Free Shipping on Qualifying Orders over $99 - Get Details

Why is my swimming pool liner floating?

By Team Royal - Updated On: 10/28/23

A swimming pool is a perfect way to cool off under the hot summer sun and bring family and friends together.  Along with the summer sun also comes those pesky rainy days.

Without proper care, liners are subject to “float” during the spring and early summer due to excessive rain. But the good news is, there are ways you can prevent this from happening!

Webster defines groundwater as water within the earth. When a liner floats a lot of pool owners are told they have a groundwater issue which isn't really the case, although it's a common misconception. If the water level in the pool is higher than the water level in the ground there's enough pressure to keep the liner secured properly. 

However, high amounts of rain or melted snow (or water accumulating around a pool that reside in a low-lying area without proper drainage systems) can join with the existing groundwater and increase the water levels under your pool. This causes pressure to build and is the cause of your liner lifting.

This is hydrostatic pressure. This pressure can destroy fiberglass and lift sections of gunite pools out of the ground. However, this is where vinyl liner pools have a strong advantage over their sister pool types. A floating liner is a small issue when you compare it to the serious damage hydrostatic pressure can cause to concrete or fiberglass. 

That being said, if your liner ends up floating, once the water starts to recede, you may discover some of the following problems as well so you'll want to make sure to deal with the issue quickly: 

  • Liner coming out of the track located under the coping
  • Wrinkles on the floor and/or walls   
  • Shifting of the floor in a sand bottom pool
  • The protective wall foam between the liner and walls, bunching up around the top of the pool. If this happens, the wall foam needs to be removed.
  • Tears, especially in older liners

Never fear! Here are some tips and tricks to help prevent your liner from floating!


Vinyl liner pools built in areas that have a high water table or reside in a low-lying area require a small amount of additional planning during the pool installation period. A groundwater system would need to be installed to prevent that extra H2O from collecting between the liner and the floor of your pool.  

How Can I Prevent My Liner from Floating?

When winterizing the pool for the winter, the most common procedure is to lower the water level in the pool.  This is not recommended for vinyl-lined pools with a history of floating liners. A simply skimmer plug (Gizzmo) will protect the skimmer housing from any freeze damage. 

A drain/vacuum line can be installed to relieve the hydrostatic pressure.  This is a PVC pipe installed in the wall of the pool, under the liner, and joins on the suction side of the pump or a water drain. This way the hydrostatic pressure can be relieved as it accumulates. Groundwater pumps are another way to pull water from behind the liner.  This uses the PVC pipeline in conjunction with a combination valve box and sump pump.

Adjust your landscaping and water flow management. Landscaping, French drains and deck drains are a great source to help shuffle water away from the pool. Water will take the path of least resistence so you can use these techniques to usher it a direction away from your pool. 

How Do I Fix a Floating Pool Liner?

When groundwater floats a liner, the liner is lifted up, therefore, causing the tension to be released from the liner bead.  This allows the liner bead to become loose and eventually pulled out of the track.  If this happens, the liner bead will simply need to be reinstalled back into the track or more commonly called “snapped” back into the track.

If floating is a recurring problem, liner locks can be installed in the track along with the liner bead to make a snugger fit, leaving less room for movement.

 If your pool does not have groundwater systems in place, there’s still good news! Your local pool professional can drain the water from under the pool and reposition or “Reset” your liner if caught in time and still suggest a possible groundwater system appropriate for your pool. 


Try This New Solution to Pool Groundwater Issues

Another quick & easy solution to groundwater issues is our new HydroBlox product! 



The short version: HydroBlox moves water from where you do not want the water, to where you do want the water.


HydroBlox planks are installed in a wet area and continued on to a dry area. The water moves from plank to plank by water pressure. As one plank fills up with water, it is pushed to the next plank by water pressure. This allows you to install HydroBlox in a level area. No need for any downward installation.

HydroBlox is much stronger than pipe and will not crush over time. Unlike pipe, NO aggregate and geotextile are required. HydroBlox truly is an underground gutter system.

 Shop HydroBlox Now


Hydroblox™ maintains permeability, requires little to zero post-installation maintenance, and can easily be part of any future site developments. Here are some additional benefits that you can expect:

Avoid run off water and debris getting into your pool; doing so can

  • Cut down on chemical use
  • Lower time spent cleaning and re-balancing ph levels
  • Keep pests and creatures from riding a natural water slide into your pool

 Ward off ground water causing your liner to float

  • A floating liner is at risk of damage beyond repair

 Provide a new watering hole location for neighborhood pests to gather

  • Less itching, more swimming

 Lay as a foundation for your pool’s deck to redirect dirty water from going into your pool

You can learn more about HydroBlox or purchase them here!

Happy Swimming!!