Using a boat in salt & freshwater: Is it fine?


Thinking of using a boat in saltwater and freshwater and wondering whether it is OK to use a boat both in fresh and saltwater? Let’s see some effects of using a boat in fresh and saltwater to conclude that.

A boat can be used in fresh and saltwater; a saltwater boat can be used in salt and fresh water; likewise, a freshwater boat can be used in fresh and saltwater. Extra care is required while using a boat in saltwater due to more saltness than in freshwater. Other than that, the rest is the same.

There is no much of a difference between a saltwater boat and a freshwater boat. The two main differences between fresh and saltwater boats are the saltwater boats are designed well to fight against corrosion than a freshwater boat, and hulls are designed well to overcome bad weather (especially if used in salt waters like seas or oceans than in lakes or ponds).

If you are thinking of using a boat in freshwaters (like lakes, ponds, or rivers) and salt waters (like seas or oceans; not in saltwater lakes or ponds), you better be going for a saltwater boat because saltwater boats can handle rough weather in seas or oceans well than freshwater boats.

So, the main thing to consider here is if you boat in freshwater and saltwater like seas or oceans, you better be going for a saltwater boat; otherwise, if you boat in freshwater and saltwaters like lakes or ponds, a freshwater boat will accomplish your needs well.

We will now see some of the effects of using a boat in saltwater and freshwater to understand the primary differences in a detailed way.

Related post – How long can you leave a boat in the water? Check this article to know how long you can leave a boat in different waters without worrying about a hull’s growth.

Effects of using a boat in saltwater?

Saltwater will hurt your boat more than any other waters. You need to prepare your boat so much to prevent damages from salt waters. Here’s how saltwater affects boats.

Saltwater damages the metal parts on the boat by corroding and forming rust on the surface (metal) if they aren’t appropriately maintained. Saltwater is highly corrosive, and saltwater corrodes metal 5 times faster than freshwater. So saltwater affects the boat more than any other waters.

However, it is impossible to avoid corrosion altogether, but it is possible to prolong the process with the proper maintenance precautions such as washing the boat and flushing the outboard with fresh water after every ride.

The main effects of saltwater on boats are rust, nothing else, and the rest of the problems are the same as the common problems related to freshwater. Saltwater is highly corrosive, and saltwater corrodes metal 5 times faster than freshwater.

And one more thing to note is the corrosion rate depends on the amount of salt content in the water (salinity). High saline water will corrode the metals faster than less saline water. That being said, we will now see the affected parts of the boat using in saltwater, and most of them are also quite common in freshwater, but it takes more time to occur.

Check this small and quick video on the effects of using a boat in saltwater.

1. Boat hull (constructed material)

The boat hull also gets affected by saltwater. But it depends on the type of material with which the boat hull is constructed. Here are a few boat hulls that get affected by salt waters.

Fiberglass boat: Fiberglass boat can fade quickly (high chances) in saltwater. And can form scratches on the boat hull compared promptly to in freshwater. Aluminum boat: Aluminum boats will do quite well in the saltwater, but to prevent fouling, you need to use bottom paint on the hull.

Prevention tips

  1. Apply bottom paint. However, the bottom paint or anti-fouling will fade out quickly in saltwater compared to freshwater, but it gives at least some minimal protection for the boat hull to some extent.
  2. Wash the hull after every ride. If you don’t have bottom paint on the boat, then you take a hard bristle brush, and you wash the boat thoroughly after every trip to prevent any damages due to saltwater.

Washing the boat with freshwater is the best way to prevent corrosion on the metal surfaces of the boat. Clean the boat with any boat cleaner for better results. If you are boating in salt waters, then you need to clean the boat every time after taking it out of the water.

You need to be careful if you are using a freshwater boat in saltwater. Some hulls are designed to go in rough waters and for offshore boating. Although a freshwater boat can be used in salt water, you need to careful while using that in salt waters.

Related post – Using an aluminum boat in saltwater: Is it fine? Check this article to know the proper precautions to take while using an aluminum boat in saltwater.

2. Outboard or inboard or i/o motor and its parts

Outboard will be the most affected boat component due to saltwater because more than half of the outboard motor is submerged in the water. And many moving components of the outboard motor are coated with a lubricant to prevent any damages. Over time, saltwater depletes those lubricant coating and leaves the moving parts vulnerable to damage.

Many parts of the outboard motor will get affected by saltwater, such as propellers, lower units, anodes, mounting brackets, etc. You can prevent all those effects of saltwater by taking proper care of them regularly.

Prevention tips

Below are some tips for cleaning the outboard motor. The same thing applies to inboard and sterndrives as well.

  1. Generally, there will be holes at the bottom of the outboard motor, just above the propeller (and these holes may vary from motor to motor). You need to keep the air muffs over them and connect it to the water pipe (hose) and start pumping the water. There will be flush ports for some other motor so that you can connect your hose directly to it.
  2. The water will go inside the motor, and it will clean the inner walls with fresh water. After starting the process, leave it for 10 min. So, it will clean the inner walls properly. While pumping the water, don’t forget to start the outboard motor before pumping the water.
  3. It is essential to flush the outboard motor with fresh water after every use if you are using the boat in saltwater.
  4. After flushing the outboard motor, use any cleaning liquid or any boat cleaner and clean the outboard motor, then open the cowling of the outboard motor and spray lubricant (WD-40 or any other) over the moving parts.
  5. Doing all those steps (washing, cleaning the outboard, and applying lubricant over it) will prevent the metal parts from corroding and forming rust.

