Top 10 Plumbing Problems and How to Prevent Them

Plumbing problems rarely announce themselves politely. A drip you have been ignoring for a month turns into a stained ceiling, and a slow drain turns into a sewer backup on a Sunday night.

Bellevue makes this trickier than most places. Mid-century homes and new construction sit side by side in the same neighborhoods, so a single street can have galvanized steel supply lines in one house and PEX in the next. Add wet winters and the occasional hard freeze, and you get a specific set of failures that show up again and again.

By Ramin Shahbaziasl, Owner, Eastside Repipe & Plumbing · Last updated June 22, 2025

At Eastside Repipe & Plumbing, we have spent three decades working on these systems. Below are the ten problems we see most often, what causes each one, and what actually prevents them.

Jump to a problem: Dripping Faucets · Clogged Drains · Running Toilets · Low Water Pressure · Leaky Pipes · Water Heater Failure · Sewer Backups · Sump Pump Failure · Burst Pipes · Water Hammer

1. Dripping Faucets

A faucet that drips once per second wastes more than 3,000 gallons of water a year, according to the EPA's WaterSense program. That is roughly 180 showers going down the drain from a fixture you walk past every day.

What Causes a Dripping Faucet

• Worn washers, O rings, or cartridges

• A faucet installed slightly out of alignment

• Water pressure running higher than the fixture is rated for

How to Stop Faucets From Dripping

• Replace washers and cartridges every few years rather than waiting for failure

• Install a pressure regulator if your household pressure runs above 80 psi

• Close taps firmly but without forcing them, which wears the seat faster

2. Clogged Drains and Toilets

Clogs form when debris narrows the pipe until water cannot move through it. Kitchen lines usually clog from cooking grease that cools and hardens on the pipe wall. Bathroom lines clog from hair bound together with soap scum.

What Typically Causes Clogs

• Hair, food scraps, and excess toilet paper

• Wipes, cotton products, and hygiene items that do not break down

• Grease poured down the kitchen sink

How to Prevent Clogged Drains

• Fit mesh screens over every drain, especially in showers

• Never flush wipes, even ones labeled flushable

• Pour cooking grease into a container and bin it once it solidifies

• Flush drains weekly with hot tap water. Skip boiling water, which can soften PVC joints and crack porcelain

• Book professional drain maintenance if a drain slows repeatedly

For a deeper walkthrough, see our guide on how to prevent clogged drains.

3. Running Toilets

A toilet that runs continuously can waste hundreds of gallons a day, and because the sound fades into background noise, most homeowners do not notice until the utility bill arrives.

What Makes a Toilet Run

• A worn or warped flapper that no longer seals

• A fill valve that fails to shut off

• A float set too high, sending water into the overflow tube

How to Prevent a Running Toilet

• Drop a dye tablet in the tank twice a year. Color appearing in the bowl within 15 minutes means the flapper is leaking

• Replace flappers and fill valves every five to seven years

• Have your household water pressure checked, since high pressure shortens the life of every valve in the house

4. Low Water Pressure

If your shower trickles instead of sprays, the cause is usually restriction somewhere between the meter and the fixture.

What Causes Low Water Pressure

• Sediment and mineral scale inside aerators, showerheads, or the pipes themselves

• A hidden leak diverting water before it reaches the fixture

• Corrosion narrowing the interior of older galvanized supply lines

• Municipal supply work in your area

How to Restore Water Pressure

• Soak aerators and showerheads in white vinegar overnight to dissolve scale

• Check whether pressure dropped at one fixture or throughout the house. One fixture points to a local blockage, whole house points to a supply problem

• Have the system inspected for corrosion or leaks

• Consider larger diameter piping during a repipe if the pipes themselves are the restriction

5. Leaky Pipes

Leaks inside walls and ceilings are the most expensive problem on this list, because the damage compounds quietly for weeks before anything becomes visible.

What Causes Pipes to Leak

• Freezing temperatures expanding water inside the pipe

• Joints and fittings loosening over time

• Corrosion eating through the pipe wall from the inside

How to Catch Leaks Early

• Insulate pipes in crawl spaces, garages, and exterior walls

• Check under every sink once a month for damp cabinet bases or mineral crust on fittings

• Watch for bulging drywall, a musty smell, or a water bill that climbs without a change in habits

• Read your water meter, use no water for two hours, then read it again. Any movement means a leak

• Schedule an annual general plumbing inspection

Our guide to detecting a hidden water leak covers the diagnostic steps in more detail.

6. Water Heater Problems

Losing hot water is usually the last symptom, not the first. The unit typically signals trouble for months beforehand.

Signs Your Water Heater Is Failing

• Popping, rumbling, or crackling from the tank

• Rusty or discolored hot water

• Hot water that runs out faster than it used to

• Moisture pooling around the base

What Causes Water Heater Failure

• Sediment collecting at the bottom of the tank and insulating the burner

• Heating elements or thermocouples burning out

• Age, since most tank units last eight to twelve years

How to Extend Water Heater Life

• Flush the tank once a year to clear sediment

• Set the thermostat to 120°F, which is hot enough for household use and reduces scale buildup

• Test the pressure relief valve annually

• Replace the anode rod every few years to slow corrosion inside the tank

If yours is showing symptoms, our post on when to replace a water heater covers the repair or replace decision.

7. Sewer System Backups

Foul smells, gurgling drains, and multiple fixtures backing up at once all point to the main line rather than any single drain.

