If you’ve noticed your pool losing water faster than usual, you’re not alone. During the summer months, one of the most common questions we hear from homeowners throughout Milton, Colchester, Essex, St. Albans, and surrounding Vermont communities is:
“Why is my pool losing water?”
While some water loss is completely normal, excessive water loss can signal a problem that should be addressed before it leads to costly repairs, higher water bills, or damage to your pool equipment.
At Avalon Pools & Spas, we’ve helped Vermont pool owners diagnose and fix water loss issues for years. Here’s what you need to know.
How Much Water Loss Is Normal?
Before assuming you have a leak, it’s important to understand that all swimming pools lose some water naturally.
During a typical Vermont summer, pools can lose approximately ¼ to ½ inch of water per day due to:
- Evaporation
- Wind
- Hot temperatures
- Low humidity
- Splashing from swimmers
- Backwashing filters
If your pool is losing more than about 2 inches of water per week, it’s time to investigate further.
The Most Common Reason Your Pool Is Losing Water: Evaporation
Evaporation is the number one cause of water loss in swimming pools.
Several factors can increase evaporation:
Warm Days and Cool Nights
Vermont’s summer weather often creates ideal conditions for evaporation. When warm pool water meets cooler nighttime air, water naturally evaporates more quickly.
Wind Exposure
Pools located in open yards or elevated areas can lose water faster due to wind constantly moving moisture away from the water’s surface.
Heated Pools
If you use a pool heater or heat pump, warmer water temperatures can increase evaporation rates.
Low Humidity
Dry summer air absorbs moisture more readily, accelerating water loss.
How to Reduce Evaporation
Consider:
- Using a solar cover
- Installing windbreak landscaping
- Keeping water temperatures reasonable
- Covering the pool when not in use
How to Tell If Your Pool Has a Leak
If you suspect your pool losing water is more than normal evaporation, try the Bucket Test.
The Bucket Test
- Fill a bucket with pool water.
- Place the bucket on a pool step.
- Mark the water level inside the bucket.
- Mark the pool water level on the outside of the bucket.
- Wait 24-48 hours without using the pool.
If the pool water drops significantly more than the water inside the bucket, a leak may be present.
This simple test helps separate evaporation from actual water loss caused by pool damage or equipment issues.
Pool Plumbing Leaks
One of the most common service calls we receive involves underground plumbing leaks.
Your pool’s circulation system includes:
- Skimmers
- Return lines
- Main drains
- Underground pipes
- Equipment connections
Over time, shifting soil, freezing temperatures, and normal wear can cause plumbing components to crack or separate.
Signs of a plumbing leak include:
- Wet or soggy areas around the pool
- Air bubbles in return jets
- Difficulty maintaining water levels
- Unexpected increases in water usage
Because plumbing leaks often occur underground, professional leak detection may be necessary.
Leaking Pool Equipment
Sometimes the problem isn’t the pool itself—it’s the equipment pad.
Inspect your:
Pool Pump
Look for dripping water around seals, fittings, and housing components.
Filter System
Small cracks in filters, multiport valves, or connections can lead to steady water loss.
Heater
Corrosion or damaged internal components can cause water to escape unnoticed.
Salt Systems and Chlorinators
Leaks can develop around fittings and unions over time.
Even a slow drip can result in significant water loss over several weeks.
Vinyl Liner Leaks
For homeowners with above-ground or vinyl liner pools, punctures are another common cause of water loss.
Vinyl liners can be damaged by:
- Sharp objects
- Pool toys
- Pet claws
- Tree branches
- Age-related wear
Signs of a liner leak include:
- Wrinkles appearing suddenly
- Soft spots around the pool
- Water loss that continues regardless of equipment operation
Many small liner leaks can be repaired without replacing the entire liner if caught early.
Cracks in Concrete or Fiberglass Pools
In-ground concrete and fiberglass pools can occasionally develop structural issues that lead to leaks.
Potential causes include:
- Ground movement
- Freeze-thaw cycles
- Settling
- Age-related deterioration
Watch for:
- Visible cracks
- Areas that remain wet around the pool
- Water level stabilizing at a specific point
A professional inspection can determine whether repairs are cosmetic or structural.
Skimmer Leaks
The skimmer is one of the most overlooked leak locations.
Over time, the connection between the skimmer and pool wall can separate due to:
- Seasonal temperature changes
- Ground movement
- Aging materials
Signs of a skimmer leak include:
- Water loss stopping when levels drop below the skimmer opening
- Cracks around the skimmer throat
- Wet soil near the skimmer area
Because skimmers are constantly exposed to movement and weather, they are one of the first places pool professionals inspect when troubleshooting water loss.
