> For the complete documentation index, see [llms.txt](https://water-strategy.gitbook.io/waterstrategy/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://water-strategy.gitbook.io/waterstrategy/modeling-basics/node-types/water-input/catchment-node.md).

# Catchment Node

## General Description

The **catchment node** is an another kind of input node with a fixed inflow. Catchment nodes are often used to represent river or other type of inflow into the system. Any flow defined on them has to flow into the system. 

Ofthen inflow time series (e.g. Pywr dataframes) are defined on the *flow* attribute to represent catchment inflows however other parameters can also be used (e.g. constant, monthly profile etc...).

[API Reference](https://pywr.github.io/pywr-docs/master/api/generated/pywr.domains.river.Catchment.html).

## Primary Attributes

<table><thead><tr><th width="180.33333333333331">Name</th><th width="318">Description</th><th>Required</th></tr></thead><tbody><tr><td>flow</td><td>The amount of water supplied by the catchment node at each timestep</td><td>Required, defaults to 0 if not entered.</td></tr></tbody></table>

## Examples

coming soon...


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