Experimental River Model

Quick Answer: The Experimental River Model is a stream table: a sloping tray of sand or sediment with water running across it, used in geography and earth science to show how rivers erode, transport and deposit material and form meanders and deltas.

How a Stream Table Models a River

In an experimental river model, water enters at the upper end of a tilted tray of sediment and flows to an outlet at the lower end. Within minutes the flow cuts a channel, carries grains downstream and drops them where the water slows. Students watch in real time what takes rivers thousands of years: bends migrating into meanders, sand bars building on inside bends, and a delta spreading where the channel meets still water.

Two controls drive most investigations: the slope of the tray and the discharge, meaning the volume of water flowing each second. Steeper slopes and higher flows raise velocity and erosion; gentle slopes and low flows favour deposition and meandering. Grain size matters too, since fine sand moves more easily than gravel, so a mixed sediment shows sorting along the channel.

The listing does not describe the tray size, the sediment supplied or how water is fed and returned, whether from a tap, a header tank or a recirculating pump. Those details decide where the model can be set up in a school, so they are worth settling before ordering.

Specifications

River Investigations

• Showing the three stages of river work: erosion upstream, transport, and deposition downstream
• Measuring how slope or discharge changes channel shape and delta size
• Modelling a flood by briefly increasing the flow
• Testing how a barrier, such as a model dam or bank protection, changes erosion downstream

Setting Up and Cleaning

• Place the model on a level, waterproof surface near a sink or drain, with a bucket or tank at the outlet.
• Pre-wet the sediment before starting so the first flow runs over the surface instead of soaking in.
• Let sediment settle in the catch tank and reuse it; washing sand down the drain can block pipes.
• Dry the tray and sediment fully before storage to prevent mould and corrosion of any metal parts.

Why Choose LabEquip

Geography departments and earth science teachers use river models to make fluvial processes visible within a single lesson. LabEquip lists this model in General Lab Products, other demonstration models are grouped under educational science models, and set-up details can be confirmed through the contact page.

Frequently Asked Questions

What is a stream table?

A stream table is a tray of sediment set at a slope with water flowing across it. It models a river on a small scale so that erosion, transport and deposition can be watched and measured in a lesson.

Why do meanders form in the model?

Water flows faster on the outside of a bend, eroding the bank, and slower on the inside, where sediment is deposited. Over time the bends grow and shift, as they do in real rivers on gentle slopes.

How does changing the slope affect the river?

A steeper slope makes the water flow faster, so it erodes more and cuts a straighter, deeper channel. A gentle slope slows the flow, encouraging deposition, wider channels and meandering.

What sediment works in the model?

Fine to medium sand is commonly used because it moves at modest flows. Mixing in some coarser grains or a little clay shows sorting and firms the banks slightly, so channels hold their shape longer.

How can students record results?

Photograph the channel from above at fixed intervals, measure channel width and delta length with a ruler, and time a floating object over a known distance to estimate surface velocity.

How does the model differ from a real river?

The scale is tiny, the flow is steady and the sediment is uniform, so features form quickly and simply. Real rivers have floods, vegetation and varied rock, which makes a useful discussion about the limits of any model.

Last Updated: September 2026