The City of Boise and Brown and Caldwell received the national honor in the American Council of Engineering Companies (ACEC) 51^st Engineering Excellence Awards competition.

Known industry-wide as engineering’s “Academy Awards”— the competition concludes with a gala celebrating U.S. engineering firms for projects demonstrating exceptional innovation, complexity, achievement and value. Thirty-six projects were honored before an audience of industry professionals, government officials and dignitaries at the April 17 event in Washington, D.C.

The prestigious Grand Award, one of only 16 given annually, was presented to the City of Boise and Brown and Caldwell for the Dixie Drain Phosphorus Removal Facility. Grand Awards recognize engineering accomplishments that contribute to the advancement of engineering and enhances the economic and social welfare of the public. This year’s competition yielded hundreds of entries as a distinguished panel of judges selected the nation’s best projects to receive Grand Awards.

The Dixie Drain Phosphorus Removal Facility treats 130 million gallons of water daily.

To reduce the impact of excess phosphorous entering the Boise River, regulations required a 98 percent phosphorus discharge reduction from Boise’s water renewal facilities. As the city makes improvements at its facilities to remove 93 percent of the phosphorus, upgrades to eliminate the remaining five percent would require costly modifications. Subsequently, the city implemented a pioneering pollutant offset approach via the Dixie Drain Phosphorus Removal Facility project.

Located 34 miles downstream from Boise’s primary water renewal facilities, the Dixie Drain Phosphorus Removal Facility collects ground and surface water from agricultural operations in the lower Boise River watershed, removing 140 pounds of phosphorus per day (10 tons annually). For every pound uncollected at a Boise upstream facility, 1.5 pounds are removed downstream at the Dixie Drain Phosphorus Removal Facility, a more cost-effective solution with significantly greater environmental benefits to the Boise and Snake rivers. This non-point phosphorus removal offset is written directly into the city’s National Pollutant Discharge Elimination System permit.

The city hired Brown and Caldwell, a leading environmental engineering and construction firm, to conceptualize, pilot, and design the $21 million facility, which this year received two regional ACEC awards—ACEC-Idaho’s Grand Concept Award and first place in their water and stormwater category.

“We’re proud to see national recognition for the combined efforts of the City of Boise, Brown and Caldwell, local contractors, and the community,” said Brown and Caldwell CEO Rich D’Amato. “Our commitment and passion to solving environmental challenges for clients while enhancing the communities we touch is abundantly evident at the Dixie Drain Phosphorus Removal Facility project. Not only does the project enable Boise to meet federal regulations, it also provides long-term environmental benefits.”

According to the city’s Public Works Director Steve Burgos, this groundbreaking yet commonsense approach is a model for regions facing nutrient removal challenges and budget constraints.

“This innovative solution eliminated the need to implement more capital-intensive modifications and at the same time remove 50 percent more phosphorus that would have been otherwise untouched,” Burgos said. “The Dixie Drain Phosphorus Removal Facility project is setting a national precedent for addressing water quality issues more effectively and affordably.”

Burgos attributes the project’s success to strong collaboration among numerous stakeholders including the city, Brown and Caldwell, the U.S. Environmental Protection Agency, Idaho Department of Environmental Quality, Idaho Conservation League, and elected officials. Additionally, he commended Brown and Caldwell for its steadfast partnership on the project.

“From initial concept all the way through pilot testing, permitting, final design, and construction, Brown and Caldwell was with us every step of the way to make this groundbreaking project a reality,” Burgos said.