Quick answer: is Portland water hard or soft?
Portland water is soft. The Portland Water Bureau says Bull Run water, the city's main supply, typically has a total hardness of 7 to 11 parts per million, about half a grain per gallon. Its test results table lists 7 mg/L of hardness and 29 mg/L of total alkalinity for 100% Bull Run water. For coffee, that is far less mineral content than the Specialty Coffee Association asks for in its cupping water.
The bureau also runs a second source, the Columbia South Shore Well Field. That groundwater is moderately hard, about 80 ppm by the bureau's own description. When the bureau blends it in, usually in summer and fall, your tap water changes and so can your cup.
Portland's water next to the SCA cupping range
The first three columns come from the Portland Water Bureau's comparison of its two sources, last updated July 28, 2026. The last column is Table 2 of SCA Standard 102-2024, the water the SCA says cuppers should use whenever possible.
| Measure | 100% Bull Run | 65% Bull Run, 35% groundwater | 100% groundwater | SCA cupping water |
|---|---|---|---|---|
| Hardness as CaCO3 | 7 mg/L | 28.1 mg/L | 68 mg/L | Calcium hardness 50 to 175 ppm |
| Total alkalinity as CaCO3 | 29 mg/L | 50.7 mg/L | 91 mg/L | At or near 40 to 70 ppm |
| pH | 8.8 | 8.6 | 8.2 | 6 to 8 |
| Total dissolved solids | 60 mg/L | 82.75 mg/L | 125 mg/L | Not in the table |
Two cautions. The bureau reports total hardness, while the SCA row is calcium hardness only, so the comparison is a rough one. And Wikipedia's hard water table treats mg/L and ppm as the same unit, which is why the two sources can be read side by side.
By the U.S. Geological Survey classes that Wikipedia's hard water article reproduces, anything from 0 to 60 mg/L counts as soft and 61 to 120 as moderately hard. Pure Bull Run water sits at the very bottom of the soft class. Straight groundwater lands just inside moderately hard.
Where Portland's water comes from
The Bull Run Watershed is a protected surface supply in the Mount Hood National Forest, 26 miles from Portland. The bureau says it gets about 135 inches of rain and snow in a typical year, which runs into two reservoirs holding nearly 10 billion gallons. The U.S. Geological Survey explains that water picks up calcium and magnesium as it moves through soil and rock, which is why hardness is mostly a groundwater issue. The two columns above show the difference.
The Columbia South Shore Well Field is the backup: 25 active wells in three aquifers between Portland International Airport and Blue Lake Park. The bureau uses it to supplement Bull Run in summer and fall, and to replace it during turbidity events, maintenance and emergencies. In 2026 it ran a routine groundwater operation from August 4 and returned to 100% Bull Run water on August 21. The bureau noted that the switch back can take up to two weeks to reach every tap.
Treatment adds a little too. Sodium carbonate and carbon dioxide go into Bull Run water, and sodium hydroxide into groundwater, to cut corrosion of metals such as lead in household plumbing. Chlorine disinfects, and ammonia is added to make the chlorine last longer. The bureau puts the pH of Portland's tap water between 8.0 and 9.0.
One change is on the way. Portland is building a filtration facility for Bull Run water to remove Cryptosporidium and expects it online in 2029. The pages we read do not say how filtration will change the mineral numbers.
What soft water means for your coffee
Wikipedia's coffee preparation article lists the character of the water itself among the things that decide how coffee extracts, next to grind, temperature, contact time and brew ratio. The SCA's cupping range is one way to see what that means in practice: its standard wants noticeably more calcium hardness and alkalinity than Bull Run carries, and no chlorine at all.
Soft water has one clear upside: little scale. Hard water leaves limescale in kettles and water heaters, Wikipedia's hard water article explains, and Portland's Bull Run supply leaves very little. Your kettle and brewer need descaling far less often than they would in a hard water city.
The National Coffee Association gives plain advice in its pour-over guide: use cold water, filtered if possible, and avoid distilled or softened water. Bull Run water is not softened. It arrives soft. But Wikipedia puts fresh water at around 60 ppm of hardness in general, and Bull Run carries about a ninth of that, so it is worth a taste test before you blame your beans.
Practical fixes for Portland kitchens
- Run a side by side. Brew the same coffee, same grind and same ratio, once with tap water and once with a bottled water whose label lists its minerals. If the bottled cup tastes rounder, your water is part of the story.
