Maintaining a swimming pool requires ongoing commitment, knowledge, and the right approach to ensure safety, longevity, and enjoyment. Most pool owners will face a critical decision at some point: Is it better to completely drain the pool or simply clean it thoroughly? While the answer may seem straightforward, several factors—like pool type, water condition, maintenance history, and environmental concerns—play a significant role in making the best decision.
This article explores the pros and cons of draining versus cleaning a swimming pool. We’ll discuss the optimal situations for both, the implications of each process, and provide actionable insights to help pool owners make informed decisions.
Understanding the Basics: What Do Draining and Cleaning Mean in Pool Maintenance?
Before comparing draining and cleaning, it’s essential to define each process and understand where they fit in the broader scope of pool maintenance.
Cleaning a Pool
Cleaning a pool involves regular maintenance activities done without draining the water. This includes:
- Skimming the surface for debris
- Vacuuming the floor and walls
- Brushing tile lines and pool surfaces
- Checking and balancing chemical levels
- Running filtration systems for optimal water turnover
Routine cleaning is a fundamental part of pool ownership and helps prevent the buildup of algae, bacteria, and contaminants. It typically requires daily or weekly upkeep, depending on usage and environmental conditions.
Draining a Pool
Draining a pool means completely emptying it to perform deep maintenance or address significant water quality issues. This is a more intensive action that’s often a last resort, reserved for repairs, major restorations, or when water conditions become unsafe or irreversibly compromised.
Due to the risk of pool structure damage—especially in concrete pools that rely on hydraulic pressure—draining must be done carefully and with professional guidance in many cases.
When Should You Clean Instead of Drain?
The general rule of thumb is: clean when possible, drain only when necessary. Here’s a list of situations where regular or deep cleaning is sufficient:
Algae Growth (Mild to Moderate)
Green or yellow algae can typically be managed through a thorough cleaning regimen including:
- Brushing all infested surfaces
- Shocking the pool with chlorine
- Algaecide application
- Extended filter operation
Provided the structural integrity of the pool and equipment are intact, cleaning the water and surrounding areas should clear most algae concerns effectively.
Unbalanced Water Chemistry
Common water issues, like high or low pH, improper alkalinity, or excessive phosphate levels, can be corrected using chemical treatments. Testing water regularly and adjusting chemistry accordingly is key.
Daily Maintenance
Keeping a pool in good condition primarily revolves around daily or weekly cleaning:
- Removing leaves and insects
- Vacuuming to remove settled particles
- Monitoring and adjusting sanitization levels
- Backwashing filters when necessary
Routine cleaning helps preserve chemical balance and prevents heavier issues.
When Should You Consider Draining Your Pool?
There are definite scenarios where partial or complete draining becomes the best option:
Severe Algae Infestation or Contamination
If your water has turned black or appears beyond repair despite chemical treatment, draining may become necessary. This is common in neglected or improperly operated pools.
High Total Dissolved Solids (TDS) or Staining
Over time, the accumulation of dissolved solids from added chemicals, sweat, sunscreen, and other sources makes the water “heavy” and resistant to balancing. High TDS combined with staining can warrant drainage.
Warning: Draining a concrete pool without proper preparation risks structural damage like lifting or cracking due to underground water pressure.
Structural Repairs or Surface Maintenance
If your pool requires resurfacing of the plaster, tile replacement, or crack repairs, it must be drained to allow work crews to operate effectively and apply materials correctly.
Eco Tip:
Always check local regulations before draining—it may require municipal permits due to environmental concerns from chlorine or other chemicals.
