Day: June 10, 2025

Reviving a CSU legacy: 3D printing modernizes irrigation technology — #Colorado State University

Perry Cabot, left, and Manny DeLeon hold a 3D-printed Parshall flume that they created to make the water-measurement device more affordable and accessible. Photo credit: Colorado State University

Click the link to read the article on the Colorado State University website (Benjamin Randall):

June 9, 2025

At Colorado State University, innovation doesn’t always start in a state-of-the-art lab. It sometimes begins with a farmer in need, a researcher with a goal and a healthy dose of curiosity. That spirit drives work at the Colorado Water Center, where scientists and collaborators are rethinking how we manage and measure one of our most vital resources.

CSU Extension Professor Perry Cabot, who is jointly appointed through the Colorado Water Center and the Agricultural Experiment Station, is blending historic engineering with cutting-edge technology to make irrigation measurement more affordable and accessible. Cabot and a team of CSU researchers are harnessing the power of large-format 3D printing to revive and reimagine the Parshall flume – a century-old water measurement device first developed at CSU.

The project was made possible through funding from the Colorado Water Center’s grant program, which supports applied research projects that address urgent water issues across Colorado.

From legacy to low-cost innovation

The Parshall flume, invented by Ralph Parshall in 1921 at what was then called Colorado Agricultural College, remains one of the best methods for measuring water in open channels like irrigation ditches. Its distinctive shape slows and constricts the water as it flows through, making it possible to calculate the flow rate, or how much water is flowing through per second, by measuring the height of the water at a specific point in the flume. The flow rate is multiplied by the amount of time the water flows through the flume to calculate the amount of water. This information is essential for tracking and managing water used for irrigation, especially in regions where every drop counts.

“The genius of the flume is in the geometry,” Cabot said. “We can convert the height of the water in the flume into flow without needing fancy instruments, which is precisely why it has stood the test of time.”

Farmers can use flume data to schedule precise watering, reduce excess runoff and document their water use to meet regulatory requirements. By knowing the exact flow rate, a farmer can match irrigation timing and volume to crop needs more accurately. This minimizes the risk of overwatering, which wastes both water and energy, and reduces the risk of nutrient runoff. Over the course of a growing season, this kind of precision can lead to better harvests, lower costs and more sustainable use of limited water supplies.

However, traditional flumes are expensive, often ranging from hundreds to thousands of dollars, depending on size, and they are cumbersome to ship. For many farmers, researchers and conservation districts, the cost alone can be a barrier to access.

At left, a small 3D-printed Parshall flume inside the printer. At right, a larger version of a 3D-printed Parshall flume in action. Photo credit: Colorado State University

“We measure what we value, and we value water, but it’s a resource that’s increasingly difficult to put a clear, consistent price on,” said Cabot. “That lack of clarity makes it harder to justify costs associated with industrial tools like Parshall flumes.”

A common-sized Parshall flume (9 inches to 18 inches) made out of fiberglass can cost a few thousand dollars, while larger flumes made out of materials like aluminum, stainless steel or concrete can cost tens of thousands of dollars. The cost of the flume, plus installation and accessories, can make it a significant investment compared to the value of the water measured.

“Instead of buying an expensive, prefabricated flume, 3D printing allows us to create and sell Parshall flumes at a much more affordable rate,” Cabot said.

Manny DeLeon, a CSU researcher in the College of Agricultural Sciences and research technician on Cabot’s team, uses tools such as 3D printing to help develop low-cost technologies to make water measurement more accessible and efficient.

Using a durable, petroleum-based resin, Cabot and DeLeon have successfully printed the first large-scale Parshall flumes ever produced using additive manufacturing. Their 3D-printed version costs as little as 10%-20% of its traditional counterpart, with minimal compromise in durability or accuracy.

Printing the future of water management

Cabot sees this as a transformative step toward democratizing water measurement tools. His long-term vision is to decentralize flume manufacturing by equipping local conservation and river districts with the 3D printers needed to build and calibrate their own equipment.

“Imagine a farmer walking into their local conservation office, asking for a flume and walking out with one the next day,” Cabot explained. “This puts the tools of water management into the hands of the people using them.”

Rooted in service, driven by ingenuity

For Cabot, this project represents more than cost savings or tech adoption; it’s about service.

“My job is to help people,” he said. “Engineering, for me, is fun, but it’s also about solving problems that matter. That’s what engagement and extension are all about.”

That mindset has shaped every step of the process, from co-developing prototype irrigation tools with local farmers like Paul Kehmeier, to mentoring students involved in Cabot and DeLeon’s growing 3D printing lab at CSU’s Western Colorado Research Center, located about 7 miles southeast of Grand Junction.

Cabot said his work on the Western Slope is a great reminder for the future of research and innovation at CSU. “We don’t need to have the flashiest tools to build something transformative that can change the world. All it takes is a little ingenuity, a bit of resin and those willing to do the work.”

Learn more

To explore more about CSU’s legacy in water innovation and the Colorado Water Center’s work, visit the Colorado Water Center’s website.

Ralph Parshall squats next to the flume he designed at the Bellevue Hydrology Lab using water from the Cache la Poudre River. 1946. Photo Credit: Water Resource Archive, Colorado State University, via Legacy Water News.

