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.
CHAPTER 5:
COMPLETING THE SITE SURVEY FOR A FIXED DOCK
Now that we’ve considered the best conditions for a fixed dock, let’s see if one will be a good fit for your waterfront. When I visit a shorefront to measure for a fixed dock, I am sometimes unfamiliar with the body of water, so I will start with these questions.
• Where should the dock begin at the shore?
• Where will I set the first set of dock legs?
• Is the water level somewhat stable here?
• What is the exposure here to waves and current?
• What direction does the predominant wind come from and is it formidable?
• Is the ground firm and stable?
• Will it be in an acceptable depth range?
Perhaps you’ve had plenty of time to become familiar with the waterfront where you’ll be installing a dock; in that case, you’re ahead of the game. Almost half the time, when I meet with people about building a dock, they are unfamiliar with the nature of their shoreline, perhaps they just bought the property, so a little detective work is in order.
Choosing a suitable location: Quite often there is clearly one place the dock can go off a property, be it a narrow lot, code-restricted area, or proximity to adequate depths. Otherwise, if your waterfront gives you options, here are some things I would consider. Begin with a comfortable elevation off the water. If possible, avoid having to build stairs or an extra-long ramp that will require needless climbing when there is a lower approach nearby that could be used instead. See that the location provides the right depth for your boat and activities while being free of obstacles. If there is a barrier with a leeward side from wind and storms, take full advantage of it. For privacy’s sake, keep a comfortable distance from the neighbor’s dock. The huge pine tree at the water’s edge could offer shade for the dock if that’s your thing, but keep in mind that it could also rain sap and soot. A dock at the side of a swimming hole is preferred over a dock that is in the swimming hole. The same can be said for the scenic view; it is better to keep the dock on the side rather in it. I guess that depends on what you’d rather look at, the dock and boat or the water and mountains behind them. Having it where you can see it without spoiling the vista would be ideal. Finally, make sure you include your significant other on this one. It’s much easier to move an idea than the real thing.
Establish the location of dock legs nearest to the shore: Their location will set the course for placement of all the other dock legs. Most of the DIY docks in this book are comprised of standard- size sections that become building blocks adjoining to one another. Each section typically gets two legs at its farthest end. It may be your preference to place the first set of legs above the shoreline to support the shore end of the dock section or place them out into the water at a distance so that the shore end of the first section rests on dry land.