Post Falls Wastewater Treatment and Collection System Improvements
Post Falls, Idaho

The Post Falls Wastewater Treatment and Collection System project included planning, design, and construction management services for upgrades and expansion to the Post Falls collection, pumping and treatment systems. The treatment facility is an advanced nutrient removal system to meet strict nutrient limits on the Spokane River. The facility is located in Post Falls, Idaho.

The Issues: Rapid regional growth and very strict nutrient removal discharge requirements required careful system-wide Master Planning and numerous upgrades of the Post Falls Wastewater Treatment Plant.

How we addressed the issues: Working closely with the client and a long term program, J-U-B has provided design, construction management, startup, and ongoing assistance for all phases of Post Falls’ collection, pumping, and treatment systems since they were originally conceived. Post Falls operates an extended aeration oxidation ditch process with year-round biological phosphorus reduction and nitrification consistently performing to less than 0.5 mg/L. Aerobic solids stabilization, belt filter press biosolids dewatering, and ultraviolet disinfection processes are also utilized to meet its discharge requirements. Other recent improvements include the construction of the 2,100 gpm capacity submersible style lift station, standby generator and carbon filter odor control.

The Results: After a successful design and bid process, the plant has now expanded to 4.0 mgd with full biological nitrogen removal and concrete basin capacity up to 5.0 mgd.  Future challenges include balancing future growth with tightening budgets to meet <50ug/L TP, <4 mg/L CBOD and other stringent NPDES Permit limits due to the downstream TMDL process on the Spokane River. Water reclamation and reuse is also being planned as another key to Post Falls’ economic vitality through future upgrades and expansions.

The Benefits:

  • Strict TMDL and effluent NPDES Permit limits
  • Advanced biological nutrient reduction
  • Facility Planning for advanced tertiary treatment
  • Long-term program management to manage financial impacts and system sustainability
  • Improvements, expansion and optimization of the Water Reclamation Facility
  • Improvements to the City’s collection system, including lift stations and new force main

Awards and Recognition:

Third Place 2012 ACEC Engineering Excellence Awards – Water and Stormwater Category