The June 1, 2025 Water Supply Outlook Report is hot off the presses from NRCS

Click the link to access the report on the NRCS website and to read about your favorite basin of interest. Here’s an excerpt:

#Colorado’s #Snowpack Declines as Summer Precipitation Patterns Begin — NRCS

Ruby Horsethief Canyon. Photo credit: NRCS

Click the link to read the release on the NRCS website:

June 6, 2025

Snowmelt is nearly complete across Colorado. Most basins report early melt and below normal runoff forecasts. Early monsoonal precipitation has started and increased rainfall is expected to continue through the summer, particularly across southern regions. 

Colorado’s snowpack is nearing its seasonal end. Melt-out is occurring ahead of schedule across most of the state. Statewide snowpack is at 54 percent of normal. Snow water equivalent (SWE) statewide declines rapidly and most high elevation sites are now melted out, with only isolated locations primarily in northern basins retaining measurable snowpack. Statewide snowmelt is tracking 10 days earlier than median based on historical trends. The San Juan Mountains and Sangre de Cristo Range show a more pronounced signal. Many sites record snowmelt onset dates 20 days or more ahead of median. Southern sites already hampered by a meager accumulation season experienced accelerated melt due to persistent warm temperatures through May. Sites in the Front Range and near the divide have held onto snow slightly longer and are closer to normal melt-out timing.  

May brings a welcomed reprieve from dry patterns. Totals rank second highest for the water year to date (WYTD), behind only November. WYTD precipitation is at 86% of median statewide with May at 96% and outperforming traditionally stronger accumulation months like December, January and April. Despite lower climatological averages for May, precipitation was most favored in the San Juan Mountains, Sangre de Cristo Range and the Front Range. 

Early June storms extend the trend from May, delivering over 2 inches of precipitation at SNOTEL sites in the southwest between June 2 and June 5. Precipitation patterns shift toward higher humidity, more persistent cloud cover and frequent showers. These early June rain events align with the onset of the North American Monsoon, which often delivers afternoon storms and elevated atmospheric moisture, a vital source of summer water supply in southern Colorado.

Historically, 7% of annual precipitation falls during May, while June through September account for nearly 30% of annual accumulation in basins like the San Miguel-Dolores-Animas-San Juan (SMDASJ) and Upper Rio Grande (URG). A strong early start to the monsoon improves soil moisture, support reservoir levels and reduces wildfire risk as runoff tapers.  That said early monsoon activity also raises concerns about short-term risks. Flood watches have already issued for portions of the southwest. 

Observed streamflows reflect a compressed runoff season, particularly across the Western Slope. “Early snowmelt combined with limited snowpack has resulted in lower runoff forecasts, particularly in southern basins,” notes Nagam Bell, NRCS hydrologist. “Early monsoon activity could improve moisture conditions but consistent summer rainfall will be critical moving forward.” Southern and western basins run at approximately 50% of average flows for early June. Northeastern regions, benefitting from slightly better snow retention, track closer to seasonal norms but remain below median. 

Streamflow forecasts for the remainder of the runoff period reflect below normal runoff particularly west of the Continental Divide. Forecast departures from normal are concentrated across the Western Slope where the largest deficits are observed. At the Colorado River near Cameo the forecast volume is 391,000 acre-feet below normal. Upstream of the Colorado and Gunnison confluence the Gunnison River near Grand Junction forecasts a volume 351,000 acre-feet below normal. Statewide the average forecast percentile at the 50% exceedance probability is near the 22nd percentile based on 80 forecast points. The median forecast across the state is 67% for the 30-year median, with a majority of forecast points between 50% to 75% of median. Outlooks near major reservoirs including inflow into Pueblo Reservoir, Colorado River below Lake Granby and the Blue River below Dillon Reservoir are below median but generally near seasonal norms. By contrast, the Gunnison River inflow to Blue Mesa Reservoir is forecast at 64% of median and the Dolores River above and below McPhee are forecast near 60% of median. Forecasts point to continued low runoff volumes for rivers across the Western Slope, while flows in the Front Range and north central regions remain closer to median conditions. 

Statewide reservoir storage holds at 89% of median as of June 1. This marks a modest decrease from 93% a year ago. The Arkansas, URG, Gunnison, Colorado Headwaters and South Platte maintain near to above median storage ranging from 92% to 107% of median. The SMDASJ continues to trail at 74% of median with McPhee Reservoir at 66% capacity and 70% of median. These storage levels become increasingly important as snowmelt contributions diminish and summer water demand increases.

Colorado is shifting from snowmelt to summer moisture. While early runoff and below normal snowpack limit streamflow the recent precipitation and early monsoonal activity provide cautious optimism. NOAA’s seasonal outlooks forecast above normal precipitation for Colorado through the 6-10 day and monthly periods, with the southwest showing the strongest signal for wetter conditions. Temperatures are forecast to trend above normal statewide. 

* San Miguel-Dolores-Animas-San Juan River basin

* *For more detailed information about January mountain snowpack refer to the June 1st, 2025 Colorado Water Supply Outlook Report. For the most up to date information about Colorado snowpack and water supply related information, refer to the Colorado Snow Survey website.