City crews responded to a sewage overflow near SW Sunset Blvd and SW Richardson St this morning, identifying the cause as ongoing heavy rains. The release was first observed around 9:50 a.m. and stopped around 12:20 p.m.

Environmental Services estimates that about 3,000 gallons overflowed from a property cleanout on SW Sunset Blvd, ran down the street, and into a stormwater inlet that leads to a small unnamed creek that connects to Fanno Creek.

Environmental Services advises the public to avoid contact with Fanno Creek downstream of SW Dosch Road and Beaverton-Hillsdale Hwy for at least 48 hours and heed warning signs posted near SW Sunset Blvd and SW Richardson St.

While the cause of the sewage overflow was heavy rains, Environmental Services reminds the public that most sewage overflows are preventable. The most common causes are grease, tree roots, wet wipes, and other debris that clog and block pipes.

Environmental Services advises the public to follow these tips to prevent clogs in homes and businesses and to prevent sewage releases:

• Never pour grease down drains: Collect grease, oil, and fat in a can and then into the garbage. Grease that is liquid when poured down drains will become solid once in pipes.
• Only flush human waste and toilet paper (wet wipes are NOT flushable).
• Don’t put anything down storm drains, which are intended for rainfall only.

If you experience or see a sewer overflow, contact the City of Portland’s 24/7 hotline: 503-823-1700.

About Environmental Services
Environmental Services - the City of Portland’s sewer and stormwater utility - protects public health and environment by collecting and recovering resources from the city’s wastewater, managing stormwater, and restoring and protecting Portland’s rivers, streams, and watersheds. Portland.gov/bes

Big Pipe Tracker shows 100% full as of 7:15 a.m.

Heavy rains led the Big Pipe system to reach capacity around 7 a.m., leading to a combination of stormwater and sewage overflowing to the Willamette River from multiple outfalls. 

The combined sewer overflow (CSO) affects the stretch of the river downstream of Sellwood Park. The overflow is ongoing at this time.

During an overflow and for 48 hours after an overflow stops, the public is advised to avoid contact with the river because of increased bacteria in the water. The river’s water quality is safe for recreation during all other times.

A CSO is about 80 percent stormwater and 20 percent sewage. CSOs are rare and can occur during periods of heavy rain or snowfall. 

The public can follow the duration of this overflow by viewing the Big Pipe Tracker online.

Since completing the Big Pipe project in 2011, the 20-year $1.4 billion program to reduce overflows, the number of CSOs have dropped by 94 percent to the Willamette River and 99 percent to the Columbia Slough. Before the project, incidents occurred to the Willamette River an average of 50 times a year, with some lasting days. Today, overflows occur an average of four times per winter season and once every three summers. 

This is the fourth CSO of the year.  As of yesterday at noon, the Big Pipe system had captured and prevented about 300 million gallons of diluted sewage from reaching the river since this week’s series of storms began. There is no immediate estimate for today’s overflow. 

The Big Pipe system refers to a series of improvements, from disconnecting downspouts on homes to allow rainwater to be absorbed naturally in the ground to the construction of big pipes on both sides of the river and along the slough to store and convey large quantities of flows to the City’s main wastewater treatment plant in North Portland. Visit About CSOs to find out more.

About Environmental Services

Environmental Services - the City of Portland’s sewer and stormwater utility - protects public health and environment by collecting and recovering resources from the city’s wastewater, managing stormwater, and restoring and protecting Portland’s rivers, streams, and watersheds. portland.gov/bes 

Big Pipe Tracker showing 72 hours of data

With a series of atmospheric rivers coursing through the Portland area this week, the City of Portland Bureau of Environmental Services data show that the Big Pipe system has so far prevented multiple combined sewer overflows (CSOs) to the Willamette River.  

The Big Pipe Tracker has shown four spikes so far during this storm system. Each spike represents sewage mixed with rain that the Big Pipe system intercepted and prevented from overflowing to the river. BES operators instead store the mixture in two giant pipes on either side of the river and then direct that flow to the City’s main wastewater treatment plant in North Portland.  

BES estimates that since Sunday, the Big Pipe system has prevented more than 300 million gallons of diluted sewage from reaching the river. 

The public is encouraged to follow the Big Pipe Tracker for the remainder of the storm, and during future storms. As long as the gauge is under 100%, the river continues to be sewage-free. If an overflow occurs, the gauge will reach 100% and BES will issue a news advisory shortly after. 

 A CSO is about 80% stormwater or rain, and 20% sewage. 

Before the Big Pipe system was completed in 2011, overflows occurred almost every time it rained, an average of 50 times a year, with some overflows lasting days. Today, CSOs are rare. The number of CSOs has dropped by 94 percent to the Willamette River and 99 percent to the Columbia Slough. 

—-

About Environmental Services

Environmental Services - the City of Portland’s sewer and stormwater utility - protects public health and environment by collecting and recovering resources from the city’s wastewater, managing stormwater, and restoring and protecting Portland’s rivers, streams, and watersheds. www.portland.gov/bes