---
title: "Kinematic Wave"
canonical: "https://help.innovyze.com/space/infodrainage2020v2/16416886/Kinematic%20Wave"
format: markdown
---
### Parameters

**Flow Length - **The length of the Sheet flow path.

**Land Slope - **The slope of the hydraulic grade line.

**Event Intensity - **The intensity of the rainfall.

**Catchment Roughness - **Horton’s Roughness value.


### Calculation

![image](media://b1893470-0aeb-408f-a6f9-586254eb477a)


where:

<span style="color: #707070">L  = Length of overland flow (m)</span>

S = Average catchment slope (m/m)

i  = Rainfall Intensity (mm/hr)

n  = Surface roughness (similar but not identical to Manning’s n)

Concrete or Asphalt 0.010 - 0.013

Bare Sand 0.010 - 0.016

Graveled Surface 0.012 - 0.030

Bare Clay-Loam Soil (eroded) 0.012 - 0.033

Sparse Vegetation 0.053 - 0.130

Short Grass Prairie 0.100 - 0.200

Lawns 0.170 - 0.480

<span style="color: #707070"> </span><span style="color: #707070">t</span><sub>c </sub><span style="color: #707070">= time of concentration (hrs)</span>