05/27/2026
Gresham neighbors — a plumber’s take on the recent water concerns
We’ve been seeing the same conversations many of you have: low water pressure, discoloration, taste changes, smell changes, cloudy-looking water, and questions about whether this can affect the plumbing inside your home.
We wanted to offer a calm, practical plumber’s perspective from Da Vinci’s Best Plumbing.
First, this is not meant to scare anyone. The City has stated that Gresham’s water is safe to drink, and we are not here to argue against that. Safe water can still look, taste, smell, or behave differently when a water system goes through a major source, treatment, pressure, or flow transition.
Gresham is moving from primarily Bull Run surface water toward Cascade groundwater as the main water source. Groundwater naturally carries more minerals than surface water. That does not automatically mean “bad water.” It does mean homeowners may notice changes at the tap, and some of those changes can show up inside the home’s plumbing system.
Here is what that can mean in plain English.
Low or changing water pressure
Pressure issues can come from several places. Sometimes it is city-side work, flushing, hydrant use, source changes, pressure-zone changes, or neighborhood demand. Other times it is inside the home: a clogged aerator, plugged filter, old galvanized piping, failing pressure reducing valve, softener issue, water heater issue, or buildup in fixture cartridges.
If your whole-house pressure suddenly changed, the first step is not guessing. The first step is testing.
A healthy home usually wants steady pressure in a comfortable range. If pressure is too high, it can damage fixtures, valves, water heaters, supply lines, washing machine hoses, refrigerator lines, and toilet fill valves. If pressure is too low, fixtures may perform poorly and appliances may struggle.
Important: do not remove or bypass a pressure reducing valve just because pressure feels lower right now. Pressure can fluctuate. The right answer is to test the pressure and diagnose the actual cause.
Pressure reducing valves, check protection, and expansion tanks
A PRV, or pressure reducing valve, protects the home when city pressure is higher than the plumbing system should receive.
A PRV can also change how pressure behaves inside the home. Many plumbing systems with PRVs, check valves, backflow devices, or other one-way protection become what plumbers call a “closed system.” That means water can enter the home, but heated water may not be able to expand backward toward the city main.
When water heats up, it expands. If there is no place for that expansion to go, pressure can build inside the home. That extra stress can show up at the water heater, toilet fill valves, fixture cartridges, supply lines, washing machine hoses, refrigerator lines, and shutoff valves.
That is why homes with a PRV, check valve, backflow device, or other closed-system condition need approved thermal expansion protection. In many residential homes with a tank-style water heater, that usually means a properly sized thermal expansion tank.
From a plumber’s perspective, thermal expansion is usually a bigger concern with tank-style water heaters because they store a volume of heated water. With tankless systems, it depends on the setup. Recirculation systems, storage tanks, check valves, PRVs, and manufacturer requirements can all change what is needed. The important point is this: closed plumbing systems need to be evaluated properly, not guessed at.
Code matters. Good plumbers take it seriously because plumbing code exists to protect the home, the water system, and the people living there.
If the public water pressure changes, that does not automatically mean your PRV or expansion tank should be removed. It means they should be checked, tested, and adjusted if needed.
Testing an expansion tank
Before testing anything, first locate your main water shutoff valve and make sure you know how to shut off water to the home if needed. Do not guess. If you are not sure where it is, how it works, or whether it will actually shut off, call for help before messing with the system.
In most residential homes, an expansion tank is usually a small 2–4 gallon tank installed near the water heater. It looks a little like a metal balloon. It usually has a threaded connection on one side and a Schrader valve, similar to a tire valve, on the other.
The first quick test plumbers often do while the system is live is briefly press the Schrader valve.
If water sprays out of that Schrader valve, the internal bladder has failed and the expansion tank needs to be replaced.
If only air comes out, or no air comes out, that does not automatically mean the tank is good. It means the next step is checking the air charge with a pressure gauge.
A few adjustment tips:
First, use a pressure gauge on a hose bibb to determine your home’s static water pressure. Make sure no water is running inside the home during this test. Write that pressure down.
Then shut off the water to the home and relieve the water pressure by opening a hot-side faucet. After the pressure is relieved, check the expansion tank with a tire gauge at the Schrader valve.
The air pressure in the expansion tank should generally match the home’s static water pressure. If it does not, it can usually be adjusted with a bike pump or electric air pump. I recommend the electric air pump from first-hand bike pump experience.
After adjusting, test it again with the tire gauge, close the faucet, and restore water to the home.
Warning: do not over-pump the expansion tank. A little adjustment is fine, but if someone cranks it up to an extreme pressure, the bladder can be damaged.
One of my real plumbing experience examples
One of the reasons I pay close attention to pressure changes and check protection is because I have seen strange problems happen after sudden water-main events.
On one job, a customer’s neighbor had a house fire. The fire truck connected to the hydrant right in front of the customer’s home. Fire engines do not just gently open a faucet and let city pressure do all the work. They use powerful onboard pumps and can move a huge amount of water very quickly.
After the fire truck left, the customer noticed a sudden complete loss of water flow at one fixture on the hot side only. I believe it was the clothes washer.
That detail mattered.
After listening to what happened, I suspected the fire event and pressure swing had disturbed something inside the plumbing. The issue ended up being a small ball from a heat-trap ni**le on the water heater. That little ball had been pulled loose, traveled through the 1-inch and 3/4-inch PEX piping and fittings, and eventually lodged in a 1/2-inch tee feeding the upstairs laundry.
It took opening sheetrock in the garage ceiling to locate and solve it. But the key to finding it was understanding how a sudden pressure and flow event outside the home could create a very specific plumbing problem inside the home.
That does not mean every pressure change will cause that kind of issue. It does mean that when water behavior changes suddenly, the home’s plumbing system can reveal weak points, debris, old parts, failed checks, bad stops, clogged cartridges, plugged filters, or water heater components that were already close to becoming a problem.
