Spring Inspection of Your Dock – How to Prepare It for Summer
When the ice melts and the ground thaws, the season begins for everyone with a dock. Before launching your boat and setting up the swim ladder, it’s time for the most important routine of the year: a thorough spring inspection of your dock. Winter takes a heavy toll on marine structures. Ice, frost, and storms take their toll on wood, concrete, and steel alike. A thorough inspection now saves both money and headaches down the road, and can be the difference between a trouble-free summer and a sudden dock collapse in the middle of July.
Here, we’ll go over what to look for, the most common types of damage after a Swedish winter, and when it’s wise to call in professional help.
When should you do your spring inspection?
The best time is as soon as the ice has melted and the water has started to clear up. This is usually sometime between late April and mid-May, depending on where in the country you are. Conduct the inspection before you start using the dock regularly, and preferably before you set out buoys or begin any renovation projects. That way, you’ll have plenty of time to order materials and book contractors or divers well in advance of peak season.
A spring inspection doesn’t have to take long if the dock is in good condition, but be sure to set aside a couple of hours for a thorough check and take photos so you have something to compare with next year.
Above-water inspection — here’s what to look for
Start at the top and work your way systematically across the entire structure.
Deck and dock planks: Check if any planks are loose, cracked, or slippery. Moss, algae, and black deposits should be brushed off before the surface dries and becomes slippery. Gently tap any suspicious planks; a dull sound may indicate rot in the wood.
Screws, nails, and hardware: Saltwater and frost heave can loosen fasteners. Tighten anything that’s loose and replace rusty screws with acid-resistant ones. Be especially thorough around shore fastenings and at the transitions between the dock and the shore.
Railings and ladders: Safety features are the first things that must be in working order. Check that the swim ladder and any railings are securely fastened and have not been deformed by the movement of the ice. A loose ladder can be directly life-threatening.
Floating docks and pontoons: Listen for sounds that indicate water in the pontoons and check that chains, anchors, and moorings are intact. Damaged pontoons must be replaced immediately; a pontoon taking on water can pull the entire dock out of position in a matter of days.
Shore connections and access ramps: This is where the biggest problems often arise after a winter with significant changes in water levels. Check that the gangway is properly positioned and has not been lifted by ice or high water.
What’s happening underwater?
This is where most people miss important signs. What you can’t see on the surface may be serious damage further down, and a dock with invisible damage below the waterline can collapse without warning when the load increases.
Things to check below the waterline:
Piles and posts: Are they still vertical? Has the ice pushed or pulled them out of position?
Anchors and chains: Worn links, rust, and improper tension are common after winter.
Concrete and stone caissons: Cracks, washouts, and settlement occur over time and worsen rapidly if left unaddressed.
Erosion around the foundation: Winter water and currents often erode the bottom near the pilings, making the dock unstable.
If you’re able to snorkel or lower an underwater camera yourself, do so. For larger or older docks, especially those with piles, caissons, or concrete structures, we recommend a professional underwater inspection by a certified diver. It’s a minor intervention that can save the entire structure.
Common Damage After a Swedish Winter
The Swedish winter is hard on docks. These are the recurring problems we encounter in our projects:
Ice damage to piles and anchors.
When ice forms and then shifts as temperatures fluctuate, it can lift entire piles out of the bottom. This is particularly common in lakes with large variations in water level. (We’ve written more about how to build to withstand this in our post “Jetties That Can Withstand Ice.”)
Frost damage in concrete.
Water that seeps into cracks freezes, expands, and widens the damage year after year.
Rot and moisture in wood. Especially at shore attachments, under the jetty deck, and around fastenings where water collects.
Loose or missing fasteners.
Screws and bolts that give way after several years of stress.
Sunk pontoons. Leaky pontoons that have slowly filled with water over the winter.
When should you call in a construction diver?
You can perform much of the spring inspection yourself, but in certain situations, it’s the right decision to call in a professional. Contact a structural diver if you notice any of the following:
- The dock has visibly shifted since last season
- Piles or posts are leaning or appear loose
- Cracks or damage in the concrete foundation
- The dock is more than 15 years old and has not been inspected underwater
- You’re planning to renovate the dock and need a basis for determining what work needs to be done
A professional inspection provides you with documentation of the dock’s condition, which is valuable for insurance claims, property sales, and planning future maintenance.
Maintenance and Small Jobs You Can Do Yourself
Finish up your spring check with a few simple maintenance steps that will significantly extend the life of your dock:
Oil or treat the wooden deck after it has dried thoroughly. Use an oil designed for marine environments.
Wash away algae with a mild cleaner and a stiff brush, avoid using a pressure washer directly on older boards.
Lubricate hinges, chains, and lockable fasteners with rust-preventive oil.
Reinstall ladders, fenders, and other components that were removed over the winter.
Summary—Your Spring Checkup at a Glance
A thorough spring check is all about staying ahead of the season’s stresses. Inspect the top, check what’s happening underwater, document any damage, and fix the simple issues yourself. For anything out of sight or beyond what you can handle without equipment, it’s better to call in a diver now than to be left with a collapsed dock in July.
Do you need help with inspection, renovation, or other marine work on your dock? Contact us at Deep Ocean Solutions, and we’ll help you get your dock ready for summer.