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Wastewater Infrastructure

Wastewater Infrastructure

King County Wastewater Treatment Division (WTD) Landing Page

King County WTD collects and treats approximately 175 million gallons of wastewater per day from about 1.7 million people. Source control efforts help prevent pollutants from entering the wastewater system. Check out their main webpage and be sure to navigate to whichever of the 12 topic tiles interest you! Poke around! 


King County WTD Sustainability Infographic

This two-page fast-facts infographic highlights the successes of King County’s WTD as a clean water utility dedicated to protecting public health and enhancing the environment. View impact data on sustainability indicators including number of people educated, amount of water recycled, and total energy saved. 


American Society of Engineers Wastewater Report Card

A 2017 “Infrastructure Report Card” infographic featuring wastewater statistics. See this page for large-scale facts about the current status and needs of U.S. wastewater infrastructure.

WTD Project Case Study Videos: What’s going on in King County? 


Wastewater Treatment Plant Tour Videos:

How does water from my toilet become clean? Engineering!


VIDEO - Understanding the Clean Water Plan Process (3:47)

How can we impact the Clean Water Plan, and how does it impact us? 


VIDEO - Wastewater Engineers Education Video Series 

These 4 mid-length videos, targeted towards an elementary-aged audience, introduce fundamental concepts in wastewater. Narrators are interesting and speak directly to a student audience, often encouraging viewers to participate and actively learn with their own materials 


Racial Equity Toolkit for Water Utilities 

This is a breakthrough document developed by the US Water Alliance to enable water utilities of all sizes to improve their racial equity practices and outcomes both internally and externally.  For too long, the water utility sector has been operating within systems in which race is a predictor of water access, affordability, quality, reliability, and resilience in the face of our increasingly disruptive and volatile climate. The tool kit is a guide for developing solutions to correct this situation.

Resource Recovery

Resource Recovery

Meet the Peecyclers. Their Idea to Help Farmers Is No. 1.

Is human urine just what plants need amid a fertilizer shortage? Human urine is, in fact, full of the same nutrients that plants need to flourish — even more than poop!

King County Loop Biosolids

Poop as a fertilizer?! Of course! Loop is King County’s biosolids product. It is an endlessly renewable resource. For over 40 years, it has recycled the nutrients in our food back to the land the same way nature does. Learn more on the main page of their website.

Biosolids Strategic Plan

Part of WTD’s mission is “recycling valuable resources” from wastewater treatment, including recycled water, biosolids, and energy produced from biogas. See how the county specifically plans to deal with biosolids in this comprehensive 17-page planning document. 


Cool pages:

  • Page 7-8 - Strategic Plan Overview Table with 3 main goals

  • Page 14 - Goals Rationale, summarizing strategy behind key goals


Creating Resources from Wastewater

Learn about Loop®, King County’s biosolids product, through these 4 short videos. Loop® is a fertilizer alternative produced by cleaning, recycling, and transforming King County's wastewater into biosolids


King County Recycled Water

King County’s recycled water is created by advanced wastewater treatment that works to mimic nature’s processes of filtering and cleaning used water. Be sure to check out the county’s Water Uses page to learn about specific areas where recycled water is most crucial. Curious about locations of existing recycled water systems? Check out King County Recycled Water Maps

Sewer Heat Recovery

WTD is the first in Washington state and one of the first wastewater utilities in the nation to offer Sewer Heat Recovery (SHR). Private commercial property owners and developers can recover heat energy from our sewer pipes for heating or cooling their buildings. Check out a cool graphic on how it works here!

Combined Sewer Overflows

Combined Sewer Overflows

King County Combined Sewer Overflow Map

In certain neighborhoods in Seattle, sewage and stormwater are carried by the same pipes in a combined sewer system. When heavy rains fill the pipes, CSOs release untreated sewage and stormwater into rivers, lakes, or Puget Sound.


2020 CSO Snapshot

Take a peek into how the city dealt with wastewater overflows in 2020 through this cool infographic. Be sure to look at the map labeling CSO outfall locations! 

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