HydraStorm provides several ways to edit pipe geometry and properties, from single-pipe adjustments to multi-pipe operations that set continuous slopes across an entire alignment run. All edits update the profile view and hydraulic results in real time, giving you immediate feedback on the impact of your changes.
Select a pipe by clicking it in the profile view or by clicking its row in the results grid. The following properties are directly editable in the results grid or property panel.
| Property | Description |
|---|---|
| Inv US | Upstream invert elevation (ft). Edit directly and the profile updates live. |
| Inv DS | Downstream invert elevation (ft). Edit directly and the profile updates live. |
| Slope % | Pipe slope as a percentage. When you edit slope, HydraStorm holds the downstream invert fixed and recomputes the upstream invert. |
| Size | Dropdown of available sizes from the active part family. Only sizes present in the Civil 3D parts list for that pipe's part family are shown. For circular pipes, sizes are in inches; for box pipes, sizes are in feet (W × H). |
| Part Family | Change the pipe material and type (e.g., RCP, HDPE, CMP). Changing the part family updates the available sizes in the Size dropdown. |
| Manning's n | Friction coefficient for the pipe. Defaults to the project-wide value, but can be overridden per pipe. |
| Q (local flow) | Local design flow (cfs) at the upstream node of this pipe. Leave blank or set to 0 for nodes with no local inflow. |

The available pipe sizes in HydraStorm come directly from the Civil 3D parts list assigned to your pipe network. If your parts list includes 18", 24", 30", and 36" RCP, those are the only sizes in the dropdown. This ensures every size you select in HydraStorm can be written back to Civil 3D. To add more sizes, update the parts list in your Civil 3D drawing.
Raise/Lower shifts both endpoints of the selected pipe(s) by a uniform vertical offset. Enter a positive value to raise or a negative value to lower. This adjusts depth without changing slope.
Access via the right-click context menu or Ctrl+Shift+R.

Set Slope applies a specific slope percentage to the selected pipe(s). Choose which end to anchor:
Access via the right-click context menu or Ctrl+Shift+L.
The Match to Adjacent commands align a pipe's endpoint to the neighboring pipe's geometry at the shared junction. Right-click a pipe and choose from the Match to Adjacent submenu:
| Command | Description |
|---|---|
| Invert DS | Sets the selected pipe's downstream invert to match the downstream neighbor's invert at the shared junction. |
| Invert US | Sets the selected pipe's upstream invert to match the upstream neighbor's invert at the shared junction. |
| Crown DS | Adjusts the downstream invert so the pipe's crown matches the downstream neighbor's crown. Prevents surcharging at size transitions. |
| Crown US | Adjusts the upstream invert so the pipe's crown matches the upstream neighbor's crown. |
| Centerline DS | Adjusts the downstream invert so the pipe's centerline matches the downstream neighbor's centerline. Accounts for diameter differences. |
| Centerline US | Adjusts the upstream invert so the pipe's centerline matches the upstream neighbor's centerline. |
These are especially useful after changing pipe sizes — matching crowns or centerlines adjusts the invert to maintain a smooth transition at size changes.
Select contiguous pipes in the results grid using Shift+Click or by clicking and dragging across rows. When multiple pipes are selected, additional editing operations become available for setting continuous slopes across the entire selection.
The Match Criterion dropdown controls how junction transitions are handled when applying a continuous slope across multiple pipes:
The Anchor dropdown controls which end of the selection is held fixed:
Match Slope (Ctrl+M) computes a continuous slope across the entire selection. It interpolates intermediate junction inverts using the selected match criterion and anchor point to produce a uniform grade from one end to the other.
Raise/Lower applies uniformly to all selected pipes. Every upstream and downstream invert in the selection is shifted by the same amount.
Right-click a pipe in the profile view or results grid for quick access to editing commands:
The results grid supports Excel-like keyboard navigation for fast data entry:
| Key | Action |
|---|---|
| Tab | Move to the next editable cell (wraps to next row) |
| Shift+Tab | Move to the previous editable cell |
| Enter | Stay in the same column, move to the next row within the alignment |
| F2 | Enter edit mode on the current cell |
| Left / Right Arrow | Select previous / next pipe in the alignment |
Every edit is tracked in the undo history:
The undo stack covers all property changes including invert elevations, pipe sizes, Manning's n overrides, flow entries, and loss type assignments.
Note: Changes you make in HydraStorm are not written to Civil 3D until you click Apply to C3D. Use Discard to revert all changes since the last Apply.