However, it is impossible to avoid corrosion altogether, but it is possible to prolong the process with the proper maintenance precautions after every ride.

3. Trim tabs

Trim tabs on a boat will corrode due to saltwater, such as corrosion of the rivets on hinges and relay on the hydraulic press fail due to seawater and corrosion. Sometimes actuators may leak, causing the whole hydraulic pump or electric motor to rust and stop working.

Saltwater corrodes metal 5 times faster than freshwater. So you need to take proper care of trim tabs as well (if you have one).

Prevention tips

The only way to prevent corrosion on trim tabs is by washing and cleaning the trim tabs properly after taking the boat out of the water and then applying the lube over it. So, by applying the lubricant, it won’t corrode quickly.

4. Anchor and anchor line

Boat anchors and anchor lines are other essential things for the boat, and they are made up of metal (anchors and chains), which will corrode over time. If you are using the boat, you will probably use an anchor to anchor the boat.

And anchors will be set at the bottom of the water (meaning anchors will be submerged entirely in the water), increasing the corrosion on the metal by forming rust on the metal’s surface. So, without proper care, these anchors will corrode quickly than any other parts of the boat.

And anchor lines are connected to the anchor, which will be submerged entirely in the water as well. If you are using chains, then it will corrode. Otherwise, if you are using ropes instead of chains, it will wear off quickly. So, you need to take proper care of anchor lines as well, not only the anchor.

Prevention tips

These tips are not anchor ropes; it’s for anchor chains (metal) and for the anchor.

  1. By painting the anchor and anchor line with marine paints. Generally, painting the anchors and anchor lines with marine paints will be seen on big ships, not on small ships (normal boats). However, it eventually wears off, but it offers a substantial amount of protection for some time.
  2. By galvanizing the anchor and anchor line. Galvanizing the anchor and anchor lines (coating the anchor and anchor lines with zinc) is one thing many people do to prevent corrosion. However, it eventually wears off, but it offers a substantial amount of protection for some time.

Those two are essential things to do to your anchor and anchor lines to prevent corrosion. But there is one more thing to do: washing and cleaning the anchor and anchor lines after taking them out of the water. Without washing the anchor and anchor lines, they will corrode even though if you use marine paint or galvanize them.

So, wash and clean them properly after taking them out of the water to prevent corrosion over time.

5. Bottom paint will wear off or fade out quickly

Bottom paint will fade out or wear off quickly in saltwater than in freshwater, even though if you are using a good quality anti-fouling paint. Still, the bottom paint will do a good job, acting as a barrier between the boat hull and saltwater.

But in freshwater, the paint will take some more time to fade off or wear off from the hull than in saltwater. If you are boating in saltwater, you need to use anti-fouling paint for saltwater purposes, not for freshwater purposes.

Prevention tips

To prevent (to some extent, not entirely) the bottom paint from wearing off or fading out in saltwater is washing and cleaning the boat every time after taking it out of the water. Still, it can wear off, but washing will extend the bottom paint life to some extent.

6. Electric hardware and bolts

Electronic hardware and bolts will get affected by saltwater. Make sure that all the wires are kept out of the saltwater. Bolts are also made up of metals that will corrode if exposed to saltwater for an extended period of time. Bolts will form brown color stains on the boat (see the picture above) on the surface. So, you need to clean them often to prevent that.

Prevention tips

  1. For electric hardware. Try to keep all the electric hardware at a far distance from the saltwater and use any lubricant to prevent damage. Otherwise, use marine graded electronic hardware.
  2. For Bolts. To prevent corrosion on the bolts, apply lubricant or grease regularly. Saltwater corrodes metal 5 times faster than freshwater. So, you need to be careful with all the metal parts on the boat.

Effects of using a boat in freshwater

We will now some of the effects of using a boat in freshwater.

The effects of using a boat in freshwater are almost the same as using a boat in saltwater; freshwater prolongs the whole damage process (corrosion process) than saltwater, but that’s not the case with wooden boats; freshwater damages the wooden boat more than in saltwater.

The most damages related to boats occur either due to corrosion on metals or growth on the hull (algae, barnacles, blisters, etc.). Even using a boat in freshwater causes corrosion, but it is a long process. Suppose if it takes a month to form corrosion in freshwater, it can happen with a week in saltwater.

And the hull’s growth entirely depends on the organisms present inside the water, and it has nothing to specifically with saltwater or freshwater. Proper maintenances like washing & cleaning the boat after every ride, flushing the motor after every ride will eliminate most of the problems.

Related post – What are barnacles on boats? Check this article to know the effects of barnacles on boats and their prevention as well.

Key takeaways

Both salt and freshwater will definitely hurt your boat; using a boat in saltwater damages your boat quickly than freshwater due to more saltness. To tackle that well, proper maintenance (washing & cleaning the boat and flushing the motor) is required for your boat after every ride.

If you are thinking of going in oceans or seas, then better be using a saltwater boat because these boats are well designed to support rough waters and work well to prevent corrosion. Otherwise, if you boat in inland waters (calm waters), a freshwater boat is great if you wash and flush it after every ride.

Finally, a freshwater boat is good for calm waters, and saltwater boats are good for calm and rough waters (like seas or oceans). So, if you go boating in rough waters like seas or oceans than lakes or ponds, a saltwater boat will be good than a freshwater boat.

Mahidhar

My name is Mahidhar, and I am passionate about boating. Every day I learn some new things about boats and share them here on the site.

Recent Posts