Water Quality

Water Quality Report 2024

• Each year the City of Gresham provides the Drinking Water Quality Report to all of its customers.
• The report contains important information about Gresham’s drinking water and water system.
• The 2024 Drinking Water Quality Report contains results from the 2023 calendar year.
• A paper copy or translation of the report can be requested by calling 503-618-2525.

Gresham’s drinking water comes from three sources:

• The Bull Run Watershed, located in a protected area of the Mt. Hood National Forest, managed by the Portland Water Bureau.
  
  
• The Columbia South Shore Well Field, also managed by the Portland Water Bureau, is used on occasion to supplement the Bull Run. Groundwater from these wells comes from three different aquifers:      
  • Blue Lake Aquifer
  • Troutdale Sandstone Aquifer
  • Sand and Gravel Aquifer
• The Cascade Well Field, managed by Rockwood PUD and the City, taps into the Sand and Gravel Aquifer. Currently, this groundwater is used to supplement our supply from the Portland Water Bureau. 
  
  
• In 2020 The City and Rockwood Water People’s Utility District formed the Cascade Groundwater Alliance to expand Gresham’s groundwater system together. The new water system is under construction and will be complete in 2026. Learn more about the Cascade Groundwater Alliance.

Water quality update

• Gresham’s primary source of water is the Bull Run watershed, a federally protected water source managed by the City of Portland. Gresham has two additional water supplies if needed.
• Recent Bull Run water monitoring results detected small levels of Cryptosporidium. At this time, there is no evidence of an increased health risk.
• The City of Gresham will continue to monitor water quality reports in coordination with Portland and local health agencies. 

Precautions customers can take 

• People with severely weakened immune systems should seek specific advice from their health care providers about drinking water.
• You can use a filter. Make sure that it is labeled and certified to remove Cryptosporidium and is NSF/ANSI 53 or 58 rated. Look for the language “cyst reduction” or “cyst removal.” Reverse osmosis and carbon filters are the most common types of filters available. Make sure that the manufacturer states “absolute” pore size of 1 micron or smaller.

Resources

• Portland Water Bureau information on Cryptosporidium
• Portland Water Bureau Cryptosporidium monitoring update
• Centers for Disease Control and Prevention (CDC)

• The Portland Water Bureau is your best source for the latest information on the situation. Customers with questions regarding water quality can call the Water Line at 503-823-7525.

Keep our groundwater safe

Join the City in protecting groundwater, our secondary source of drinking water. Groundwater is runoff from rain or other precipitation that soaks into soil, filling cracks in beds or rock deep underground, called aquifers. If we’re not careful, small amounts of chemicals – either spilled, leaked or dumped – can find their way into our aquifers.  

How you can help

• Take care when storing or disposing household chemicals. Never pour them down a storm drain. 
• Know if your older home has an underground heating oil tank. Check underground storage tanks for leaks.
• Report chemical spills and illegal dumping.
• Businesses have specific requirements for storing and using chemicals and is managed by the Groundwater Protection Program.