In general, draining this type of pool is the trickiest. Inground pools made of concrete or gunite are susceptible to popping out of the ground if drainage is not done properly. If there has been a surplus of rain recently or your pool is located in a wet area, it is best not to try and drain the pool yourself at all.
Concrete Pools
Once water is removed (and subsequently, the interior hydrostatic pressure), if there's an influx of groundwater, it will push the pool up and out of place. As a general rule, you shouldn't keep any pool empty for longer than it needs to be.
An inground pool can pop regardless of type. Concrete, gunite, vinyl, fiberglass—they're all at risk of popping when drained. If it's time to drain your pool, and you want to keep it from popping, consider draining just half the water from the pool, and refilling it.
If ground water is not a problem a pool can be left empty for weeks or even months as long the hydrostatic relief in the bottom of the pool is open and functioning. If the time frame of the pool being empty gets into freezing weather there is real risk of freeze-thaw damage to surface of the pool.
Close the pool for winter – but don't drain it.
In winter, the water in your pool is still your friend. Especially when properly winterized, it helps to protect the pool liner, keep it clean and prevent unnecessary damage from debris, harsh weather and other factors.
Pool industry experts recommend you drain your pool and refill it every five to seven years. No two pools are alike, so there is no set number at which you must drain your pool.
It's not good to leave your pool empty when the weather gets cold. Leaving your pool filled with water can help prevent your vinyl or concrete foundation from being damaged.
Hydrostatic pressure, or water pushing upwards, is the reason why pools can pop up out of the ground. To alleviate this problem, the majority of concrete pools are built with a hydrostatic relief valve.
An empty pool (or as little as 1/4 filled) and an exposed liner on a hot day can cause the liner to shrink from the heat and deem the liner useless. An empty pool is also susceptible to collapse. Especially, in high winds and/or bad weather.
Flooding Your Grass Is Not A Good Idea
The problem with draining your pool in the yard, if permitted by your local water regulatory laws, is that it will quickly reach its saturation level and increase the risk of flooding your lawn, drowning the roots of your grass, and attracting mosquitoes.
It typically costs $500 to $700 to drain and clean a pool and usually takes several days. Since it's more expensive, a pool company will try other common treatments to clean the pool first.
An empty swimming pool can pop, or float out of the ground. This is due to possible hydrostatic pressure from unknown underground water.
Closing a pool that is green with algae, or dirty with debris or with water that is unbalanced, leads to heavy staining and saturation of the water with dead algae cells, which makes it easier for subsequent generations to grow.
Well maintained pool water can last up to 5, maybe even seven years before you need to replace it. This means weekly cleaning, functional filters, and checking ph levels every day. Usage is a huge determining factor.
Vinyl pools tend to contract when emptied, which can result in damage when they are refilled. Gunite or fiberglass pools can crack, and fiberglass pools may suffer bulging or splitting if drained.
A well-maintained concrete pool should last around 50 years or more. And a well constructed in-ground concrete swimming pool should last a lifetime. But, a pool's liner or finish won't last long. And thus, an in-ground concrete pool will need to be resurfaced every 10 to 15 years.
Even with proper and regular pool maintenance, it's often necessary to drain your pool — completely or partially — every 3-5 years. Draining your pool often isn't necessary, especially if you're following a proper and regular maintenance program.
A well-maintained swimming pool that does not have any leaks should not have to be drained or refilled every year—even every two or three years.
If your pool has outlived its usefulness and it would cost more to repair than you can afford, you can cover it. Building a deck over a pool presents a challenge similar to any raised deck, so be prepared for hard work, sore muscles and a great sense of accomplishment.
Doing the pool maintenance yourself may reduce your costs slightly, but not necessarily as much as you might expect. Firstly, you'll need to purchase all the cleaning supplies, chemicals and equipment to carry out the clean. To purchase the just the chemicals, can cost you around $30 per month.