---
title: "1D river simulations - CES tab | Technical Reference"
slug: "ces-tab"
description: "Learn about the CES tab when viewing 1D river results. "
tags: ["1D river modelling", "viewing results"]
updated: 2022-08-05T09:41:19Z
published: 2022-08-05T09:41:19Z
canonical: "help.floodmodeller.com/ces-tab"
stale: true
---

> ## Documentation Index
> Fetch the complete documentation index at: https://help.floodmodeller.com/llms.txt
> Use this file to discover all available pages before exploring further.

# 1D river simulations - CES tab

This tab contains the run options and advanced parameters specific to simulations using the Conveyance Estimation System (CES).

![RiverSimulationsimagesCESimage026.jpg](https://cdn.document360.io/5074bc26-a9ef-4bf4-b1de-a5c6ce628aca/Images/Documentation/RiverSimulationsimagesCESimage026.jpg)

*Roughness mode* enables you to select from the minimum, recommended or maximum roughness values.

The CES advanced parameters are as follows:

<table>    <tbody>      <tr class="Head">        <th>          <p>Parameter</p>        </th>        <th>          <p>Description</p>        </th>        <th>          <p>Default</p>        </th>      </tr>      <tr class="Odd">        <td>          <p>Number of depth intervals</p>        </td>        <td>          <p>Number of depth intervals</p>        </td>        <td>          <p>25</p>        </td>      </tr>      <tr>        <td>          <p>Lateral eddy viscosity</p>        </td>        <td>          <p>Lateral eddy viscosity for main channel</p>        </td>        <td>          <p>0.24</p>        </td>      </tr>      <tr class="Odd">        <td>          <p>Minimum depth</p>        </td>        <td>          <p>Minimum depth used in calculation</p>        </td>        <td>          <p>0.0</p>        </td>      </tr>      <tr>        <td>          <p>Number of vertical segments</p>        </td>        <td>          <p>Number of vertical segments used in integration</p>        </td>        <td>          <p>100</p>        </td>      </tr>      <tr class="Odd">        <td>          <p>Relaxation</p>        </td>        <td>          <p>Relaxation (alter if conveyance calculation does not converge)</p>        </td>        <td>          <p>1</p>        </td>      </tr>      <tr>        <td>          <p>Temperature</p>        </td>        <td>          <p>Water temperature</p>        </td>        <td>          <p>15</p>        </td>      </tr>      <tr class="Odd">        <td>          <p>Maximum number of iterations</p>        </td>        <td>          <p>Maximum number of iterations</p>        </td>        <td>          <p>15</p>        </td>      </tr>      <tr>        <td>          <p>Convergence tolerance</p>        </td>        <td>          <p>Convergence tolerance</p>        </td>        <td>          <p>0.001</p>        </td>      </tr>      <tr class="Odd">        <td>          <p>Wall height multiplier</p>        </td>        <td>          <p>Multiply the height of the section by x to add an extra wall to the sides of the section</p>        </td>        <td>          <p>1.5</p>        </td>      </tr>    </tbody>  </table>