In 2014, the city made strides in keeping excess phosphorous and nitrogen (which contribute to unhealthy river algae blooms) out of the Clark Fork River by planting 90,000 hybrid poplar trees irrigated with the facility's treated effluent. Instead of reaching the river, trace amounts of phosphorous and nitrogen in the treated effluent are absorbed by the trees as nutrition.
During the growing season of May through September, about 8,700 pounds of nitrogen and about 660 pounds of phosphorous are kept out of the Clark Fork River.
The site is located on Mullan Road, just west of Clark Fork Lane.
12 years after planting, the trees will be harvested for saw logs to be used for trim, wood, and furniture.