Drainage Run Checker & As-built Pack
Check pipe falls, gradients, cover and approximate quantities across a multi-point drainage run, then export an editable CSV or professional PDF report.
1. Project and report details
2. Design criteria and quantity settings
Cover is calculated vertically from finished ground level to the pipe crown. Quantity outputs are preliminary estimates and must be checked against the specification and measured trench geometry.
3. As-built drainage points
Enter points in increasing chainage order. Levels and chainages are in metres; pipe diameter is in millimetres.
| Point | Chainage (m) | Ground RL (m) | Invert RL (m) | Ø (mm) | Note | Remove |
|---|
Drainage Run Report
Segment checks
| Segment | Length | Fall | Gradient | Slope | Start / end cover | Status |
|---|
Point schedule
| Point | Chainage | Ground RL | Invert RL | Ø | Cover | Check | Note |
|---|
Quantity estimate
Checker notes
How to use the drainage run checker
- Enter the report author, company, project and drainage-run reference.
- Set the required minimum cover and limiting gradient, plus optional trench quantity assumptions.
- Add each chamber, pipe end or surveyed point in increasing chainage order.
- Enter finished ground level, pipe invert level and diameter at every point.
- Select Check drainage run to review every segment and the overall run.
- Correct or annotate flagged data, recalculate, then export CSV or print the report to PDF.
Calculation method
For each segment, fall equals upstream invert minus downstream invert. Gradient is reported as 1 in X, where X equals horizontal segment length divided by fall. Cover equals ground level minus pipe crown level; pipe crown equals invert level plus outside diameter. The checker flags adverse or flat runs, gradients flatter than the selected limit, insufficient cover and inconsistent chainage.
Frequently asked questions
Can this replace a drainage design or hydraulic calculation?
No. It checks surveyed or entered geometry. Pipe capacity, self-cleansing velocity, surcharge, rainfall and network hydraulics require an appropriate drainage design.
What level should be used for cover?
Use the applicable finished ground, road or formation level required by the project specification. The calculator measures cover to the pipe crown.
Can the report contain several manholes or pipe sections?
Yes. Add as many ordered points as needed. Every adjacent pair is checked as a separate segment and included in the same report.
How do I save a PDF?
After calculating, choose Print / Save PDF and select the browser’s Save as PDF destination. Add the author and company before printing so they appear in the report.
Related online construction tools
Use the reduced level calculator, slope and gradient calculator or return to all online surveying and engineering tools.