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CHAPTER 4:

FIXED DOCKS

The Benefits and Best Conditions

Standing on legs like an oversized table, the fixed dock provides sturdy and stable access from ship to shore. Fixed means that it is not meant to move or to float on the water; the fixed dock remains stationary. A fixed dock may be a permanent structure or one that is made portable in severely cold climates, removed before winter ice takes effect. Its legs, using standard wooden posts from a lumber store or galvanized steel pipe, are usually set into the riverbed, lake bed, or seabed for dependable boat anchorage. For lighter service applications, depending on the environment, there are options that simply stand the fixed dock’s legs on feet or skids. Following my description of suitable environments for fixed docks, I will provide you, in detail, four of the best proven DIY methods for building them that won’t break your wallet or your back.

For seven years, I lived on Long Lake in Naples, Maine, where my fixed dock faced north with several miles of open water between it and Mt. Washington. Some days, it was a peaceful paradise. On other days, wind swept down from the nearby mountain to deliver an onslaught of waves. Relentless were the rollers, 2 to 3 feet (60.96 to 91.44 centimeters) high with whitecaps that would crest and crash over the rocky shore. Intrepidly, however, the fixed dock stood firmly on its legs in the middle of it all. At the right height, it provided the most solid and dependable walking surface, regardless of the ominous turbulence below. When a wave rises under a fixed dock—provided the decking is above the largest wave—there is practically no surface area significant for the wave to lift against, leaving the dock and it occupants unscathed. On fair days, the lake buzzed with boats zipping around and cutting up the water. Nevertheless, with all the chop, anyone could sit out there and read or sunbathe without getting jostled. Properly built, the fixed dock should not shake or sway when walked on. There should be minimal motion if it experiences a normal bump by a boat. For anyone physically challenged or with poor balance, the fixed dock (in the right environment) is what I would recommend. For the best results, consider the following conditions.

A well-built fixed dock stands firm and ready to receive its vessels.

Pounding white-capped waves roll relentlessly under a fixed dock that remains unmoved and unscathed at its safe height above the water.

The Body of Water

A fixed dock could be put into water that is either calm or choppy, but it works best where the water level doesn’t fluctuate greatly. Near my home in Maine, where northern climates require most docks to be portable and to be removed before winter ice sets in. Not far away is Sebago Lake, where fixed docks are most popular because of the chop from wind and heavy boat traffic. Floating docks often don’t stand up well on that lake unless they are on a protected shoreline. As with the dock I had on Long Lake, fixed docks on Sebago aren’t affected by waves provided they are at a safe height above the maximum wave. The challenge there is that the water drops several feet (meters) from the mean water level between July and August, leaving folks to jump down from the dock into the boat by September. Another challenge they face is a propensity for the water level on Sebago to rise significantly from spring rains after the dock has been set for the season. This is a potential disaster for the portable dock should waves pound against its underside. My advice to anyone on a lake like Sebago has been to hold off on installing their portable fixed dock until spring rains have passed. As for the water level dropping, I recommend an adjustable fixed dock that can be lowered on its legs later in the summer.

Rivers that swell suddenly and drastically or bodies of water fed by those rivers are not usually a good place for a DIY fixed dock, nor are tidal waters in latitudes where daily levels fluctuate more than a couple feet (about 10 decimeters). In either of these situations, the DIY fixed dock will provide access over the shallows until it can transition to a floating dock in deeper water. This dock describes what I’ve classified as “fixed to floating,” which I will help you with in this book.

Exposure to Waves and Current

This exposure should not be greater than what makes practical sense. When considering the scale of a fixed dock suitable for a DIYer to build and install, be sure it matches the scale of the exposure. I’ve known DIYers to install a dock where the body of water was so big that the amount of wind and the size waves proved to be a mismatch for the dock. If you’re unfamiliar with the body of water, I recommend looking around the neighborhood. On a large body that has a ravaged shoreline where you don’t see any docks, heed the warning sign. If there are other fixed docks nearby that have the same exposure, chances are your dock should look similar in scale to those. Look at the ones that seem to be weathering well and the ones that aren’t, taking note of what appears to be working well from what doesn’t. Ask the neighbors about the history of weather, including winds, floods, and droughts, to give yourself a better idea of what your dock will be up against. If it is a sandy beach that gets pounded by wind and waves, expect lots of sand to move around the legs. The same thing can happen where there is a sweeping current. The legs of the fixed dock in these environments will need to be set deep enough into the bed to prevent undermining.

A sandy lake bed makes a firm base for a fixed dock.

An “L” or “T” platform at the end of a fixed dock adds convenient usable space while adding stability in deep water.

The Bottom

The floor of the seabed, lake bed, or riverbed where the fixed dock will stand should be firm and made of sand, gravel, clay, or stabilized rock. Putting a fixed dock on loose rock such as cobble or submerged rock piles could cause shifting under the legs, requiring seemingly constant adjustments to keep level. Extremely soft ground, such as detritus and silt (where you’d sink to your shins), will also prove challenging to keep a fixed dock level upon if there isn’t some harder material, such as gravel or clay, beneath the muck.

In this case, the legs need to extend through the soft matter until seated in something firm below. In northern climates where docks need to be removed, I wouldn’t use a fixed dock if solid ground couldn’t be found less than 6 inches (1.52 decimeters) beneath the muck. Even with mud pads or feet to support the legs, the portable dock will be a bear to remove in the fall after it has had a whole summer to hunker itself down. A floating dock would be my preference in that situation.

Depth Range

The depth range for a fixed dock installed by a DIYer shouldn’t exceed much more than six feet or two meters. Installations kept within this range will be much easier for you to manage and will feel more stable than if you go deeper. If you must go deeper, then I would recommend the dock to be at least six feet or two meters wide. If permittable, an “L” or “T” shape dock providing a platform off to the side at the deep end will add stability. If you’re looking for enough depth at the end of a dock for swimmers to dive into, you’ll need no less than nine feet or three meters. I recommend discouraging any diving from the dock.

Your Assessment

If the fixed dock sounds like a good fit for you and your environment, step into the next chapter to learn how you can complete a thorough survey where you plan to put the dock. Now that you know the main criteria required, your site survey will verify specifics about the location that you’ll need to know before moving forward with a fixed dock.