Pros and Cons of Pool Draining
Is draining ever the answer? In short, yes—but it comes with tradeoffs. Here are the most common benefits and drawbacks.
| Pros of Draining | Cons of Draining |
|---|---|
| Deep cleaning possible: Nooks and crannies can be properly cleaned, resurfaced, and disinfected. | Water waste: Draining a typical 15,000–20,000-gallon pool represents significant environmental and utility cost. |
| Structural maintenance: Repairs, tiling, or painting require draining for safe and proper application. | Time and expense: Refilling and rebalancing chemicals takes time and money, plus pool is out of commission for days. |
| Elimination of persistent issues: Contaminants, discoloration, and algae buildup beyond chemical treatment can only be resolved by emptying the pool. | Risks concrete pools: Vinyl and fiberglass pools are less affected, but concrete pools risk damage from pressure changes if drained improperly. |
Pros and Cons of Intensive Pool Cleaning Without Draining
Cleaning without draining is typically preferred due to its efficiency, eco-friendliness, and cost-effectiveness.
| Pros of Intensive Cleaning | Cons of Intensive Cleaning |
|---|---|
| Cost-effective: Does not require draining, refilling, or water treatment chemicals at scale. | Time-consuming: Severe algae or debris may require multiple cleaning sessions and extended filtration. |
| Little disruption: Pool can usually remain useable during cleaning (outside of initial shock periods). | Limited effectiveness: Heavily stained or chemically damaged pools may not fully recover without draining. |
| More environmentally responsible: No wasteful water disposal, reducing your pool’s carbon footprint. | Risk of recurring problems: If the root cause isn’t addressed, the same algae or chemical imbalance could return. |
Pool Type Matters: How Pool Construction Influences the Draining Decision
Not all pools respond the same way to draining. The type of pool you own significantly impacts whether it should be drained or not.
Concrete (Gunite or Shotcrete)
Concrete pools rely on water inside the shell for stability. If drained improperly and without sufficient countermeasures (like hydrostatic plugs), the groundwater beneath the pool can force the shell upward—leading to cracks, shifting, or even lifting the pool out of the ground.
Fiberglass
Fiberglass pools are rigid but can usually be safely drained due to their lightweight yet flexible structure. Still, always check manufacturer recommendations.
Vinyl Liner Pools
These are the most suitable for draining. Some repairs require temporary emptying, but care should be taken to avoid damaging the liner when water is absent.
Draining a Pool the Right Way: A Step-by-Step Guide
If you determine that draining is the most logical option, follow these key steps to avoid problems:
1. Test Water Condition
Determine if draining will resolve the issue or if chemical corrections may still work.
2. Check Local Bylaws and Water Use Regulations
Some regions prohibit large-scale water disposal due to drought or environmental rules.
3. Prepare for the Draining Process
Turn off all pool equipment and ensure the drainage hose meets recommended outlets, such as municipal sewer or storm drains.
4. Slow, Controlled Draining
Especially for concrete pools, maintain balance with hydrostatic plugs or staged water removal, ideally under professional supervision.
5. Perform Needed Repairs Immediately
While the pool is empty, conduct necessary cleaning, repairs, or painting promptly to prevent weather-related degradation or debris accumulation.
6. Refill and Rebalance Water
Once maintenance is complete, refill the pool carefully, then conduct extensive water chemistry balancing.
Cleaning Your Pool Without Draining: Best Practices
If you opt to keep the water, follow these best practices:
Regular Skimming and Debris Removal
Use a skimmer net daily to remove leaves, grass, and floating insects. This prevents organic load from increasing chemical consumption.
Brushing and Vacuuming Surfaces
Brush walls and floors weekly, especially if you notice staining, scale buildup, or slime growth. Vacuum to eliminate settled dirt and debris.
Testing Water Chemistry
Use a digital tester or test strips at least twice a week to ensure balanced pH, alkalinity, and chlorine levels.
Proper Chemical Dosing
Overdosing or under-dosing pool chemicals can lead to corrosion, etching of surfaces, or unsafe swimming conditions. Always follow manufacturers’ instructions and consult professionals if unsure.
Shocking for Algae and Contaminants
If algae growth or cloudy water occurs, perform a chlorine shock—high levels of chlorine used to kill bacteria and algae—to restore clarity and sanitization.
Environmental Impact: How Cleaning vs. Draining Affects Sustainability
The choice between cleaning and draining also plays into sustainability and environmental considerations.
Water Conservation
Today, water conservation is a key concern in many regions, especially in drought-prone areas like California or Arizona. Draining a pool consumes thousands of gallons of water, while effective cleaning and filtration minimize waste.
