01 — Current research
From snowball fighting to water research.
Snowball League is now being reconsidered as part of a larger research question: could snow produced for recreation also participate in a freeze-filtration process?
02 — How it could work
01
Source water
Water selected for study
02
Freezing
Ice forms as impurities concentrate
03
Ice / snow
Ice separated from the remaining water
04
Recreational use
Snow used for play
05
Melting
Snow returns to water
06
Recovered water
Under investigation
As water freezes, the ice phase can exclude some dissolved impurities. Research is investigating whether this separation process could be connected with recreational snow production.
This is a research hypothesis
Snowball League does not currently treat water, and no technical performance has been demonstrated. Technical feasibility, water quality, energy requirements, economics and appropriate water sources are all still being investigated.
03 — The bigger system
A future course could potentially connect five things at once.
01
Water
02
Snow production
03
Recreation
04
Scoring
05
Water recovery
Described as a potential future system, not as a built or proven facility.
04 — The science
The science behind freeze separation.
Freeze separation—also called freeze crystallization or freeze concentration—uses controlled freezing to separate relatively cleaner ice from contaminated water. As ice grows, many dissolved contaminants remain in the unfrozen liquid, becoming more concentrated. The ice must then be physically separated from that liquid.
Snowball League is investigating whether freeze separation could connect water treatment with recreational snow production. Published studies support the process for specific wastewater streams, but its performance with agricultural drainage water and its suitability for recreational use still require testing.
01
Starting water
Water containing dissolved contaminants.
02
Controlled freezing
Ice grows while many contaminants remain in the liquid. Some stay trapped in the ice.
03
Physical separation
Ice is removed from the contaminant-rich liquid.
04
Testing
Recovered ice or meltwater is analyzed to determine its quality and whether more treatment is needed.
Concentrated liquid · Requires further treatment, recovery, or appropriate disposal.
05 — Published research
Lorain et al. — Dissolved pollutants
Lorain, O., Thiebaud, P., Badorc, E., & Aurelle, Y. (2001). Potential of freezing in wastewater treatment: soluble pollutant applications. Water Research, 35(2), 541–547.
Investigates how controlled freezing separates water from dissolved pollutants by concentrating those pollutants in the remaining liquid.
Read Study →John et al. — Municipal wastewater and landfill leachate
John, M., Häkkinen, A., & Louhi-Kultanen, M. (2020). Purification efficiency of natural freeze crystallization for urban wastewaters. Cold Regions Science and Technology, 170, 102953.
Tested municipal wastewater and landfill leachate under simulated winter conditions. At low ice-growth rates, municipal wastewater achieved 95% to nearly 100% purification for measured indicators such as chemical oxygen demand. These results do not mean that every contaminant was removed.
Read Study →Muga et al. — Nitrate and phosphate
Muga, E. C., Komakech, H. C., & Jande, Y. A.-C. (2023). Establishing the optimal condition for nutrient recovery from domestic wastewater using the freeze concentration method. Water Practice & Technology, 18(8), 1853–1862.
Studied freeze concentration of real domestic wastewater to recover nitrate-nitrogen and phosphate in the unfrozen liquid. Phosphate concentration increased more strongly than nitrate, showing that different contaminants respond differently.
Read Study →More et al. — Demonstration equipment
More, K. S., Maree, J. P., & Mahlangu, M. (2025). Cost-Effective Leachate Treatment and Resource Recovery in Hazardous Waste Landfills through Pipe Freeze Crystallization. Environmental Processes, 12, Article 15.
Demonstrated a freeze-crystallization system using actual landfill leachate. The system recovered ice and salts, and the recovered ice contained substantially fewer dissolved solids than the starting water. Residual impurities remained.
Read Study →
Click to enlarge
Click to enlarge
Source: More, Maree, and Mahlangu (2025), Figures 3 and 2, respectively. Reproduced without modification under CC BY 4.0.
06 — The current study
Take the survey.
Part of the research is understanding whether people are interested in the recreational concept, and whether the environmental purpose changes that interest.
Take the 2–3 minute survey