What Causes Sewer Backups

• Tree roots finding joints in clay or cast iron laterals

• Pipe sections that have cracked, sagged, or collapsed

• Years of grease and non degradable items narrowing the line

How to Prevent Sewer Backups

• Have the main line camera inspected every one to two years, especially with mature trees on the property

• Keep wipes, paper towels, and hygiene products out of the toilet

• Use root inhibitor treatments where trees sit near the sewer run

• Call for emergency service at the first sign of backup rather than waiting to see if it clears

More warning signs are covered in our guide to sewer line problems you should not ignore.

8. Sump Pump Failure

Homes with basements or crawl spaces rely on a sump pump through the wet season, and pumps almost always fail on the night you need them most.

Signs of Sump Pump Trouble

• The pump does not start when the pit fills

• It runs constantly, or cycles on and off rapidly

• Standing water or a musty smell in the pit area

• Grinding or rattling while running

How to Keep a Sump Pump Reliable

• Test it before every rainy season by pouring a bucket of water into the pit

• Clear debris from the pit and check that the discharge line is not blocked or frozen

• Install a battery backup, since heavy storms and power outages arrive together

• Replace the unit around the ten year mark

9. Burst Pipes

A burst supply line can put hundreds of gallons into your home before anyone notices. In Bellevue, these cluster around the handful of hard freezes we get each winter.

Why Pipes Burst

• Water freezing and expanding until the pipe wall splits

• Sustained pressure above what the pipe and fittings are rated for

• Corrosion thinning older galvanized or copper lines

How to Prevent Burst Pipes

• Insulate every pipe in an unheated space before the first freeze

• Know where your main shutoff valve is and make sure it turns

• Keep a pressure regulator in place and check it every few years

• Replace supply lines that are visibly corroded rather than patching them

Our winterizing guide walks through the full seasonal prep.

10. Water Hammer and Noisy Pipes

That loud thud after a washing machine or dishwasher shuts its valve is water hammer, a pressure shockwave traveling back through the line. It loosens fittings and, over time, splits pipes.

What Causes Water Hammer

• Fast closing valves stopping the flow abruptly

• Pipes that are not properly strapped and can move inside the wall

• Air chambers that have filled with water and lost their cushion

How to Fix Noisy Pipes

• Install water hammer arrestors at the appliances that trigger it

• Add or tighten pipe straps to stop movement

• Bring household pressure down to the 50 to 70 psi range

• Drain the system and refill it to recharge older air chambers

Seasonal Plumbing Maintenance Checklist

Most of the problems above are cheaper to prevent than to fix. This is the rhythm we recommend to Bellevue homeowners.

Spring

• Inspect for damage left by winter freezing

• Test outdoor spigots and hose bibs for splits

• Service the sump pump before the wet season returns

Summer

• Watch water usage while sprinklers and hoses are running

• Note any odors or slow drains that suggest sewer line trouble

• Book inspections now, when scheduling is easiest

Fall

• Insulate pipes in garages, crawl spaces, and exterior walls

• Drain and shut off outdoor faucets before the first freeze

• Clear gutters so overflow does not pool against the foundation

Winter

• Hold indoor heat at 55°F or above when traveling

• Open cabinet doors under sinks on exterior walls during cold snaps

• Let a faucet drip on the coldest nights to relieve pressure

When to Call a Professional Plumber

Some of the fixes above are genuinely DIY. Call a licensed plumber when you see any of the following:

• Water stains, mold, or a musty smell near plumbing fixtures

• A sudden drop in pressure across the whole house

• Drains that back up repeatedly after clearing

• A utility bill that jumps without a change in usage

• Any puddle or damp patch you cannot trace

These indicate problems inside the system rather than at the fixture, and waiting generally means paying for both the plumbing repair and the water damage.

Before hiring anyone in Washington, you can confirm their license, bond, and insurance for free through the state Department of Labor and Industries. Our guide to plumber costs in Bellevue covers what a fair quote looks like, and emergency plumbing tips covers what to do in the first ten minutes.

Frequently Asked Questions

What is the most common plumbing problem in homes?

Dripping faucets and clogged drains are the two we get called for most. Both are inexpensive to fix early and both waste a surprising amount of water if left alone.

How often should I have my plumbing inspected?

Every one to two years for most homes. Annually if your house was built before 1980, still has galvanized supply lines, or has a history of leaks or backups.

Can I use chemical drain cleaner on a slow drain?

We advise against it. Chemical cleaners often clear just enough to restore flow while leaving the blockage in place, and repeated use corrodes older pipes and damages some PVC joints. A drain that slows repeatedly needs mechanical clearing or hydro jetting.

How do I know if a leak is inside my walls?

Check your water meter, avoid all water use for two hours, then check it again. Movement with everything off means water is escaping somewhere. Bulging drywall, a musty smell, or warm spots on the floor are other common signs.

What should I do first if a pipe bursts?

Shut off the main water valve, then cut power to any affected area if water is near outlets or the panel. Call for emergency service after the water is off, not before.

Are flushable wipes actually flushable?

No. They pass through the toilet but do not break down the way toilet paper does, and they are a leading cause of the main line clogs we clear.

Staying Ahead of Plumbing Problems

Nearly everything on this list starts small and stays cheap for a while. The difference between a fifteen-dollar flapper and a four-thousand-dollar restoration job is usually just how long the problem went unnoticed.

Build the seasonal checks into your routine, act on the early signs, and bring in a professional when the problem sits inside the system rather than at the fixture.

Ready to get ahead of it? Book an inspection or call 425-331-2011. We help Bellevue and Eastside homeowners keep their plumbing working year-round.