Troubleshooting

Common issues, what they mean, and how to resolve them.

HydraStorm Will Not Open

"HYDRASTORM is not a known command"

The plugin did not load. HydraStorm loads automatically when Civil 3D starts — no manual loading step is required. If the command is unknown:

• Restart Civil 3D if it was running during installation — the autoloader only scans for plugins at startup.
• Confirm the bundle exists at %ProgramFiles%\Autodesk\ApplicationPlugins\HydraStorm.bundle (default install) or %AppData%\Autodesk\ApplicationPlugins\HydraStorm.bundle (if you chose "Install for me only"). If it is missing, re-run the installer.
• Verify you are running Civil 3D 2025 or newer — the bundle does not load into older releases or plain AutoCAD.

Plugin loads but window does not appear

The window may be off-screen on a previously connected monitor. Reset its position by deleting any saved layout state in %LocalAppData%\HydraStorm\ or move the C3D window so the WPF child can re-center.

Calculation Errors

"Network has cycle / loop"

Loops in storm drain networks are not supported. Open the Network Issues dialog (toolbar) to identify the offending pipe. Common cause: a pipe whose From and To structures cross over a confluence creating a circular flow path.

"Did not converge" warning on a pipe

The normal-depth solver could not find a stable depth within the iteration limit. Causes:

• Extreme slope (negative or near-zero) combined with high flow
• Manning's n outside the valid range — check the pipe's friction coefficient
• Pipe size badly undersized for the flow — try Auto Design or upsize manually

If none of the above resolves it, capture a diagnostic bundle (see below) and send it to support — the iteration limit and convergence tolerance are internal engine settings, not currently user-adjustable.

"HGL exceeds rim elevation"

Surcharge has reached or topped a structure rim. The compliance check flags this when HGL Cover (configured in Project Settings) is violated. Resolution: enlarge upstream pipes, increase slope, or adjust the structure rim.

"Loss type produced K outside published table"

HEC-22 / iSWM / municipal loss equations are evaluated dynamically. If the upstream geometry produces a K value the published table can't represent, HydraStorm marks the cell yellow in the Excel export and writes the literal computed loss instead of the lookup. The number is correct — the spreadsheet just can't round-trip it.

Civil 3D Integration

"Apply" silently fails or partially writes

Most often a locked drawing — another command is running or the document is read-only. Check the Civil 3D command line for the underlying error. If a single pipe fails, the rest of the batch still applies; check the calculation messages banner.

HGL labels do not appear in profile view

Confirm the pipe and structure label styles are configured in Project Settings > Output, then run Output ▾ > Apply Label Styles from the toolbar. See Profiles & Labels.

"Network not visible in dropdown"

HydraStorm hides data-shortcut'd networks (typically water/sanitary) from the analysis dropdown to avoid accidentally analyzing them. They are still loaded for crossings detection. To analyze a referenced network, promote it to a local network in Civil 3D first.

HydraLink Integration

"No basins matched to nodes"

Basin names in HydraLink and structure names in C3D differ enough that even fuzzy matching can't bridge the gap. Open the HydraLink import dialog to manually map basins to nodes. The matcher applies a 5-tier strategy (exact → normalized → fuzzy → spatial → manual) — try renaming for cleaner future imports.

"HydraLink file changed"

The watcher detected an edit on disk. Click the prompt to reload, or ignore it if you're staging changes. The reload re-runs basin matching but preserves your manual overrides.

Output

Excel export shows yellow cells

Yellow highlight marks cells where HydraStorm overrode the spreadsheet's formula with a computed literal. This happens when:

• The pipe is in partial (free-surface) flow — friction-loss formulas in the template assume full pipe
• The loss type uses HEC-22 / iSWM / a complex expression that doesn't round-trip through Kj·V²/(2g)

The literal value is the correct hydraulic answer. If you re-edit the spreadsheet, that cell will not auto-recompute.

Excel file fails to open with "file format invalid"

HydraStorm strips macros from the embedded template at save time. If you see this error, send the file to support with the project file (.hsp) attached for diagnosis.

Diagnostic Bundle

For any unresolved issue, run Help > Run Diagnostic (HSDIAG) from the toolbar. This generates a Markdown dump of your project state, network topology, and calculation output. Email the resulting file to support@bezaleldesignlab.com.