22nd January, 2020

The Main Purpose of Dolphin Clusters

Not to be confused with the marine mammal of the same name, dolphin clusters are structures that stand near the shore and rise above the surface of the water. They’re not directly connected to the shore, docks, or bridges they’re built around. Usually, they consist of radial clusters of timbers or piles made of steel or plastic composite. You have probably passed them in coastal settings, but you may not have noticed them, as they’re generally unobtrusive. Despite this characteristic, they play a crucial role in any area in which they’re employed. Here are the main purposes of dolphin clusters.

Mooring and Berthing

Dolphins serve as structures that allow boats to moor, berth, or otherwise secure themselves near the shore. In mooring, the dolphin acts as a single fixed point to which a ship can attach with a line. In effect, it acts as a stationary anchor the boat can connect to rather than drop an anchor into the water. Dolphin clusters can also lengthen berths when there are more boats than the berth can accommodate. This is useful because the extra boats can still dock at the berth without the need to build the berth itself farther into the water. By forming lines with the dolphins, the boats can still dock firmly even though the structure isn’t necessarily continuous.


You can often find dolphins around marine structures such as bridges. Here, instead of acting as points at which ships can dock, they serve to form protective barriers that effectively deflect the force of passing vessels. The piers of a bridge, for example, can become unstable with the repeated battering of boats, making the whole structure less safe to cross. Dolphins alleviate this problem by absorbing the impact. Since they’re separate from the structure they surround, none of that force is transferred to the structure.

If you’re building a dolphin cluster for securing ships or protecting structures, consider using Tangent Materialsstructural composite lumber. Unlike most other materials, this plastic composite resists damage from marine organisms or ocean water.