Installing piles near bodies of water: how to avoid corrosion problems?

Why is installing screw piles near bodies of water always a risk?

Building near a lake or river? On the one hand, it's beautiful, but on the other, there's a lot of hassle with the foundation. Especially when it comes to screw piles. These metal "screws" are easy to install, tighten quickly, and can withstand heavy loads. But as soon as they're in wet soil, they immediately begin to fight corrosion. Let's take a quick look at why this happens and what pitfalls await.

How does water affect screw piles?

Any metal is sensitive to moisture, and screw piles are essentially ordinary metal pipes with blades. Corrosion begins the moment the pile is screwed into the ground near a body of water. Constant contact with water and oxygen triggers an oxidation reaction; in other words, rust begins to "eat" the pile.

The main risks of screw piles near water:

·         High humidity and the presence of oxygen quickly trigger corrosion. • Groundwater with a high salt and acid content literally corrodes metal.

·         Temperature fluctuations between winter and summer accelerate the destruction of the pile's protective layer.

How is corrosion of screw piles dangerous for your foundation?

Corrosion is more than just an aesthetic issue. When a screw pile is eaten away by rust, it gradually loses thickness and strength. As a result:

·         the foundation's load-bearing capacity decreases;

·         the structure begins to deform and crack;

·         in the worst case, partial or complete structural failure can occur.

Repairing such a foundation is very expensive and difficult, so it's best to protect the piles from corrosion from the start.

Common mistakes when installing screw piles near water:

·         Piles are driven without anti-corrosion protection, relying on luck.

·         Piles with cheap coatings are used that don't last even a couple of seasons.

·         Failure to take the groundwater level into account and installing piles deeper than necessary.

·         Failure to regularly inspect piles after installation.

Step-by-step instructions: installing screw piles correctly

Now let's get down to business. If you want your screw pile foundation to last a long time and without problems, it's important to follow the installation procedures. Below are clear instructions on how to properly prepare and install piles near a body of water.

Step 1: Preparing the site and choosing an installation location

·         Determine the groundwater level. It's best to install the piles slightly above the water level, otherwise corrosion problems will occur sooner.

·         Remove the organic layer of soil (the topsoil). This is what absorbs the most moisture and damages the metal.

·         Ensure the installation location is not in a flood zone during high water.

Step 2: Treating and Protecting the Screw Piles

·         Be sure to apply an anti-corrosion coating before screwing in the piles.

·         For wet soils, epoxy or polyurethane paint is ideal.

·         Allow the coating to dry completely. If you rush the installation, you could damage the protection.

Step 3: Screwing in the pile and checking the installation quality

·         Screw the piles vertically, checking the level with a special tool.

·         The pile must be screwed in to a depth below the frost line.

·         Be careful not to damage the coating during screwing, otherwise the metal will quickly begin to rust.

Step 4: Additional waterproofing and concreting the pile cap

·         The top of the pile (the pile cap) should be additionally waterproofed with bitumen mastic or concreted.

·         After applying the waterproofing or concrete, check that there are no cracks or gaps in the coating.

Step 5: Inspection and regular inspection

·         After installation, regularly inspect the condition of the piles: assess the condition of the anti-corrosion coating every 1-2 years.

·         If you notice any damage, repair it immediately by re-treating it. Don't delay—corrosion won't wait. Next, we'll look at common mistakes when installing screw piles and provide final recommendations for a reliable foundation.

Common Mistakes When Installing Screw Piles Near Water

Mistakes when installing screw piles near water are so common that many builders consider them practically the norm. But the consequences of such mistakes quickly become apparent and costly. Review this list of common mistakes to avoid making the same mistakes yourself:

• Skimping on pile coating:

Cheap paint or no coating at all is the main enemy of your foundation. Piles begin to rust immediately and quickly lose their load-bearing capacity.

• Miscalculating the installation depth:

Piles should be screwed in below the frost line and above the groundwater level. If miscalculated, the piles will begin to move and rust prematurely.

• Using piles with damaged coating:

Even minor scratches in the coating during transportation or installation become a gateway for rust. • Lack of pile cap waterproofing:

Water entering the pile from above gradually erodes it from the inside. Simple waterproofing or concreting of the pile cap solves this problem.

• Lack of post-installation monitoring:

Piles near water need to be inspected regularly. If this is not done, a small problem quickly escalates into a major one, and repairs can become a real disaster.