How to Drain Pool: A Step-by-Step Guide

That sparkling oasis in your backyard brought you countless hours of fun, but now it’s looking a little green, or maybe you’re facing a repair that requires an empty pool. Draining a pool might seem like a daunting task, but it’s a necessary part of pool maintenance that, when done correctly, can prevent damage and keep your pool in tip-top shape. Understanding the proper methods and potential pitfalls can save you from costly repairs down the line, such as a pool that pops out of the ground due to hydrostatic pressure or a damaged liner from improper draining.

Whether you’re preparing for winterization, cleaning up a severe algae bloom, or addressing structural issues, knowing how to safely and effectively drain your pool is crucial. Ignoring the correct procedures can lead to serious problems, including cracked plaster, collapsed walls, or even damage to your pool equipment. This guide will provide you with the knowledge to drain your pool confidently and protect your investment.

What are the best methods for draining my pool, and what precautions should I take?

How do I properly drain my pool without damaging it?

Draining a pool requires careful planning and execution to avoid structural damage. The key is to avoid hydrostatic pressure buildup and prevent the pool from popping out of the ground. This is achieved by checking the water table level, using the hydrostatic relief valve (if equipped), and draining slowly, ideally no more than 12 inches per day.

Before you even think about draining, assess the water table around your pool. If the water table is high, draining your pool can be disastrous. High groundwater pressure can push against the empty pool shell, potentially cracking it or even causing it to float or “pop” out of the ground. You can usually gauge the water table by digging a hole a few feet deep near the pool. If it fills with water, the water table is high. If you suspect a high water table, consult with a pool professional before proceeding. They might recommend methods like dewatering techniques to alleviate the pressure. If the water table isn’t an issue, locate your pool’s hydrostatic relief valve, typically found at the bottom of the deep end. This valve allows groundwater to enter the pool shell, equalizing the pressure and preventing damage. Open this valve *before* you begin draining. If your pool doesn’t have one, draining slowly is even more critical. Use a submersible pump to remove water, being mindful of the drainage location to avoid flooding your yard or a neighbor’s property. Never drain the pool completely unless absolutely necessary for repairs or resurfacing. Once drained, clean the pool promptly and refill it as quickly as is feasible.

What’s the best way to drain a pool partially versus completely?

The best way to partially drain a pool is using the pool’s pump and filter system to discharge water through the backwash valve (if equipped) or by using a submersible pump to lower the water level to the desired point. For a complete drain, a submersible pump is essential, usually placed in the deepest part of the pool to remove the remaining water efficiently. The key difference lies in the extent of water removal and the need for a more powerful and dedicated pump for a complete drain.

When partially draining a pool, the existing filtration system offers a convenient method. By connecting a backwash hose to the backwash port (typically found on sand or DE filters) and setting the multiport valve to the “backwash” setting, the pump will discharge water. Monitor the water level and switch off the pump once the desired level is reached. If you have a cartridge filter or need faster drainage, a submersible pump is still an excellent option for partial drains. These pumps are readily available at hardware stores and pool supply retailers. Completely draining a pool presents different considerations. Because you’re aiming to remove nearly all the water, the submersible pump should be positioned in the deepest part of the pool to ensure effective removal of the final inches of water. Be aware of the water table in your area and the pool’s construction, as completely draining some pools can cause them to “pop” or float due to hydrostatic pressure if the water table is high. In such cases, consult a pool professional before proceeding. Also, consider where the discharged water is going. Avoid draining into areas that could cause flooding or damage, adhering to local regulations regarding water disposal.

Can I drain my pool directly into the street or sewer?

Generally, draining your pool directly into the street, storm drain, or sanitary sewer is illegal and not recommended. Most municipalities have strict regulations regarding water discharge, and pool water often contains chemicals like chlorine, algaecides, and cyanuric acid that can harm the environment and potentially contaminate the water supply.

Many local ordinances prohibit this practice due to the environmental impact. The chemicals in pool water can kill aquatic life in streams and rivers that storm drains often lead to. Even if the water appears clear, it can still contain levels of chlorine or other substances harmful to the ecosystem. Moreover, a sudden large discharge of water can overwhelm the storm drain system, potentially causing localized flooding or backups. Similarly, draining into the sanitary sewer system can disrupt wastewater treatment processes, especially if the water contains high levels of chlorine. Instead of directly draining into the street or sewer, consider these alternatives: dechlorinate the pool water and drain it slowly onto your lawn or garden (ensuring it doesn’t run off onto neighboring properties), or contact a professional pool service to pump and haul away the water for proper disposal. Check with your local authorities (city hall, water department, or homeowners association) to understand the specific regulations in your area regarding pool drainage. They can provide approved methods and ensure you comply with environmental protection laws.

What safety precautions should I take when draining a pool?

