Unit Hydrograph Peak Calculator
Actual independently calibrated unit-hydrograph peak/ties plus integrated unit-runoff volume over unequal times, no rational-method peak alias. Caller independently establishes units, regime, calibration and applicability; this does not establish design-code compliance, authenticity, operational safety, treatment efficacy or a validated forecast.
Description
A unit hydrograph describes discharge response on an explicitly stated rainfall-depth basis.
A unit hydrograph describes discharge response on an explicitly stated rainfall-depth basis.1
Sampled peak and trapezoidal volume depend on time resolution and observation coverage. Use this tool to calculate unit Hydrograph Peak from the supplied measurements and assumptions.
When to use Unit Hydrograph Peak Calculator
Use this tool to calculate unit Hydrograph Peak from the supplied measurements and assumptions. Establish the SI units or caller unit basis, load signs, measurement interval, model conditions and independently chosen coefficients or references.
How to use Unit Hydrograph Peak Calculator and understand its results
- Establish the SI units or caller unit basis, load signs, measurement interval, model conditions and independently chosen coefficients or references.
- Enter callerUnitHydrographTimesHours, callerUnitHydrographFlowM3SecondPerMm, using the field meanings and rules below, then run the tool.
- Read sampledUnitHydrographPeakTimesHours, sampledUnitHydrographPeakM3SecondPerMm, hydrographIntegratedM3PerMm. Interpret the fields using their units, signs and evidence conventions below.
- If input validation fails, correct the reported field and run again. Before applying the result, check reference scope, model assumptions and any missing evidence or placeholder values.
| Input field | Meaning | Value type | Requirement |
|---|---|---|---|
| callerUnitHydrographTimesHours | Caller unit hydrograph times hours | list of number | Required |
| callerUnitHydrographFlowM3SecondPerMm | Caller unit hydrograph flow m3 second per mm | list of number | Required |
Enter at least two strictly increasing nonnegative time samples in hours and aligned nonnegative discharge per mm of runoff in m³/s/mm. Return maximum sampled discharge and every equal-maximum time, plus trapezoidal time integral multiplied by 3600. This is a sampled peak and volume in m³/mm; no hydrograph fitting or rainfall convolution is performed.
peak=max(q_i); volumeM³/mm=3600×ΣΔtimeHours×(q_i+q_(i+1))/2 Use the exact units, boundary rules, ordering and missing-evidence conventions above.
| Output field | Meaning | Value type |
|---|---|---|
| sampledUnitHydrographPeakTimesHours | Sampled Unit Hydrograph Peak Times Hours; follow the units, sign, ordering and evidence convention stated above | list of number |
| sampledUnitHydrographPeakM3SecondPerMm | Sampled Unit Hydrograph Peak M3 Second Per Mm; follow the units, sign, ordering and evidence convention stated above | number |
| hydrographIntegratedM3PerMm | Hydrograph Integrated M3 Per Mm; follow the units, sign, ordering and evidence convention stated above | number |
{
"input": {
"callerUnitHydrographTimesHours": [
0,
1,
3
],
"callerUnitHydrographFlowM3SecondPerMm": [
0,
2,
0
]
},
"output": {
"sampledUnitHydrographPeakTimesHours": [
1
],
"sampledUnitHydrographPeakM3SecondPerMm": 2,
"hydrographIntegratedM3PerMm": 10800
}
}Limitations and assumptions
Sampled peak and trapezoidal volume depend on time resolution and observation coverage. Interpretation depends on the units, sampling scope and exact model described above.
All listed fields require explicit values. Unexpected fields, incorrect types, nonfinite numbers and sparse evidence arrays fail validation; the specific bounds and alignment requirements are stated above. Extremely large inputs or outputs can also be rejected. An input error is distinct from a successful result reporting false, no matches or missing evidence.
Alternative or Complementary methods
Use Snyder Unit Hydrograph Calculator for this related task: Snyder-style hydrograph relations use basin dimensions and calibrated coefficients.
Use Muskingum Flood Routing Calculator when its separate inputs and assumptions fit the question: Muskingum routing uses a storage-time parameter and weighting to advance an outflow sequence.
References
-
Unit Hydrograph Peak Calculator — tool.io
Similar or alternative tools
- Snyder Unit Hydrograph Calculator
Snyder-style hydrograph relations use basin dimensions and calibrated coefficients.
- Muskingum Flood Routing Calculator
Muskingum routing uses a storage-time parameter and weighting to advance an outflow sequence.