Deer Lodge Wastewater Treatment Plant

Site Constraints and Funding Shortage

Deer Lodge has some significant landmarks not found in a typical small town. It is home to the Montana State Prison and The Grant-Kohrs Ranch. Their wastewater treatment plant site was donated to the city in the late 1950s by the last owner of the Grant-Kohrs Ranch prior to turning the ranch over to the U.S. Department of the Interior. By working collaboratively with both of these community partners, a long-term and cost-effective solution was found for the city’s wastewater treatment facility that contributes to the continued vitality of Deer Lodge.

Alternative sites for the WWTP were considered to try and lower the number of site constraints but ultimately proved infeasible. As a result, Morrison-Maierle and the city were faced with a long approach; building on city land that was landlocked by the Clark Fork River, a national historic site, the BNSF Railway, and private property. In addition, a sensitive bald eagle nesting site was located less than ¼-mile from the site, triggering compliance with the Bald and Golden Eagle Protection Act. Building the project required obtaining funding from numerous state and federal agencies to create an affordable project and construction at their existing site required meeting numerous complex state and federal cultural, historic preservation, and environmental requirements, and executing a new railway crossing and a land exchange with the National Park Service.

Space was also an issue with this project as it sits within a 100-year floodplain. The former facility included a four-cell aerated lagoon and had limited space for the new facility. In order to use the existing site, lagoon Cell 4 was filled. Since the WWTP is on the 100-year floodplain of the Clark Fork River, a Conditional Letter of Map Revision for Fill had to be approved by FEMA. Morrison-Maierle prepared a hydraulic model of the river to show the floodplain’s boundaries with the Cell 4 fill in place, submitted it to FEMA, and responded to their questions upon review.

In addition to the site constraints, after five years of violations of state discharge limits, Montana’s Department of Environmental Quality (DEQ) issued a mandatory compliance order for the community to upgrade its wastewater treatment facility within two years. The preliminary engineering report estimated that the project would cost more than $17 million, the equivalent of $75 per month for every household on top of their current sewer bill. Grant funding was the only way to make the project affordable to the small community of 3,200 residents. Morrison-Maierle worked with the city to seek funding from seven different sources including state and federal agencies.

The city, with assistance from Morrison-Maierle, completed negotiations with DEQ to extend the compliance schedule to allow time for the city to obtain grant and loan funding for the project. The final funding package included approximately $6.625 million in grant dollars reducing the needed sewer rate increase by 65 percent.

Working Next to a Historic Site

An additional challenge for the team was the fact that the trunk main flowed entirely through the Grant-Kohrs Ranch, requiring the need to minimize visual and aesthetic impacts from construction. The project was accomplished by using trenchless construction and limiting construction activities to the winter months when the ground was frozen. The project successfully eliminated the groundwater infiltration without impact to the national historic site and reduced the summertime average flows by over 60 percent.

Construction of the new wastewater treatment plant involved numerous new concrete tanks and buildings which were determined to have potential cultural and historic impacts on the Grant-Kohrs Ranch. Morrison-Maierle worked with the National Park Service to develop building profiles and finishes that blended with the landscape to minimize the impacts to the view shed of the ranch.

The access road, which traversed private property, the BNSF railroad tracks, and the Grant-Kohrs Ranch, also had to be widened. To accomplish this, three agreements were obtained: an easement was negotiated with the private landowner followed by a land exchange and interim Special Use Permit negotiated with the National Park Service that required an extensive title search, preparation of an Environmental Assessment, and approval from Department of Interior Region 8 headquarters. This would not have been possible without the full support of the Grant-Kohrs Ranch superintendent. Finally, a new railroad crossing permit was needed from Burlington Northern.

To comply with Section 106 of the National Historic Preservation Act, the team prepared an Environmental Assessment and assisted the city in negotiating an MOU with the Montana State Historic Preservation Office, the National Park Service, and the U.S. Department of Agriculture. The MOU required Morrison-Maierle’s design to address potential visual impairments to the ranch that included minimizing the exterior lighting, use of colors and textures on buildings to blend with the natural landscape, use of numerous smaller buildings to mimic outbuildings of the ranch and minimizing building and tank heights.

Sustainability and Habitat Protection

In terms of sustainability, one of the byproducts of the new wastewater treatment process is biosolids, which must be disposed of by either landfilling, composting, or land application. However, the nearest composting facility to the WWTP is more than 40 miles away and the county’s landfill was nearing capacity and therefore reluctant to accept the material. Morrison-Maierle worked with the Montana State Prison to develop a Memorandum of Agreement with the city to deliver the biosolids for land application on the agricultural fields at the prison’s nearby ranch. This solution represents a significant cost saving for the city since the ranch is only six miles away and there are no tipping fees like those at the landfill. Furthermore, this solution also benefits the prison as it provides a free, agronomic benefit from the nutrients in the biosolids.

During the preliminary design phase, a bald eagle nest was identified within ¼-mile of the WWTP. The planned construction activities triggered compliance with the U.S. Bald and Golden Eagle Protection Act.

Morrison-Maierle assisted the city in obtaining an Eagle Take Permit from the U.S. Fish and Wildlife Service. This process involved documentation of existing breeding and nesting activities starting one year prior to construction and for three years during the permitted period. The permit application identified certain mitigation measures taken during construction activities, including starting construction after eagles had fledged the nest and then resuming and finishing construction prior to breeding activities the next year.

This schedule limited the impacts to one breeding season. As a result, three eaglets successfully fledged in that time period.