Draining a pool can be hazardous if proper safety precautions aren’t taken. The primary concerns are structural damage to the pool, potential “floating” of the empty pool shell due to groundwater pressure, and electrical hazards. To mitigate these risks, always turn off all electrical power to the pool equipment, monitor the weather forecast to avoid draining during heavy rain, and ensure you understand the groundwater conditions around your pool. If you suspect high groundwater, consider hiring a professional.

Draining a pool completely removes the water that provides structural support. If the surrounding soil is saturated with water (high water table), the hydrostatic pressure can cause the empty pool shell to lift or crack. Before draining, consult with a local pool professional or conduct a groundwater test. This might involve digging a small hole near the pool to observe the water level. If water fills the hole quickly, it indicates a high water table, and you should seriously reconsider draining the pool yourself. Partial draining might be a safer option in such cases. Furthermore, be aware of the risk of entrapment, especially in older pools. Suction outlets can pose a danger if they aren’t properly disabled. Always disconnect or block the suction line at the equipment pad before draining. If you’re unsure how to do this safely, consult a pool professional. Finally, never allow children or pets near the pool while it’s being drained, and ensure the area is clearly marked as a construction zone. Remember, prevention is key to a safe pool draining process.

How long does it typically take to drain a swimming pool?

The time it takes to drain a swimming pool typically ranges from 8 to 24 hours, but it can vary significantly depending on several factors including the pool’s size, the pump’s flow rate, the diameter of the hose used, and whether you use a submersible pump or rely solely on the pool’s filter pump.

To elaborate, a larger pool, naturally, will require more time to drain than a smaller one. The flow rate of the pump is a crucial factor; a pump with a higher gallons-per-hour (GPH) rating will drain the pool much faster. Using a submersible pump designed for draining can significantly expedite the process compared to using the pool’s existing filter pump, which is not optimized for this purpose. The diameter of the hose also impacts drainage speed; a wider hose allows for a greater volume of water to flow through it at any given time. Furthermore, consider the location where you’re draining the water. Ensure the discharge point is a safe distance from your house and your neighbor’s property to avoid potential flooding or damage. Draining into a sewer line may be restricted in some areas, so checking local regulations beforehand is essential. Also, avoid draining during or immediately after heavy rainfall, as the ground may already be saturated and unable to absorb the excess water effectively.

What do I do with the pool chemicals before draining?

Before draining your pool, you need to neutralize the chemicals in the water to avoid harming the environment or damaging local sewer systems. Specifically, you must lower chlorine levels to 0 ppm and balance the pH between 7.2 and 7.8.

Chlorine is a powerful disinfectant, but high concentrations can be toxic to plant and animal life if released into the environment. Stop adding chlorine at least a week before you plan to drain the pool to allow the levels to naturally dissipate. You can use a chlorine test kit to monitor the level. If chlorine levels are still too high closer to your drain date, a chlorine neutralizer, like sodium thiosulfate, can be used to expedite the process. Follow the product’s instructions carefully to avoid over-neutralization. Proper pH balance is also important. Water that is too acidic or too alkaline can damage surfaces and harm aquatic life. Test the pH using a test kit and adjust it using pH increaser (soda ash) or pH decreaser (muriatic acid or sodium bisulfate), as needed, following label instructions for proper dosage. Ideally, wait a day after adjusting pH before draining to allow the chemicals to fully circulate and stabilize. Remember, local regulations may have specific requirements for draining pool water into the sewer system or storm drains. Always check with your municipality before draining to avoid fines or other issues.

What should I do after draining the pool before refilling?

After draining your pool, the immediate next step is to thoroughly inspect and clean the entire pool surface. This includes removing any debris, algae stains, or mineral deposits. Addressing these issues while the pool is empty is significantly easier and more effective than trying to manage them once the pool is refilled.

After draining, you’ll have the unique opportunity to tackle tasks that are difficult or impossible to do when the pool is full. Give the entire surface a good scrub. Use a pool-specific cleaner appropriate for your pool’s surface (vinyl liner, plaster, fiberglass, etc.) and follow the manufacturer’s instructions carefully. Pay special attention to areas prone to staining or algae growth, such as corners, steps, and around fittings. Now is also the time to inspect for any cracks, chips, or other damage to the pool surface. Small cracks can often be repaired with epoxy, while larger issues may require professional attention. Also inspect and clean the filter, pump, skimmer, and other pool equipment. Before refilling, it’s beneficial to lubricate any O-rings and gaskets in the plumbing system to ensure a tight seal and prevent leaks. Pay close attention to the main drain, skimmer, and return fittings. Check the condition of your pool lights and replace any bulbs or fixtures that are damaged or nearing the end of their lifespan. Replacing them now saves you from having to drain the pool again prematurely. Finally, consider having a professional pool service inspect the pool before refilling, particularly if you’ve noticed any significant damage or are unsure about any aspect of the cleaning or repair process. A professional can identify potential issues you might have missed and ensure your pool is ready for another season of enjoyment.

And that’s all there is to it! Hopefully, this guide helped you successfully drain your pool. Thanks for reading, and be sure to check back soon for more helpful tips and tricks to keep your pool sparkling and swim-ready!