What We Do

The wastewater treatment process is all about one important thing: cleaning dirty water. Check out the video below for a creative look at what happens after dirty water reaches a treatment plant.

Pretty good video, right? Although complex, the wastewater treatment process can be broken down into seven important parts:

Step 1: Screening

• Things that shouldn't go down the drain at home or the drain in streets are filtered out.
• This includes items like rags, baby wipes, disposable wipes, paper towels, medications, wood fragments, plastic, and other debris.
• These items are collected for transport to the local landfill.
• Once the large items are removed, the wastewater flows to the next step.
  
  

Step 2: Grit Removal

• Wastewater enters a grit chamber where a large propeller separates heavy organic materials like sand, gravel, clay, and coffee grounds from the wastewater.
• The spinning propeller causes the heavy organic material to be forced down the grit chamber's walls where it is collected.
  
  

Step 3: Primary Settling

• Water flows into large clarifiers where the remaining organic material is given more time to settle out.
• Heavier material sinks to the bottom of these tanks, while lighter materials, like grease and fats, float to the top.
• Large arms, called skimmers, move slowly around the top of the settling tank and push material like grease into a collection trough.
• Heavier material settles at the bottom of the tank and forms sludge.
• The sludge is moved into a collection tank under the clarifier by submerged skimmers.
• Floating debris is captured and removed by large arms that slowly spin around the top of the clarifier.
• Chemicals added to remove phosphorus.
  
  

Step 4: Aeration

• Wastewater moves from the clarifying tanks into an Aeration chamber.
• At this point, the wastewater is beginning to look much clearer and cleaner, but it still isn't safe to return to the environment.
• Special bacteria and micro-organisms, sometimes called activated sludge, are mixed into the wastewater.
• These special bacteria consume biodegradable material as food, but they need oxygen to survive.
• Special baffles in the aeration tank introduce this oxygen, allowing the micro-organisms to further break down or clean the wastewater.
• Over time, these bacteria clump together and form heavy clusters called floc.
  
  

Step 5: Secondary Settling

• The wastewater and floc mixture is now ready for further separation and move into a secondary settling tank, similar to the clarifier.
• The heavy floc slowly settles at the bottom of this tank, allowing much cleaner water to be slowly removed from the surface.
  
  

Step 6: Filtration

• At this point, the wastewater looks like regular water, but it still isn't ready to be returned safely to the environment.
• The nearly-clean water now passes through a filtration system that pulls out any remaining solids that aren't visible to the human eye.
  
  

Step 7: Disinfection

• Once the nearly-clean water finishes the filtration process, it proceeds to final disinfection.
• During final disinfection, the water passes slowly through ultraviolet light, where any remaining harmful bacteria are removed.

And that’s it! The now clean and safe water is returned to local streams and rivers to participate once again in the Water Cycle.

The WPC team is responsible for maintaining, repairing, and replacing more than 800 miles of wastewater pipes. Those pipes are what move dirty water away from homes and businesses to five treatment plants that clean more than 8 billion gallons of water a year before returning it safely to the environment.

Repairing sewer pipes across Wyandotte County is a priority, as the reliability of our existing infrastructure impacts public health, public safety, property, and local water quality. WPC is always working on:

• Minor sewer repairs.
• Major sewer replacements.
• Rebuilding catch basins and manholes.
• Repairing line breaks during emergencies.
  
  

Excellent asset management and a long-term outlook help ensure the wastewater system remains in good working order. WPC's aggressive maintenance program includes:

• Developing a system-wide cleaning schedule for the sewer lines.
• Televising and inspecting the condition of 800 miles of sewer lines.
• Prioritizing the most problematic lines in the system.
  
  

Daily and periodic maintenance and inspections help:

• Reduce sewer overflows.
• Reduce the occurrence of basement backups.
• Identify areas with high volumes of grease and roots.
• Identify potential repairs before they become costly emergency repairs.

Our stormwater is managed through a complex system of storm drains, pipes, culverts, drainage ditches, and even streams. Every time it rains, stormwater runs off into either a combined sewer system or a separate storm system. If it enters a combined sewer system, it mixes with wastewater and is sent to a nearby treatment plant. However, when it enters the separate storm system, it is sent directly to our waterways.

When stormwater flows across our yards and streets, it picks up pollutants. These pollutants include trash, debris, pesticides, fertilizers, animal waste, oil and grease, and other contaminants. These pollutants ultimately end up in our waterways and can impact our water quality. Keeping our waterways clean is critical for life – our water is used as drinking water for residents and businesses and serves important industrial, agricultural, and recreational purposes.

Learn more about Stormwater Runoff Management