Applying Changes

How edits flow between HydraStorm and Civil 3D.

Edit Session Model

HydraStorm uses a snapshot/working pattern. When you load a network, it takes a snapshot of the current state. All your edits modify the "working" copy. Nothing changes in Civil 3D until you explicitly apply.

Apply to C3D

Click the Apply to C3D button to write all pending changes back to the Civil 3D pipe network objects. This includes:

  • Pipe invert elevations (upstream and downstream)
  • Pipe sizes (diameter for circular, width x height for box)
  • Manning's n values
  • Part family changes
  • Accepted Auto Design pipe splits (creating the size-change null structure and the new downstream-leg pipe, and shortening the original pipe to its upstream leg)
  • Part renames from Drawing > Rename Parts by Run...
  • Part Descriptions accepted from Drawing > Label Fittings...

Part Renames

Renames are written last in the Apply batch, and a renumber that shifts names along a run (A-4 → A-3 → A-2 …) or swaps two names goes through without colliding with a name already in use. If a rename can't be written, because Civil 3D rejects it or keeps the old name, Apply reports it as a failure naming the part, so an unwritten name never looks as if it had taken.

Fitting Descriptions

Descriptions accepted in the Label Fittings dialog are ordinary model edits like any other property change: undoable, and pending until Apply. Applying writes the new Description text onto each accepted structure's Civil 3D part; a null structure that gets labelled stays a null structure as far as Civil 3D's part type is concerned. See Label Fittings for templates, tracking, and how a hand edit made directly in Civil 3D is handled on the next refresh.

Toolbar showing the Apply to C3D and Discard buttons
Toolbar showing the Apply to C3D and Discard buttons

Native Hydraulic Properties

Alongside geometry, Apply also populates the calculated design storm hydraulic results into each pipe's and structure's native Civil 3D properties, so they're available to Civil 3D's own part list reports and labels:

  • Pipes: HGL Upstream / HGL Downstream, EGL Upstream / EGL Downstream, Flow Rate, Return Period, and Junction Loss, the computed loss at the pipe's upstream structure.
  • Structures: Hydraulic Grade Line and Energy Grade Line (the structure's own HGL/EGL), Flow Rate, and Return Period.

These are written every time you Apply, so they stay in sync with your latest HydraStorm calculation.

Note: A pipe's Upstream and Downstream HGL/EGL values follow the direction water flows, not which end was drawn first, so Civil 3D's own labels and reports show the hydraulically correct end even on a pipe drawn from its downstream end.

Discard

Click Discard to revert all changes since the last Apply (or since loading if no Apply has been done). The working copy reverts to the snapshot.

Undo / Redo

HydraStorm maintains a full undo/redo history for all edits within the working session (Ctrl+Z / Ctrl+Y). This includes:

  • Invert changes (upstream/downstream)
  • Slope adjustments
  • Size changes
  • Manning's n edits
  • Flow overrides
  • Loss type assignments
  • Kj overrides
  • Raise/lower operations
  • Match operations

Apply to C3D is a one-way write operation. If you need to undo after applying, use Civil 3D's own Undo command (the C3D transaction is committed as a single operation).

Tip

Save your HydraStorm project (.hsp) before applying changes to Civil 3D. The .hsp file stores all your settings, flow assignments, and loss type configurations independently from the drawing.