From Head to Tail: A RIO-funded upgrade automates and improves safety in the Saint Anthony Falls Lab Main Channel

March 27th, 2026

The Main Channel is one of SAFL’s most popular experimental research facilities. It’s uniquely huge! It’s got a wave generator! Completed in 1938, it’s been running ever since.

What many people don't know about the channel is that, until very recently, it was a huge pain to operate it. Preparing the facility for a single experimental run could take days, and re-calibrating the channel each day was often an athletic and time-consuming feat. Researchers routinely ran from the Flume Floor to the Intake and back dozens of times to check screens, sprayers, and water levels. Calibrating the flow rate could even require deciphering handwritten notes left by professors on post-its.

This has now changed.

With support from RIO's Research Infrastructure Investment Program, SAFL’s Applied Research & Engineering Team completed a comprehensive automation upgrade that makes the Main Channel far easier and safer to operate for both new and experienced researchers.

The team assessed and modernized wiring throughout the facility, installed new sensors, and integrated them into a unified control system. Today, a single student can monitor and adjust a Main Channel experiment from one computer, dramatically reducing the physical effort, guesswork, and risk previously required to run experiments.

Below is a look at the improvements from head to tail of the channel.

Gate House and Headgate

Operations at the upstream end of the channel are now largely automated with flexibility to add more capabilities. The team replaced the headgate’s outdated controls with a modern interface.

The gate elevation system has been automated so that operators can set a desired position once and return to that exact setting reliably each time. No more holding down a physical button and hoping you get the gate close to where you want it. Flow rate and water elevation are now controlled through software rather than through manual adjustments.

A new radar-based river elevation sensor provides accurate, real-time readings which feed into the control system to calculate flowrate.

Remotely operated cameras allow researchers to monitor screens and sprayers without leaving their desk. The system also enables remote screen rotation, eliminating another routine trip across the facility.

Sediment Recirculation

The sediment recirculation system received critical mechanical upgrades, including new seals and bearings designed to prevent leaks during experiments.

These improvements reduce the risk of catastrophic failures, such as the entire channel draining overnight, and increase overall reliability during long experimental runs.

The sediment flux measurement system also got new hardware using a much more accessible and user-friendly system.

Tailgate

The tailgate now includes a radar sensor capable of measuring a wide range of water heights without requiring manual adjustment. Previously, a sonar-based sensor was used that required regular adjustments and calibration depending on water depth used in an experiment.

An additional sensor measures and controls the tailgate position, allowing operators to monitor and adjust conditions from a single location.

Tailrace

A new camera system allows researchers to monitor the sump safely from outside the tailrace.

The upgrade eliminates the need to physically crawl into the tailrace to inspect conditions, improving both safety and convenience.

These upgrades modernize one of SAFL’s most-used research facilities while preserving the experimental capabilities that have made the Main Channel central to research for decades. With automation and improved monitoring in place, researchers can now spend less time wrestling with infrastructure and more time focusing on their experiments.