Chemical Disposal
Pools use chlorine, algaecides, and pH adjusters. These chemicals often require neutralization or EPA-compliant disposal if the water is dumped. Cleaning without draining circulates chemical use more responsibly.
Carbon Footprint of Pool Operations
Refilling a pool demands fresh water purification and transportation, both energy-intensive. Regular maintenance reduces reliance on new resources and preserves energy.
Tip: Replacing older pool pumps and filters with Energy Star rated models can further reduce environmental strain, regardless of cleaning or draining.
Cost Comparisons: Draining vs. Cleaning Your Pool
Pool maintenance decisions often come down to cost, especially for homeowners managing budgets.
Cost to Drain a Pool
- Pumping and Disposal: $100–$500 depending on size and local rates
- Repairs: $500–$2,000 for resurfacing, plumbing, or tiling
- Refilling: $500–$1,500 based on water costs and pool size
- Chemical Rebalancing: $100–$300 after refill
Cost to Clean a Pool
- Basic Skim and Brushing: Free (DIY) or $100–$200 (professional service)
- Test Strip or Kit: $50–$150 annually
- Shocking and Algaecide: $50–$100
- Professional Weekly Cleaning: $75–$150 per visit, or $300–$500 monthly
Clearly, cleaning consistently and correctly is far more cost-efficient than the intermittent need for draining.
Expert Advice: When in Doubt, Consult a Licensed Pool Technician
Whether to drain or clean your pool might appear straightforward on paper, but real-world variables—including water hardness, temperature, pump condition, and pool age—can complicate matters.
Licensed pool technicians can:
- Test for TDS, calcium hardness, and cyanuric acid
- Suggest cost-effective treatments for algae or stains
- Advise on whether draining is truly necessary, depending on your situation
Experts can often bring a neglected or imbalanced pool back to life without costly drain-and-refill measures, especially when problems are identified early.
Final Verdict: Choose Cleaning First, Draining with Caution
In nearly all routine maintenance and moderate contamination situations, the best answer is to clean your pool rather than drain it. Cleaning is cost-effective, eco-friendly, and ensures that your investment remains safe and structurally sound.
However, in cases of serious structural issues, unrecoverable water chemistry, or when major maintenance is required, draining the pool becomes the most viable—and in some cases, the only—solution.
Remember:
- Pools are built to hold water; their stability often depends on it.
- Concreting pools are especially vulnerable to improper draining.
Always evaluate your unique situation. When unsure, consult with a licensed professional and use data-driven tests to steer your decision. Prioritize maintenance, and you may never need to totally drain your pool for years.
Is it better to drain a pool for cleaning or just clean it while full?
Draining a pool solely for routine cleaning is generally not recommended unless there are specific issues like high total dissolved solids (TDS), persistent algae, or necessary repairs. In most cases, regular maintenance such as skimming, vacuuming, and brushing, along with proper chemical balance, is sufficient to keep a pool clean and healthy. Draining a pool can be costly, time-consuming, and potentially damaging to the pool structure, especially in in-ground pools where hydrostatic pressure can cause lifting or cracking.
However, there are situations where draining becomes the more effective or even necessary option. For example, if the water has become heavily contaminated or if the chemical balance is beyond correction without a full water replacement, draining may be the best course of action. Additionally, when resurfacing or performing major repairs, draining is a required step. The decision should be based on the specific condition of the pool and the advice of a professional pool technician.
What are the risks of draining a pool?
Draining a swimming pool improperly poses several risks, particularly to the structural integrity of in-ground pools. Without water to balance external pressure from groundwater, the pool can “pop out” of the ground, leading to severe and costly damage. This is especially common in areas with high water tables or after heavy rains. Fiberglass and vinyl-lined pools are particularly vulnerable to this kind of upheaval.
Another concern is damage to pool surfaces and equipment. Draining an older pool with a plaster finish can lead to drying and cracking, while leaving equipment disconnected for long periods can void warranties or cause mechanical failure when restarted. There’s also the environmental impact of disposing of large amounts of chemically treated water. For these reasons, it’s essential to follow best practices and consult a professional before deciding to drain.