Could Your Pool Be Losing Water Because of Splash-Out?
Sometimes the answer is simpler than homeowners expect.
If you’ve recently hosted:
- Pool parties
- Family gatherings
- Swimming lessons
- Kids playing for extended periods
Splashing can remove surprising amounts of water.
A busy weekend with lots of swimmers can easily lower water levels by an inch or more.
Before assuming there’s a leak, consider recent pool activity.
Why Fixing Water Loss Quickly Matters
Ignoring a pool leak can lead to larger and more expensive issues.
Potential consequences include:
Increased Water Bills
Constantly refilling the pool adds up quickly.
Equipment Damage
Low water levels can cause pumps to run dry, leading to costly repairs.
Chemical Imbalances
Frequent water replacement dilutes pool chemicals, making water harder to balance.
Structural Damage
Undetected leaks can erode soil, damage decking, and affect the pool’s foundation.
The sooner a leak is identified, the easier and less expensive it typically is to repair.
Professional Pool Leak Detection in Vermont
If your pool is losing water and you can’t determine the cause, professional leak detection can save time, money, and frustration.
At Avalon Pools & Spas, we help homeowners throughout Milton, Colchester, Essex, St. Albans, Burlington, and surrounding Vermont communities identify and resolve pool water loss issues.
Whether the problem is evaporation, plumbing, equipment, liners, or structural damage, our experienced team can diagnose the issue and recommend the appropriate solution.
Contact Avalon Pools & Spas
If you’re noticing your pool losing water faster than normal, don’t wait until a small issue becomes a major repair.
The team at Avalon Pools & Spas can help determine whether you’re dealing with normal evaporation or a leak that needs professional attention.
Contact us today to schedule pool service and keep your pool operating efficiently all summer long.
Frequently Asked Questions
Why is my pool losing water every day?
Some daily water loss is normal due to evaporation, especially during hot, sunny, or windy weather. However, if your pool is losing more than ¼ to ½ inch of water per day, there may be a leak that requires further investigation.
How much water loss is normal in a swimming pool?
Most pools lose between 1 and 2 inches of water per week from evaporation and normal use. Heated pools and pools exposed to wind may lose slightly more.
How do I know if my pool is losing water from evaporation or a leak?
The easiest way to tell is by performing a Bucket Test. If the pool water level drops more than the water inside the bucket over a 24-48 hour period, a leak is likely present.
Can a pool leak cause my water bill to increase?
Yes. Even a small leak can waste thousands of gallons of water over time, resulting in higher water bills and increased chemical costs.
What are the most common places a pool leaks?
Pool leaks commonly occur in:
- Skimmers
- Return fittings
- Underground plumbing lines
- Pool pumps and filters
- Vinyl liners
- Lights and pool penetrations
- Cracks in concrete or fiberglass pools
Why is my pool losing water after I run the pump?
If water loss increases while the pump is running, the issue may be related to your plumbing system, filter, heater, or other equipment components rather than the pool shell itself.
Can a vinyl liner pool develop leaks?
Yes. Vinyl liners can be punctured by sharp objects, pets, tree branches, or general wear and tear. Small holes can often be repaired if identified early.
Is it normal for a pool to lose water during a heat wave?
Absolutely. High temperatures, direct sunlight, low humidity, and wind can significantly increase evaporation rates, causing your pool to lose water faster than normal.
Can a pool lose water from splashing?
Yes. Active swimmers, pool parties, water games, and cannonballs can all contribute to noticeable water loss, especially during busy summer weekends.
When should I call a pool professional about water loss?
You should contact a pool professional if:
- Your pool loses more than 2 inches of water per week
- You notice wet spots around the pool
- Air bubbles appear in your return jets
- Water levels continue dropping despite limited pool use
- You suspect a plumbing or equipment leak
Does Vermont’s winter weather cause pool leaks?
Freeze-thaw cycles can sometimes contribute to cracked plumbing lines, damaged fittings, or structural movement over time. This is one reason why proper pool closing and winterization are important for Vermont homeowners.
Can a leaking pool damage my property?
Yes. Undetected leaks can erode soil, damage pool decks, create soft spots in your yard, and potentially impact the structural integrity of your pool over time. Properly diagnosing and repairing leaks early can help prevent more extensive repairs later.
