops
Description: There are loops in the relationship network.
Resolution: Remove or correct the relationships to eliminate loops.
LinkDownstreamElevation
LinkUpstreamElevation
Description: The pipe does not have an upstream elevation set within approximately 60ft (20m) of the existing surface, if servicing enabled this can cause constraints on the Level AI model.
Resolution: Update the lid level and
StructureLidLevel
StructureInvertLevel
Description: The structure does not have an lid/invert level set within approximately 60ft (20m) of the existing surface, if servicing enabled this can cause constraints on the Level AI model.
Resolution: Update the structures lid/invert level
NoOLFPInProject
Description: No OLFP in a large project area, for large projects this is considered Fatal and likely an omission from design. For small projects it is a low level warning
Resolution: Add an OLFP feature to a road in the project, crossing a road centreline and EW extent / other road centreline.
OLFPDitchConnectivity
Description: Overland flow path ditches must cross the earthworks extent to activate
Resolution: Extend the OLFP ditch
OLFPConnectivity
Description: Overland flow paths only activate when they cross a road centerline and cross either:
another road centerline (when OLFP connects 2 roads), or
cross the earthworks extent boundary of the site
connect another OLFP
Resolution: Extend the OLFP
NearEwBoundaryNoOlfp
The end of a road / cul-de-sac not connected to a building tie-in and with no OLFP. Ignore if not intended to be a low point.
Resolution: Add an OLFP feature to a road in the project, crossing a road centreline and EW extent / other road centreline.