Will Pool Water Kill Grass? The Effects of Chlorine and Salt on Your Lawn

Will Pool Water Kill Grass

Swimming pools only look good if the yard they’re in is also aesthetically pleasing. They complete each other; a swimming pool alone would look barren. That said, some pool owners are worried when grass and plants are too close to the pool in fear of salt or chlorine damaging them.

Thankfully, if you prepare properly, you can ensure the pool water – be it chlorine or salt – won’t kill your grass. Generally speaking, a splash here and there won’t kill your grass because the chlorine and salt in pool water are heavily diluted. What you should be worried about is draining your pool or spilling undiluted chlorine onto your grass – this can cause irreparable damage to the soil.

If you notice patches of grass are turning yellow and dying, then those are perhaps areas where chlorinated water keeps splashing onto, or a large concentration of chlorine somehow was spilled there.

In this article, we will discuss the impact that chlorine and saltwater pools have on nearby grass and plants, as well as how you can safely manage your pool so that you don’t accidentally kill your grass.

What effect does chlorine have on your lawn?

All chlorine in your pool is already diluted. This means that the concentration of chlorine in the pool is low. Undiluted chlorine is highly concentrated chlorine that has not yet been added into the pool, such as when it’s still in its tablet, powder, or liquid form. If you spill that on your lawn, then the grass and soil it lands on can be permanently damaged.

Since the pool water dilutes the chlorine, having a little bit splash out here and there should not be harmful to your grass. However, even diluted chlorine, in large enough concentrations, can kill your grass.

An example of this is if you were to drain your pool, exposing your lawn to a large amount of chlorine. Before draining your pool, you must dilute it with even more water so that the chlorine becomes even less potent.

Chlorine can kill your grass because it dissolves the minerals present and even alters the pH level of grass. Chlorine can cause grass to become dry and brittle, and kill grass within 3 to 5 days if there is enough chlorine.

If you accidentally spill a large amount of chlorine onto your grass, there may still be time to save it. Turn on your sprinkler system or manually hose down your lawn to dilute the chlorine. Make sure you don’t overfill your lawn with water.

What effect does salt water have on your lawn?

Not everyone has a chlorine pool; salt water pools are becoming quite popular too. However, I think the negative effects that salt has on grass are a lot more ubiquitous than knowledge about chlorine’s negative effects.

If you live near a beach, have you ever wondered why there isn’t grass to be found near it? That’s because salt and grass are not great friends.

Specifically, salt can stifle root growth and prevent nutrients and water from being absorbed by your grass. Salt can also linger on your grass and in the soil for a long time until it is washed away by fresh water.

Again, occasional splashes of salt water onto your pool is not much of an issue. Like chlorine, the concentration of salt in a salt water pool is low because of how diluted it is. And just like chlorine, the big problem is when you drain your pool.

The solution is also the same: dilute the pool with more water before draining, and turn on your sprinkler system or manually spray your grass with fresh water to ensure the salt is being washed off.

When does pool water kill your grass?

As mentioned, draining your pool water can kill your grass because it allows the water to infiltrate your soil.

With chlorine pools, the chlorine concentration is typically anywhere from 1.0 to 3.0 ppm. Prior to draining the pool you need to lower the concentration down to 0.1 ppm by diluting it with more freshwater or letting the sun evaporate the chlorine.

You should use a water testing kit to ensure the chlorine concentration has reached this level before draining your pool.

With salt water, many locations let you drain it on your own property. The issue is that you don’t want the salt to gather in one area which can damage the soil. The recommendation is to drain into a sanitary sewer or clean-out line.

Another risk of draining your pool water on your lawn is that you risk flooding the grass, drowning the roots and attracting mosquitos. Chlorine or no, a large amount of water hitting your lawn can kill it.

To avoid flooding, you should drain your pools in intervals. While this significantly lengthens the process, spreading it out over multiple days, at least you’re not going to kill your lawn while doing it. Besides, a pool drainage is only necessary every few years, so it’s not like this is going to be a weekly occurrence. Be patient.

Can you reuse pool water to water your lawn?

Draining your pool seems like such a huge waste of thousands of gallons of water. Is there any way to use some of that water to at least water your lawn? If the lawn can handle the occasional splash from the pool, then maybe you can use some of the water for a better purpose?

The answer is both yes and no. No, you cannot just take your chlorinated pool water and water your plants with it. There is a proper way of doing this. As mentioned, you should de-chlorinate your pool so that the concentration is much lower.

Since pools rarely need to be drained, the opportunity for pool water to be used for your lawn is rare. However, backwashing occurs much more often. And backwashing produces around 75 gallons of water that can be used to water salt-tolerant plants.

Why is grass near my pool dying?

Even though the occasional splash shouldn’t kill grass, you may notice that some of the grass by the pool has started turning yellow and dying anyways.

If this is happening, the most likely culprit is that your pool is over-chlorinated. In other words, there is a high enough concentration of chlorine in your pool water such that even the occasional splash is killing your grass.

Too much chlorine in the pool is bad for your health. It can cause rashes, coughing, eye and skin irritation, dry hair, respiratory issues such as asthma, and nose and throat pain.

You must monitor your chlorine levels using a water testing kit at least a few times a week so that you can balance the chlorine, pH, and other chemicals. Maintaining proper chlorine levels is necessary not just for nearby plants, but more importantly, the people swimming in the pool.