Discolored water
Discoloration can happen when sediment or minerals in water mains get disturbed. That can happen during flushing, main work, hydrant use, pressure changes, changes in water direction, or source changes.
If you see discoloration:
Avoid washing white laundry until it clears.
Run cold water from a bathtub or hose bibb for a few minutes.
Check whether it is happening at one fixture or the whole home.
Remove and rinse faucet aerators if flow is reduced.
Report widespread or ongoing discoloration to the water provider.
If only your hot water is discolored, that may point more toward the water heater than the city supply.
Taste and smell changes
Taste and smell can change when the water source changes, when the mineral content changes, or when the disinfection method changes. Sometimes the smell is coming from the water supply. Sometimes it is coming from the home’s plumbing, water heater, filtration system, softener, or rarely used fixtures.
A simple filter can make a real difference. For many families, a refrigerator filter, faucet filter, under-sink filter, or even a good pitcher-style filter may be enough for taste concerns. For homes that want a broader solution, whole-home filtration may be worth considering.
My family uses the filter in the refrigerator and we have not noticed much change. We replace the filter every 6 months, and it works well for our taste buds.
Harder water and what it does inside a home
Groundwater commonly has more dissolved minerals than surface water. In a home, those minerals can show up as:
Spots on dishes
Film on shower doors
Less soap lather
Scale around fixtures
Buildup in aerators
More maintenance on filters
More sediment in water heaters over time
This is not the same as saying the water is unsafe. It is simply the difference between water quality from a drinking standpoint and water behavior from a plumbing standpoint.
Water heaters and anode rods
This is where water chemistry matters.
Most tank-style water heaters come with a sacrificial anode rod from the factory, commonly magnesium. The anode rod is designed to corrode before the steel tank corrodes. That is why it is called “sacrificial.”
The simple version:
The anode is the metal that gives itself up first.
The cathode is the metal being protected.
Inside a water heater, the anode rod is supposed to corrode so the steel tank does not.
Magnesium is more electrically active, so it protects aggressively. Aluminum and aluminum-zinc rods behave differently and may be better in certain water conditions, especially where odor or fast anode consumption is a concern. Powered anode rods are another option in some situations.
But this is not one-size-fits-all. Changing an anode rod does not soften water, and it does not magically fix every water issue. It is one tool that may help extend water heater life or reduce odor depending on the water chemistry and the condition of the heater.
If your hot water has a rotten egg smell, rusty color, popping sounds, heavy sediment, or repeated water heater problems, it is worth having the water heater inspected.
Flushing sediment from tank-style water heaters
It is probably going to be more important than ever to flush sediment out of tank-style water heaters on a regular basis.
This can usually be done by hooking up a garden hose to the drain valve at the bottom of the water heater and running the hose to a safe draining location, such as a driveway or road.
Do not drain hot water onto the lawn or near plants. Hot water can damage or kill vegetation. Do not ask me how I know. I will just say I was a rookie once.
In many cases, you do not need to shut off the water to the water heater for a basic pressure flush. You can open the drain valve and let the water pressure help push sediment out. If the buildup is heavy, the drain valve may clog. Sometimes opening and closing the drain valve will free it up. If it does not, you may need a plumber or a tool designed for that exact purpose.
Also, be careful. Water coming from a water heater can be dangerously hot. Make sure the hose is secure, the discharge location is safe, and no kids, pets, or people are near the hot discharge water.
A personal note
I grew up in Eastern Oregon, in Harney County, where some homes deal with truly aggressive water. At my mom’s house, the water has been so mineral-heavy and corrosive that water heaters can fail unusually fast and build extreme mineral deposits in a short amount of time.
Gresham’s situation is not that.
But that experience does give me respect for water chemistry. Even when water is safe to drink, changes in minerals, pressure, treatment, and flow can affect plumbing systems over time. The smart move is not panic. The smart move is awareness, testing, and maintenance.
What homeowners can do right now
Check whether the issue is hot water, cold water, or both.
Check whether it is one fixture or the whole house.
Clean faucet aerators and shower heads.
Replace overdue refrigerator or under-sink filters.
Avoid laundry if water is visibly discolored.
Flush cold water from a tub or hose bibb if discoloration appears.
Have your home’s water pressure tested.
If you have a PRV, make sure it is working properly.
If you have a tank-style water heater and a closed plumbing system, make sure the expansion tank is properly charged and functioning.
If a fixture suddenly loses flow after a major pressure event, do not assume the fixture is the only problem. Debris or a failed internal part may have moved through the piping.
If taste is the main concern, start with simple filtration before assuming you need a major system.
If problems are sudden, widespread, or ongoing, report them to the City so they can track patterns.
When to call the water provider
Call the water provider if several neighbors have the same problem, if the water is discolored throughout the home, if pressure suddenly drops across the whole house, if there is a possible main break, or if the issue started immediately after public water work nearby.
When to call a plumber
Call a plumber if the issue seems isolated to your home, if only hot water is affected, if pressure is low at some fixtures but not others, if your PRV is old or failing, if your expansion tank is bad, if your water heater is noisy or producing discolored hot water, if filters and aerators keep clogging, or if one fixture suddenly loses flow after a pressure event.
Our goal is not to sell fear. It is to help neighbors understand what may be happening and protect their homes.
We live and work in this community too. If you are unsure whether what you are seeing is a city-side issue or a home plumbing issue, we are happy to help you think through the next step.
And yes, we named our AI receptionist Karen. She’s great at taking calls, but we don’t let her near PRVs — she keeps asking to speak to the pressure manager.
— Da Vinci’s Best Plumbing
Care you can feel, work you can trust.
Call now to connect with business.