How often should I clean my pool without draining it?
Routine pool maintenance should be performed weekly to keep the water clean and chemically balanced. This includes skimming debris from the surface, brushing the walls and floor, vacuuming the pool, and checking filter operation. Water chemistry should be tested at least twice a week, especially during periods of heavy use or hot weather, to maintain proper pH, chlorine, alkalinity, and calcium hardness levels.
A more thorough cleaning, including backwashing or cleaning the filter, checking all equipment for wear or damage, and spot-treating for stains or algae, should be done monthly. If problems arise such as discoloration, cloudiness, or difficulty maintaining chemical balance, it may indicate a need for deeper intervention. In such cases, rather than draining immediately, consider adjusting your cleaning routine or consulting with a pool expert for targeted solutions.
When should I consider draining my pool?
There are specific scenarios where draining your pool becomes the most practical and effective solution. Persistent water clarity problems that don’t improve with treatments, excessively high TDS levels that interfere with chemical efficiency, or major infestations of algae resistant to conventional treatments can all warrant complete draining. Draining is also necessary when resurfacing the pool, repairing structural components, or when preparing for winterization in some climates.
Additionally, if the pool water becomes contaminated with high levels of non-filterable debris or chemicals that cannot be corrected through partial draining or dilution, a full drain might be essential. It’s also important to consider local water regulations, as some areas restrict pool draining due to water conservation efforts. Always contact a pool professional before making the decision to drain, especially for in-ground pools, to ensure safety and minimize damage risk.
Can draining a pool damage the liner or surface?
Yes, draining a pool improperly can cause significant damage to the liner or surface, especially in vinyl-lined or fiberglass pools. When a pool is drained, the liner or shell is no longer stretched by the weight of the water, which can allow it to shrink, crack, or warp. In vinyl-lined pools, wrinkles or tears may develop when the pool is refilled, because the liner may not conform to the original shape if it dries out completely.
For concrete or plaster pools, draining doesn’t typically cause permanent damage to the surface unless the water was low for an extended period, leading to cracks or scaling from lack of moisture. If there is any doubt about the material’s ability to withstand drying, it’s safer to keep the pool partially filled or consult a professional. Taking preventive measures such as misting surfaces to avoid drying or keeping hydrostatic relief valves open can help minimize potential damage.
How can I maintain my pool if I choose not to drain it?
If you choose not to drain your pool, maintaining clean and balanced water is key. Regular skimming, vacuuming, and brushing help prevent debris buildup and algae growth. Filter systems should be operated according to manufacturer recommendations, typically for at least 8–12 hours per day, depending on usage and season. Routine chemical testing and adjustments ensure that chlorine, pH, and alkalinity remain within ideal ranges to prevent scaling, corrosion, and health hazards.
Additionally, using algaecides and clarifiers can help maintain water clarity and prevent problems before they become severe. It’s also important to inspect and maintain pool equipment like pumps, heaters, and automatic cleaners to ensure optimal performance. Weekly inspections and scheduled professional services can help identify early issues, like circulation problems or chemical imbalances, and prevent the need for more extreme solutions like draining the pool.
Are there eco-friendly alternatives to draining my pool?
Many eco-friendly alternatives exist that reduce or eliminate the need to fully drain a pool. Partial draining and dilution can help manage TDS levels and correct chemical imbalances without wasting the entire volume of water. Using phosphate removers, enzyme-based cleaners, and natural algaecides can help maintain clean water while reducing the reliance on harsh chemicals that can make water harder to dispose of responsibly.
Additionally, maintaining a solid filtration and sanitation schedule helps reduce water waste by prolonging the need for replacement. Recirculating or treating water on-site through cartridge or sand filters with extended backwashing cycles can also help preserve water quality. Some areas have pool water recycling services that treat and repurpose pool water, which is an excellent alternative to complete drainage if your pool does require a large water change. Always check local water conservation programs for best practices and available support.