VectorExpertCivilSurvey Expert turns a survey of a tank's bed and bund into contours, the capacity and water spread at every level up to the full tank level, and the desilting quantity against the bed level. The capacity plan prints with its table, the area–capacity curve and your title block.
On the plan
The tank, in plan
The Village tank in the sample has its inner toe surveyed as points coded TOE and the top of its bund as points coded TOB. Water rises inside the boundary to the full tank level; above the boundary's lowest point it would spill.
Schematic plan, made-up levels.
- Bed
- The tank bed, contoured from the survey. The capacity table starts from its lowest point.
- Boundary
- The inner toe of the bund, joined from its points; or the top of the bund, drawn for one result.
- Water at the FTL
- Shaded on the plan, with its edge drawn as the FTL contour.
- Bund
- Contours of both faces of the bund, and sections across it along the TOB points.
The job, start to finish
A tank job, step by step
Each step links to the full details of that part of the Contour screen.
- 01
Import the survey
Import the points of the bed, the toe and the bund. The TIN and the contours are drawn at once.
- 02
Set the boundary
Join the inner toe by its code (TOE in the sample), or draw a boundary along the top of the bund.
- 03
Capacity to the FTL
Type the FTL and the step. The capacity in m³ and ML and the water spread show as you type, with a warning if the water would spill.
- 04
The desilting quantity
A volume against the bed level gives the silt to be removed, inside the same boundary.
- 05
Sections across the bund
Join the TOB points as the alignment and take a section every 10 m, or run a profile across the tank.
- 06
Print the capacity plan
The water at the FTL, the CAPACITY table and the area–capacity curve, with your title block, on A3, A2 or A1.
What you hand over
From one project file
| Output | What it holds |
|---|---|
| Capacity plan | The water at the FTL, the FTL contour, the CAPACITY table, the area–capacity curve, notes and your title block. PDF or print. |
| Capacity sheet | Level, water spread, volume of the step and capacity in m³ and ML, the FTL row in bold, in Excel. |
| Desilting quantity | Cut and fill against the bed level, with the Grid levels, Cut-Fill by cell and Summary sheets. |
| Sections and profile | Sections across the bund as a CSV or a route, and a profile across the tank drawn under the plan. |
| AutoCAD drawing | DXF or DWG with the contours, the water on WATER and its edge on FTL_CONTOUR. |
Common questions about tanks and ponds
How is the tank capacity worked out?
At each level, the volume below that flat level inside the boundary, worked out on the TIN. It is exact for the surveyed surface, with no rule between levels.
What boundary should a tank have?
Usually the inner toe of the bund, surveyed as points of one code. To work out the capacity up the inner face of the bund, draw a boundary along its top for that result.
What if the full tank level is above the bund's lowest point?
The dialog warns that the water would spill there, and the warning goes in the checks strip and on the printed plan.
Can I get the tank capacity in ML?
Yes. The capacity is given in m³ and in ML at every level, with the water spread in m².
Can it give the desilting quantity?
Yes. A volume against the bed level, inside the tank's boundary, gives the quantity of silt, with its sheets for Excel.