The Wastewater Treatment Plant is a dual-powered,multi-cellular, aerated lagoon system with Submerged Fixed Film Media. The Cityis entrusted with the quality of water that our wastewater plant effluents intothe Snohomish River. The purposes of the Snohomish Wastewater TreatmentPlant are:
- Remove suspended solids and floatable material.
- Treat biodegradable organics.
- Reduce ammonia nitrogen.
- Eliminate pathogenic organisms from the wastewater.
The facilities mustmeet secondary effluent criteria and total maximum daily load (TMDL)-basedlimits specified in the National Pollutant Discharge Elimination System (NPDES)Waste Discharge Permit No. WA-002954-8. The NPDES permit also sets limitsfor influent flow and loading capacities. The WWTP has a permittedmaximum month influent flow of 2.80 million gallons per day (MGD) andpermitted maximum month influent load of 3,960 pounds per day (lb/day) for5-day carbonaceous biological oxygen demand (CBOD5) and 4,400 lb/dayfor total suspended solids (TSS). The WWTP is always looking at new andinnovative approaches to lowering costs while improving the quality of theeffluent leaving the plant.