Idaho Rivers United released its first Boise River Report Card on May 22, 2026, giving the waterway a B to B-minus grade based on 103 water quality tests conducted by volunteers last year. The report card gave the Boise River high marks for water clarity, pH level and average temperature.
The tests were performed at three locations along the Boise River: Barber Park, the Parkcenter Boat Ramp, and the Americana Bridge. Idaho Rivers United plans to continue water testing and issue updated reports each year, with this first year intended as a baseline for annual comparisons, according to Communications Director Dave Womack.
What the Report Card Found
Idaho Rivers United officials said the Boise River is healthier in every respect compared to previous decades, when the river was polluted and used as a dumping site, before the Clean Water Act was passed in 1972.
The report noted the Boise River is continuously cleaned up by volunteers, supports a variety of aquatic life and offers tremendous recreational opportunities for the public. Womack said the river remains safe for recreation and meets federal standards for human contact under Clean Water Act requirements, allowing people to swim, fish and touch the water.
The report card measured eight indicators: average river temperature, pH level, dissolved oxygen levels, turbidity, biochemical dissolved oxygen levels, prevalence of nitrates and phosphates, total coliform bacteria, and trash removal.
The Boise River got top marks for turbidity, pH levels, average temperature, and trash removed from the waterway. Water temperatures ranged from 6°C to 20°C, typical for the Boise River and supporting most cold-water species, though warmer days later in the season pushed temperatures toward 20°C.
The ideal pH range for healthy freshwater streams is between 6.0 and 8.0, and a pH near neutral supports a wide variety of fish and other aquatic organisms, meaning the Boise River is nearly perfect in this regard.
Officials did find a few areas of concern and some factors that they said merit additional testing and monitoring.
Officials said the amount of oxygen in the water for aquatic species may be less than ideal. Due to limitations of the testing kits, not enough precision was possible to provide an accurate representation of dissolved oxygen levels, and the organization believes the 4.27 mg/L result may be inaccurate. After excluding readings of 0 mg/L as nearly impossible for rivers, the revised average dissolved oxygen concentration of 4.5 mg/L still falls near the lower limit of fish tolerance and is unsuitable for prolonged exposure.
Officials also said coliform is present, but they could not identify the type or concentration of bacteria. Around 75% of test results were positive for coliform bacteria, but the tests employed simply return a result of positive or negative with no indication of concentration level. Further testing is necessary to identify the kind of bacteria and quantify the number of colonies found.
The report card noted that conditions for salmonid spawning and coldwater aquatic life are suboptimal due to temperatures, low flows and habitat alteration. Womack noted that warmer water temperatures can make it difficult for species such as salmon and trout to reproduce successfully, with some factors including the overall temperature getting a little too warm for them to feel comfortable spawning in the river.
Phosphate levels tested high, however the test kits used did not have the ability to read small concentrations or provide precise measurements, and the results have been deemed inconclusive due to the testing equipment not producing reliable results.
The report also highlighted concerns about elevated nitrogen concentrations, which can contribute to algae growth.
Volunteer-Driven Effort
In conjunction with the release of the Boise River Report Card, Idaho Rivers United officials highlighted their Boise River Stewardship volunteer program. Through the Boise River Stewardship program, volunteers donated 486 hours of volunteer time, conducted 15 Boise River cleanups and removed 971 pounds of trash from the river and conducted 103 water quality samples along the river.
Overall, Idaho Rivers United reported removing 3,850 pounds of trash from the river last year. During the organization's annual spring cleanup in April, 233 volunteers removed more than 1,400 pounds of trash from areas along the river.
Boise resident Madeleine Shapiro has been volunteering as a Boise River Steward for four years, since she heard about Idaho Rivers United's volunteer programs while attending a local beer festival, and said it is a perfect volunteer opportunity because she is able to volunteer on weekend mornings and help clean up the same sections of the Boise River that she enjoys fly fishing in.
Womack said rapid growth in the region has brought an increase in trash along the Greenbelt and river corridor, noting it's saddening and makes people want to immediately start picking up anything around.
Why It Matters for Idaho Business
The Boise River is a major economic asset for the Treasure Valley. The waterway provides drinking water, agricultural irrigation, and recreation that draws residents and tourists. Water quality directly affects property values along the Greenbelt, outdoor recreation businesses, and the region's quality-of-life appeal to employers and workers.
Womack said the report is intended to be an ongoing resource to provide information to decision makers, to the public and to anyone who will be impacted by the water quality.
For Womack, the river is central to life in the Treasure Valley, describing it as the artery that runs through the region. Womack said access to the river is one of the reasons he enjoys living in Boise, noting he is able to spend time floating the river several times a summer and bikes along it to work every single day.
Idaho Rivers United is a Boise-based nonprofit organization and the only statewide river conservation organization in Idaho. The group works to protect and restore Idaho's rivers and fisheries, with a focus on wild salmon and steelhead, water policy, and mining reform.
Womack said the organization hopes to continue collecting data annually to help guide future conservation efforts. "As good as we are, we can do better," he said. "Our resources are finite, and if we don't take care of them, we're going to lose them."
The report card is available on the Idaho Rivers United website. Information about volunteering for river cleanups is also available on the organization's site.