When you picture a new swimming pool going into your Tampa Bay backyard, you probably think about the shape, tile, water features, decking, and maybe that perfect tanning ledge.
But one of the most important parts of your pool is something you’ll rarely see once construction is finished:
The ground underneath it.
Florida’s sandy soil, heavy summer rainfall, and groundwater conditions can create challenges that aren’t as common elsewhere in the country. That’s one reason choosing an experienced Tampa Bay pool professional matters. Building a pool isn’t simply a matter of digging a hole and filling it with concrete. The builder needs to understand the conditions below your backyard, too.
Tampa Bay Soil Isn’t Like Soil Everywhere Else
Much of Florida has sandy soils that allow water to move through the ground relatively easily. While that can be beneficial for drainage in some situations, sand can also shift, erode, or become unstable when disturbed.
Digging a large swimming pool changes the conditions of the surrounding soil. A professional pool builder needs to consider the stability of the excavation, the condition of the underlying soil, drainage, and groundwater before and during construction.
In other words, what’s underneath your pool can be almost as important as the pool itself.
You can get a pretty good idea of whether a backyard is likely to support a pool, but you generally can’t know for certain just by looking at the yard. In the Tampa Bay area, soil and groundwater conditions can vary significantly even between nearby properties.
Some clues homeowners can look for include:
- Standing water after rain that remains for a long time — this can indicate poor drainage or a high water table.
- Very loose, sandy soil — common around Tampa Bay. Sand itself doesn’t mean you can’t build a pool, but excavation and stabilization may require special care.
- Soft or sinking areas in the lawn, driveway, patio, or around the foundation.
- Cracks or settlement in existing patios, decks, retaining walls, or foundations.
- A low-lying backyard or property near ponds, canals, wetlands, or other bodies of water, where groundwater may be closer to the surface.
- Previous fill dirt — some lots have been substantially filled or altered during earlier construction, so the soil beneath the surface may not be what you expect.
- Known sinkhole or subsidence activity in the surrounding area.
Sandy Soil Can Shift During Excavation
Dig a hole in dense soil, and the sides may remain relatively firm. Dig into loose sand, and it’s a different story.
Sand can move or collapse during excavation, particularly when water is present. Pool contractors therefore need to understand how to safely excavate the site and prepare it for construction.
The goal isn’t simply to create a pool-shaped hole. The excavation and base need to provide the proper conditions for a structure that will hold thousands of gallons of water for decades.
For an actual pool project, the important question isn’t simply “Is my soil good?” It’s “What does the pool need to be designed and constructed correctly for the conditions on this particular property?”
Groundwater Can Be Surprisingly Close
Here’s something that surprises many Tampa Bay homeowners:
Your backyard can look completely dry while groundwater sits relatively close beneath the surface.
Groundwater levels can also change with rainfall and seasonal conditions.
During pool excavation, contractors may encounter groundwater entering the hole. Depending on the site conditions, managing that water can become an important part of the construction process.
Experienced local pool professionals know that groundwater isn’t necessarily an unusual surprise in Florida. It’s something that should be anticipated and handled appropriately.
Florida’s Rainy Season Changes the Equation
Anyone who has lived through a Tampa Bay summer knows how quickly a sunny afternoon can turn into a downpour.
All that rain doesn’t just fill your pool. It affects the soil around and beneath it.
After extended periods of heavy rainfall, the ground can become saturated, and groundwater levels may rise. Proper drainage around the finished pool and deck therefore becomes an important part of the overall backyard design.
Water needs somewhere appropriate to go.
Poor drainage can contribute to erosion, settling, and problems around pool decking and landscaping.
Why Proper Soil Preparation Matters
A swimming pool is a substantial structure. Once filled, it contains an enormous amount of water.
For perspective, water weighs about 8.34 pounds per gallon.
That means a 15,000-gallon pool contains roughly 125,000 pounds of water—before considering the weight of the pool structure itself.
