15th October, 2020

Design Criteria for Boat Ramps

Since people move their boats to and from their homes on trailers that they pull with land-based vehicles, they need a way to lower their boats into the water and lift them back up. It would be impractical to expect people to simply carry their boats from the trailers to the water themselves. This is why boat ramps exist in certain areas. They are structures that allow boat owners to easily get their personal vessels into bodies of water and to pull them back out. Like any sizable structure, there is a great deal of planning that must go into their construction, though. Inform yourself on these common design criteria for boat ramps so you may create a ramp site that is practical.

Consider the Ramp Site Details

The location of your ramp or ramps determines how you approach their assembly at just about every subsequent step. Therefore, you must pick it wisely, making sure to consider its features and how they will affect you later on. A detail you may look at initially with regard to the site is how accessible it is. You should preferably aim to have the ramp area near existing roads to decrease the extent of construction and maintenance it needs, while also making it convenient for people to arrive there once it is completed.

Another factor to consider is the landscape of the location. If you foresee that you will need to perform a large amount of digging and filling to level the ground, it may not be worth the expense to start making a ramp there. Furthermore, the water conditions at that site should be ideal for people. A strong current, winds, and a close proximity to other ramp sites can make using the ramp more difficult. You should find a location that is free of these issues where the water is calm and conducive to the act of moving vessels in and out of it. This will reduce the likelihood that people will get injured while there.

Settle on the Ramp Area Size

You must also settle on how much space you want for the parking lot that will sit adjacent to the ramp or ramps. More than the quantity of ramps themselves, the size of the parking lot will determine how many people will use the area. The number of ramps you include is actually dependent on how many parking spaces you set out. Settling on the right ramp area size is crucial because it is the means by which you control the number of vessels that are out on the water. You must think about what is safest for boat owners and how much noise/water and disruption those who own properties around the ramp area are willing to tolerate.

An additional limiter on the parking size is the time it takes people to launch and retrieve their boats and park or unpark their corresponding trailer-towing vehicles. There will no doubt be peak hours when boat owners are waiting to use the ramps. You should not make the parking lot so big that it takes more than about five minutes for an individual party to complete a launch or retrieval in its entirety. If they must drive a greater distance to park or must walk far to bring their vehicle to the ramp, this will slow the process down considerably and hinder those that are waiting their turn.

Select the Boat Ramp’s Slope and Depth

There are four major components to a boat ramp’s dimensions that you must carefully adjust so that it functions excellently. The first two are the ramp’s slope and depth. With the slope, you want to achieve an angle that is ideal for lowering a boat-holding trailer into the water without having the towing vehicle touching the water. If the ramp is too level, the vehicle will need to partially submerge itself to get the boat deep enough to start moving on its own. On the other end of the spectrum, a ramp that is too steep can cause the vehicle to slip down into the water. The working standard for ramps to achieve a nice medium is seven to eight and a half degrees, or twelve to fifteen percent.

When it comes to depth, the top of the ramp should sit above the water level at all times. You must take into account the fluctuations in the tide as a result. The bottom of the ramp, or toe, should be deep enough that its surroundings don’t shift quickly due to erosion. Know that your ramp may not remain useable through all seasons, so you should ensure that its top and bottom heights are accessible during those times of the year when people want to bring their boats to the water.

Design the Boat Ramp’s Width and Alignment

The other two-dimensional factors besides slope and depth are width and alignment. You must provide ample width on the ramp so that people can comfortably maneuver their vessels and vehicles while on it. This means that the ramp should be wide enough for trailers and vehicles to fit, with several extra feet on either side. They can then move straight down or up its length and will have space for making turns. The standard width for a single lane on a boat ramp is about twenty feet, where ten feet make up the primary width and there are five feet on each side that act as buffer zones.

Alignment refers to the orientation of the ramp relative to the body of water. It is most applicable to rivers because their waters flow in a set direction, and the positioning of the ramp can thus change how easy it is to launch and retrieve boats. The most common alignment is one where the ramp sticks out at ninety to forty-five degrees in the direction of the water’s flow. The closer the angle is to that direction, the easier it is for boat owners to use the ramp. Some ramps are even nearly parallel to the water’s course, though this does require more upkeep due to sediment movement. You want to avoid having a ramp pointing against the current, as this will make it much harder for boats to maneuver in and out of the water.

As you follow these design criteria for boat ramps, you may also want to establish side docks to guide boats and allow them to come to secure stops there. To build them, you should use a material that is both stout and does not degrade in water. The structural composite lumber that Tangent supplies checks these boxes and is great for aqueous environments. If you’re interested, give us a call today.