Real Water Quality Benefits While Minimizing the Impact on Ratepayers by Reducing Compliance Cost

The City of Coeur d’Alene takes the stewardship of its local waterways very seriously. Their wastewater utility aims to protect human health and the environment through the efficient, cost-effective collection and treatment of its wastewater; dispose treated effluent into the Spokane River such that existing water quality is maintained, and its beneficial uses are not lessened; and produce and dispose of the highest quality biosolids in accordance with all applicable regulations. Because of this goal, nearly 40 years ago the city implemented a long-term, multifaceted approach to their wastewater treatment. 

Since 1980, the city has partnered with our team in all aspects of wastewater management and planning, including design for collections and treatment improvements, process analysis, master planning, capital program planning, financial analysis and rate studies. Staff from the city and HDR collaborated to develop wastewater solutions, including optimized nutrient control for phosphorus and ammonia removal for the protection of the Spokane River and the Rathdrum/Spokane Aquifer. 

Today, the city’s wastewater treatment plant meets one of the most stringent phosphorous discharge limits in the country, in addition to increasingly stringent ammonia-nitrogen removal and addressing carbonaceous biochemical oxygen demands effluent limits, all while developing treatment strategies to reduce the impact on ratepayers. Water quality conditions in the Spokane River and downstream in Long Lake (now Lake Spokane) drove the most recent wave of city planning and treatment plant improvements. 

We have worked with Coeur d’Alene for over 30 years at the Advanced Wastewater Treatment Facility on facility planning, Total Maximum Daily Load negotiations, National Pollutant Discharge Elimination System permit assistance, headworks and influent pumping station, and enhanced nitrification removal, digestion and dewatering. 

These are projects within the past 10 years: 

• 2018 Wastewater Facility Plan Update
• 2012 Wastewater Facility Planning Amendment
• 2017 Wastewater Rate Study UpdateWastewater Facility Phase 4A e-O&M Manual
• 2016 Wastewater Rate Study Update
• 2015 Toxics Management Plan
• Advanced Water Reclamation Facility Phase 5 Expansion
• Centrifuge Troubleshooting
• Dewatering System Evaluation and Centrifuge Procurement
• Digester-Clarifier Coatings
• Low Phosphorus Two-Year Demonstration Pilot Facility
• Permitting Support
• Phase 5C.1 Operation Support
• Phase 5C.1 Services During Construction
• Planning and Design of WWTP Phase 5C.1 Tertiary Filtration
• Tertiary Filtration Phase 2
• Tertiary Filtration Phase 2 - Services During Construction
• Wastewater Treatment Plant Integrated Fixed Film Activated Sludge System Retrofit