Proper excavation, soil preparation, and construction aren’t areas where homeowners want to take shortcuts.
If soil settles or moves, problems can show up later in the decking, plumbing, drainage, or other components surrounding the pool.
The Strange Reason You Shouldn’t Simply Drain a Florida Pool
One of the most interesting consequences of Florida groundwater is something many homeowners don’t realize:
In extreme circumstances, an empty swimming pool can actually be pushed upward by groundwater.
It sounds impossible, but the principle is similar to buoyancy.
When a pool is full, the enormous weight of the water helps counteract upward pressure from groundwater. When that water is removed, the balance changes.
If groundwater surrounding the pool is high enough, hydrostatic pressure can create serious problems and potentially cause a pool shell to shift or lift.
That’s why completely draining a swimming pool—particularly during Florida’s rainy season or after significant rainfall—isn’t something homeowners should automatically do themselves.
If your pool needs to be drained for resurfacing, repairs or another reason, talk with a qualified pool professional first.
Your Neighbor’s Yard Isn’t Necessarily the Same as Yours
Another reason local experience matters is that soil and groundwater conditions can vary even within the same Tampa Bay community.
A property may contain:
- Natural sandy soil
- Previously disturbed soil
- Fill material brought onto the property
- Organic material
- Areas affected by previous construction
- Different drainage patterns
- Different groundwater conditions
Proximity to ponds, lakes, canals, wetlands, and coastal areas can add additional considerations.
So just because your neighbor’s pool construction went one way doesn’t mean your property will present exactly the same conditions.
This Is Why Professional Pool Construction Matters
There are plenty of backyard projects that make great DIY projects.
Building a swimming pool isn’t one of them.
A professionally built pool requires far more than an attractive design. Experienced pool builders consider excavation, soil conditions, groundwater, drainage, structural construction, plumbing, electrical systems, equipment placement and local building requirements.
And in Tampa Bay, local experience is especially valuable.
A contractor who regularly builds and remodels pools in the area understands the realities of Florida’s sandy soils, sudden thunderstorms, heavy summer rainfall and changing groundwater conditions.
Those aren’t minor details.
They’re part of building a pool designed to perform well in our local environment.
Build Your Tampa Bay Pool From the Ground Up
The beautiful tile, sparkling water, and finished pool deck may get all the attention, but a great swimming pool starts long before those finishing touches are installed.
It starts with what’s underneath it.
At JJB Pools & Spas, we understand that Tampa Bay pools need to be built for Tampa Bay conditions. From evaluating the property and planning your pool to construction, equipment and finishing details, working with experienced professionals can help protect your investment for years to come.
If you’re considering building or remodeling a pool in the Tampa Bay area, contact JJB Pools & Spas to discuss your backyard, your ideas, and the pool that’s right for your property.
Frequently Asked Questions About Tampa Bay Soil and Swimming Pools
Is sandy soil bad for building a pool in Tampa Bay?
Not necessarily. Pools are successfully built in Florida’s sandy conditions all the time. The important part is having the site properly evaluated, excavated, prepared, and constructed for the conditions present on the property.
Why does groundwater matter when building a Florida pool?
Groundwater can enter an excavation and may require management during construction. Groundwater conditions can also become important when an existing pool needs to be drained.
Can an empty swimming pool really pop out of the ground in Florida?
Under certain conditions, groundwater can create enough upward pressure to damage or move a pool structure. This is one reason Florida homeowners should consult a pool professional before completely draining a swimming pool.
Does Tampa’s rainy season affect swimming pool construction?
Heavy rainfall can affect excavation, soil conditions, groundwater, and construction scheduling. An experienced Tampa Bay pool contractor can account for changing weather and site conditions throughout the project.
Why should I hire a local Tampa Bay pool builder?
Local pool professionals are familiar with regional soil, groundwater, rainfall, drainage considerations, and permitting requirements. That local knowledge can be particularly valuable when constructing or remodeling a major structure such as a swimming pool.