- Filter if you can. The SCA lists chlorine at none for cupping water, and Portland disinfects with chlorine plus ammonia. The NCA's guide says to use filtered water where possible.
- Watch the calendar. If a coffee you know tastes different in August, check the bureau's news page. A groundwater blend roughly quadruples the hardness, from 7 to 28.1 mg/L at the 65 to 35 mix the bureau publishes.
- Adjust the grind before the water. The NCA's fix for a flat, watery cup is a finer grind, and a sour or bitter one points the other way. Change one thing at a time. Our home coffee tasting guide shows how to taste two cups side by side.
A Portland roast named for the watershed
Bull Run shows up in the coffee as well as the tap. Water Avenue Coffee sells a flagship blend called Bull Run and a decaf called Velvet Falls, which it describes as a water processed version of that blend. Water Avenue has been owned by Harder Day Coffee since August 2024, Willamette Week reported. Many of the Portland roasters we list, from Coava to Heart, have cafes in the city, so you can taste a roaster's coffee as its own baristas brew it before you buy a bag. Our guide to where to drink Portland roasters' coffee lists them by neighborhood. A listing does not mean a roaster is part of the club.
Good water only helps if the coffee is fresh. A bag roasted a few miles away gets to your kettle sooner than one shipped across the country, and the money stays with a roaster and crew here. The Multnomah Coffee Club sends a 12 oz bag from a different independent Oregon roaster each box, every 2 or 4 weeks, at $16.99 a bag. Your first bag is free; you pay $7.99 shipping on that first box. For water in Eugene, Bend, Medford and other cities, see our Oregon tap water and coffee guide.
Portland water and coffee questions
How hard is Portland tap water?
Soft. The Portland Water Bureau says Bull Run water typically has 7 to 11 ppm of total hardness, about half a grain per gallon. Its groundwater is moderately hard, about 80 ppm, and is blended in at times, mostly in summer and fall.
Is Portland water good for making coffee?
It is clean and low in minerals, and it causes very little scale. It carries far less hardness and alkalinity than the SCA's cupping water range of 50 to 175 ppm calcium hardness and 40 to 70 ppm alkalinity, so a side by side test with a mineral water is worth doing.
Does Portland add fluoride to its water?
No. The bureau says fluoride occurs naturally in its water at very low levels and is not added.
Should I use distilled water for coffee in Portland?
The National Coffee Association advises against distilled or softened water for brewing. Use cold tap water, filtered if possible.
Sources
- Portland Water Bureau, 2026 Drinking Water Quality Report (2025 results; Bull Run 7 to 11 ppm hardness, groundwater about 80 ppm; pH 8.0 to 9.0; 26 miles, 135 inches, nearly 10 billion gallons; 25 wells in three aquifers; treatment chemicals; no added fluoride; filtration by 2029)
- Portland Water Bureau, Drinking Water Test Results (source comparison table updated July 28, 2026: hardness, alkalinity, pH and dissolved solids for each blend)
- Portland Water Bureau, return to 100 percent Bull Run water (August 4 to 21, 2026 groundwater operation; up to two weeks to reach every tap)
- Specialty Coffee Association, Standard 102-2024 (Table 2, specifications of water for cupping)
- National Coffee Association, Pour-over coffee (cold, filtered water; avoid distilled or softened; grind fixes)
- Wikipedia, Hard water (USGS hardness classes; fresh water generally around 60 ppm; mg/L and ppm; limescale in kettles)
- U.S. Geological Survey, Hardness of water (water dissolves calcium and magnesium from soil and rock; groundwater systems)
- Wikipedia, Coffee preparation (water character as an extraction variable)
- Water Avenue's Bull Run and Velvet Falls coffees: the roaster's own pages as summarized on our roaster profile, checked 2026-09-27. Ownership: Willamette Week, August 19, 2024, and Wikipedia, Water Avenue Coffee.
By Joe McRose, Multnomah Coffee Club. Updated . Portland Water Bureau: 2026 Drinking Water Quality Report, Drinking Water Test Results (table updated July 28, 2026) and August 2026 groundwater press releases; SCA Standard 102-2024 for cupping water; National Coffee Association brewing guide; Wikipedia's hard water article for the USGS hardness classes.