Infrastructure - Waste Water Disposal

What is wastewater?

“Wastewater is all the ‘used’ water that flows out of your kitchen sink, dishwasher, toilet, bathtub, shower, washing machine, or any drain in your home or business. This water can carry with it lots of different things depending on what you’ve used it for, like shampoo from the shower, laundry soap from washing your clothes, tiny bits of food from washing your dishes, and of course, the stuff that goes down the toilet.” 

Source: Portland-gov – About the Wastewater Treatment Process

How much waste water does Bridlemile generate per day?

Bridlemile generates ~554,000 gallons of wastewater per day.

And how was the above estimate made?

The average person in the United States generates almost 100 gallons of wastewater per day =- flushing the toilet, bathing and washing dishes. (Source: PBS). Bridlemile has 5,537 residents. (Source: Portland.gov – Bridlemile neighborhood profile from 2020 US Census data)

So, 100 gallons/day * 5,537 Bridlemile residents = 5,537,000 = ~554,000 gallons of wastewater per day.

Of this amount:

24% covers toilet flushes (about 5 per day)

20% covers taking showers (at 8 minutes each)

19% covers bath and kitchen sink faucet use (23 minutes per day)

17% covers clothes washing (300 loads per year)

Source: Portland.gov – Saving water in your home

When did Portland and Bridlemile start treating wastewater?

“Prior to the (Columbia Wastewater Treatment) plant opening in 1952, sewage, agricultural, and industrial waste went directly into the Willamette River and Columbia Slough—a practice that today would be unthinkable.”

Source: Portland.gov – Columbia Boulevard Wastewater Treatment Plant

But, apparently, even after that plant opened in 1952, at least some Bridlemile residents still had trouble disposing of their wastewater.

A November 25, 1956 Oregonian article reported on a proposed sewer plan for the entire west slope of the West Hills, including the recently annexed Bridlemile area. It took seven more years, until 1963, for the City Council to approve a resolution calling for construction of a sewer system to help un-connected areas of Bridlemile. The city claimed “the technical difficulties, caused by terrain that slopes four ways, and the fact that part of the area is served by the city and part by the county has caused delays in designing and letting a contract for a practical system at a realistic cost.” (Oregonian, March 29, 1963)

Where does Bridlemile waste water go?

Waste water goes out from each residence’s main sewer line to the public main sewer line.

Sewer manholes provide a location for maintenance workers to inspect and, if needed, clean the sewer system. Typically, they are located at junction points in the sewer system.

Waste water flows through a network of larger-and-larger sewer-system pipes and pump stations. Portland has more than 2,500 miles of pipes, 100 pump stations, and two treatment plants. They process an average of 70 million gallons of wastewater daily, and up to 450 million gallons on rainy days. Source: Portland.gov – About Our Sewer and Stormwater System

Eventually, the waste water reaches the Columbia Boulevard Waste Water Treatment Plant. This facility handles Portland’s waste water, both sewage and storm runoff water. It is located in North Portland at 5001 N Columbia Boulevard. This plant cleans the water and recycles it into the Columbia River.

How does Bridlemile’s (and Portland’s) waste water get cleaned?

For those interested in how waste water gets cleaned after it leaves Bridlemile,

Either read a Portland.gov description titled: “About the Wastewater Treatment Process”

Or watch a Portland Bureau of Environmental Services video: After the Flush.

What About Storm Water?

In addition to the waste-sewer water system, Portland has a “storm water runoff” system that collects water from Portland’s average yearly 37 inches of rainfall. Portland has over 55,000 storm drains, of which Bridlemile has about 480.

To help you find Bridlemile storm drains, click: https://projects.oregonlive.com/weather/flooding/storm-drains

For more information: Portland.gov – How We Manage Stormwater