The sides of the pier of Holwerd are covered with concrete blocks. Even though some vegetation is working its way through, the esthetics are mediocre. It would be much more beautiful to cover them with sand and vegetation!

Another reason to do this is that the environment of the Wadden Sea does not naturally have rocky shorelines. This can possibly lead to alien species living on the pier, which is harmful for the environment. For example, the pacific oyster (Crassostrea gigas) or the Northwest pacific crab (Hemigrapsus sanguineus).

To prevent the sea from taking away the sand, brushwood groynes can function as small dikes under the water untill the plant roots are able to hold the sand.

The pillars of the pier elongation do not provide much opportunities for nature. But attaching pole hulas around the pillars can be beneficial for nature. Pole hulas are hanging strings that are fixed around pillars. The strings are 6mm thick and 55cm long and they are attached just above and below the mean low water level. They are colonized by blue mussels and seaweeds, which both create habitat and food for other species, like amphipods and fish.