Pool Overflowing From Rain? What to Do & Prevent

Pool Overflowing From Rain

Photo: thepoolbutler.net

Heavy and consistent rainfall can drastically increase the level of water in your pool, in just a short period.

After the rain has leveled out, it may be necessary to remove excess overflow water from your in-ground pool to prevent the many challenges associated with this occurrence.

If overflow goes unchecked, it can cause imbalanced pool chemistry, introduce contaminants in the pool, or damage pool equipment. Here’s more about pool overflowing and how to fix it.

Pool Overflowing Problems

Too Much Water in Pool: Having excess water in the pool can have many undesirable outcomes, including increasing the likelihood of contamination from planters, and even deck area flooding.

Too much water in the pool can make for a very poor swimming experience. If you’re already accustomed to the standard levels, anything more may distort the overall experience.

Imbalanced Pool Chemistry: A heavy rainstorm can fill the bottom of your pool with sticks, dust, pollen, algae spores, and leaves, all of which promote algae growth.

Unchecked algae growth can cause imbalanced pool chemistry. The persistent chemical imbalance in your pool can cause damage that may be hard to reverse when you take action.

Contaminants in the Pool: Surface run-off can introduce contaminants into the pool. A few additional inches of rain falling into your pool can trigger flooding.

Surrounding lawns, concrete pool decks, and planters can bring soil and mulch into the water, and risk elevating phosphate levels, which are associated with algae and cloudy water.

Damaged Pool Equipment: Another risk introduced by overflowing is the potential flooding of essential pool equipment such as filters and pumps, which can be expensive to replace or repair.

Even if the overflow does not cause the equipment to break down, it can impede their optimal function, which exposes the pool to other potential issues such as cloudy or green water, common problems associated with poor pump/filter performance.

What to Do if Your Pool is Overflowing 

What to Do if Your Pool is Overflowing

Photo: ultimatepools.us

1. Lower Water from Your Pool

Siphon It

You can drain water easily and cost-effectively using a simple garden hose for siphoning. This process is incredibly easy even for a beginner.

Simply insert one end of the hose into the pool, then place the other end on a lower elevation so that the force of gravity powers and sustains the water flow.

To get the water flow started, you will need to create negative pressure. You can achieve this by rapidly dropping the free end, and if that proves challenging, simply such on it to create suction.

A point of caution, however, is that the second option may prove distasteful. You can check out simple alternative siphoning tips, such as the one offered by this YouTube video.

Use Your Pump Drain Spigot

Some pool pumps feature drainage spigots. If you have such a pump, the spigot will likely be positioned between the pump and the cartridge filter.

If such a component exists in your pump setup, simply connect a hose to the spigot, open the component, then let the pump action handle the rest.

When the ideal water level is achieved, simply switch off the pump and disconnect the hose.

Use a Submersible Pump

This type of pump is designed to work underwater. You may already own a submersible pump, or have encountered it at some point especially if you’ve ever had to drain your pool.

Also known as a pool cover pump, it is a powerful unit that will reliably drain waster from pools and spas.

You simply hook a drainpipe to the pump, lower the pump into the pool slowly, allowing it to sink to the bottom, then plug it into a power supply to commence the draining process.

Proceed to drain the water until it reaches the ideal level in the pool, then you can switch off and extract the pump.

This option is especially recommended if you don’t have access to a multi-port valve or drainage spigot.

Call a Professional

If you want to get the pool drainage process right and with the best possible results, you can hire a professional to help lower the water level.

A professional will most likely know the ideal pool draining schedule, which is typically 3 – 5 years. Also, if there are some draining steps that you are still not clear on, a professional will know exactly what to do.

It’s worth noting, however, that for professional services, you will probably end up spending a considerable amount of money, but this is worth the desired outcomes are guaranteed.

2. Test Pool Water and Shock

Regular pool testing is recommended to ensure the right chemical balance is maintained at all times. It was earlier established that chemical imbalances can cause overflows.

You can test your pool for many things including chlorine, chloramines (combined chlorine molecules), and algae.

If you establish the levels of chloramines, algae and contaminants are high, then you can shock your pool. Shocking is the addition of a granular oxidizer into the pool water.

This oxidizer is typically a powdered form of chlorine, which can raise the water’s free chlorine levels high enough for the destruction of common contaminants.

Pool shock can also help to reactivate bromide ions, which are effective in destroying offending contaminants. All these great shock benefits can help lower pool water levels.

Tips to Prevent Your Pool from Overflowing

Tips to Prevent Your Pool from Overflowing

Photo: abc.net.au

Monitor water inflow: A simple way of preventing pool overflow is to monitor the amount of water getting into the pool.

Pools have fill lines that can indicate, clearly, the exact water levels, which help to mitigate overflow issues flows originating from heavy rains or water displacement.

Install a pool overflow drainage: This is, arguably, the best way to prevent pool overflow. Typically, this system is installed around the pool’s lip/rim.

The system is great for an overflow that is impossible to avoid, such as that caused by heavy rains. It will quickly counter any potential overflows and even protect the pool from damage.


Pool overflow from rain can present significant challenges that either ruin your swimming experience, distort the pool’s stable conditions, or even render it unusable.

Unfortunately, it is hard to control rainwater and its capacity to cause pool overflow.

When this happens, you can implement some reliable strategies such as siphoning, using a pump spigot, using a submersible pump, or seeking a professional service to remove the overflow.