Cryptosporidium

We’re Keeping Drinking Water Safe for You & Your Family

In January and February 2017, the Portland Water Bureau detected Cryptosporidium, a microscopic parasite that can cause a gastrointestinal illness, in several routine water samples taken from the Bull Run Watershed water supply.

In Washington County, Oregon, the Joint Water Commission (JWC) Water Treatment Plant is the primary drinking water supplier. Four agencies share ownership in the JWC – Cities of Hillsboro, Forest Grove, and Beaverton, and the Tualatin Valley Water District (TVWD).

The JWC also wholesales water to the City of North Plains.  The City of Cornelius receives JWC water through the City of Hillsboro. The City of Gaston and LA Water Cooperative both receive water from JWC and the Cherry Grove Slow Sands Water Treatment Plant.

Below is information on Cryptosporidium and how the JWC Water Treatment Plant is protecting the quality of your drinking water.

Is my water safe to drink?

Yes, water served by the JWC Water Treatment Plant is safe to drink and use.

The drinking water exceeds all regulatory testing requirements and minimum compliance standards set by the Environmental Protection Agency’s (EPA) Safe Drinking Water Act.

What is Cryptosporidium?
Cryptosporidium is a protozoan—a slightly more complex type of organism than a bacterium or virus. It can live in the intestines of humans or animals.

Outside of the body, Cryptosporidium is protected by an outer shell called an oocyst. Once the oocyst is consumed—in food or water—the organism can emerge from the shell and infect the lining of the intestine, causing an illness called cryptosporidiosis. The symptoms include diarrhea, nausea, vomiting, and abdominal cramping.

The principle source of Cryptosporidium contamination is believed to be animals, both domestic and wild. Cryptosporidium is common in the environment, including surface waters, and the finding of low numbers of oocysts in raw water is not unusual.

How is Cryptosporidium treated?
Cryptosporidium is difficult to treat with disinfection alone because the oocyst’s hard outer shell must be broken in order to be inactivated. Oocysts can survive chlorine treatment, which means that Cryptosporidium resists conventional disinfection methods.

Filtration, combined with disinfection, has a high effectiveness in removing Cryptosporidium.
The JWC Water Treatment Plant uses this method to protect the quality of your drinking water.

What’s being done to protect our drinking water in Washington County?

Source water is drawn from the Tualatin River into the JWC Water Treatment Plant and undergoes
a complex filtration and disinfection process before being distributed to JWC customers.

The filtration process consists of a series of steps, including the removal of turbidity which is the best protection against Cryptosporidium.

In comparison, water from the Bull Run Watershed is not filtered before being distributed to Portland Water Bureau customers but does undergo a treatment process.

Where does my water come from?

Click here to determine your water provider.

City of Hillsboro
Joint Water Commission partner
City of Hillsboro customers receive water from two sources:

  1. JWC Water Treatment Plant (Upper Tualatin River)
  2. Cherry Grove Slow Sand Filter Plant (Upper Tualatin River)

More Information

City of Beaverton
Joint Water Commission partner
City of Beaverton customers receive water from one source:

  1. JWC Water Treatment Plant (Upper Tualatin River)


More Information

City of Forest Grove
Joint Water Commission partner

City of Forest Grove customers receive water from two sources:

  1. JWC Water Treatment Plant (Upper Tualatin River)
  2. Watercrest Road Water Treatment Plant (City-owned watershed)

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Tualatin Valley Water District (TVWD)
Joint Water Commission partner

TVWD customers receive water from two sources:

  1. JWC Water Treatment Plant (Upper Tualatin River)
  2. Portland Water Bureau (Bull Run Watershed)

More Information

City of Cornelius
City of Cornelius customers receive water from one source:

  1. JWC Water Treatment Plant (Upper Tualatin River)

More Information

City of North Plains
City of North Plains customers receive water from one source:

  1. JWC Water Treatment Plant (Upper Tualatin River)

More Information

L.A. Water Co-op
L.A. Water Co-op customers receive water from two sources:

  1. JWC Water Treatment Plant (Upper Tualatin River)
  2. Cherry Grove Slow Sand Filter Plant (Upper Tualatin River)

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City of Gaston
City of Gaston customers receive water from two sources:

  1. JWC Water Treatment Plant (Upper Tualatin River)
  2. Cherry Grove Slow Sand Filter Plant (Upper Tualatin River)

More Information

Is the JWC monitoring for Cryptosporidium?
The protection of public health is the highest priority of the JWC Water Treatment Plant.

The JWC Water Treatment Plant currently monitors for Cryptosporidium, E. coli,
and turbidity in the source water once per month.

This monitoring is required by the Environmental Protection Agency (EPA) in order to determine if the JWC Water Treatment Plant source water is vulnerable to Cryptosporidium contamination. 

Has Cryptosporidium ever been detected in JWC source water?
The JWC’s testing of source water from the upper-Tualatin River has detected small amounts of these organisms, but the filtration and treatment process prevents the organisms from causing public health issues for JWC water customers.

Since April 2015, 22 required monthly samples have been tested. Results have ranged from non-detection to 0.3 oocysts/L. The current average of all tests are well below the limit and requires no additional treatment due to the conventional filtration method used.

Where can I learn more?
For general Cryptosporidium information, visit the Centers for Disease Control (CDC) and Prevention webpage.

Customers with severely weakened immune systems are encouraged to seek specific advice about drinking water from their personal health care providers. Information for people with severely weakened immune systems is also available from the Safe Drinking Water Hotline at 800-426-4791.

Safe Drinking Water

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