Since 1998. we are engaged in cultural and natural heritage conservation and environmental preservation projects.

Our most important projects are:


The company Sub-merus started implementing the initiative “From river to the sea – let’s be plastic
free”. The organization benefits from support of Beyond Plastic Med. The initiative started on June
1st, 2023 and will be implemented till end of 2024.
The general goal of the initiative is to contribute to reducing the pollution of the Adriatic Sea with
plastic waste from the Cetina River.
The scope of this project is the area where the river meets the sea, namely the protected area of the
Cetina River Canyon and three areas of the Natura 2000 ecological network that spatially belong to
the city of Omiš. Despite the efforts to rehabilitate wild landfills, waste is still dumped in nature and
is very often blown by wind and rain over the vegetation of the Cetina River. These are various
categories of plastic that, due to their light weight, can be easily transported over long distances. All
this waste will ultimately end up in the Adriatic Sea from the river, and this is the reason why this
process should be stopped at the source in order to protect the increasingly endangered marine
environment. Sub-merus has been developing the activity of collecting waste from the Adriatic Sea
and the Cetina River for years. A Marine Conservation Volunteer Program was developed in
cooperation with ImpacTrip. In addition to diving education according to SSI standards, they
participate in all underwater cleaning activities. Through effective education, more than 350
volunteers from all over the world have been trained so far, and they have become our valuable tool
for spreading knowledge and experience on the topic of environmental and nature protection. In
order to increase interest in attending this program, with the help of the BeMed initiative, we will
expand our activities in such a way that volunteers perform ecological activities in addition to the
sea, also in the Cetina River canyon. Such a business strategy coincides with the provisions of the
Decision on limiting the use of plastic within the boundaries of the significant Cetina River Canyon
landscape adopted by the Public Institution Sea and Karst, which, according to the Nature Protection
Act, manages protected areas and areas of the Natura 2000 ecological network as part of this
project. Together with our project partners, the Association for Nature, Environment and Sustainable
Development Sunce and the Public Institution Sea and Karst, the following activities will be carried

  1. Establishment and implementation of protocols for collection, sorting, disposal of waste and
    plastic, and supervision
  2. Installation of containers for separate collection of waste and separation of waste at the point of
    origin and measurement
  3. Implementation of educational activities through workshops with the involvement of the local
  4. Education of all subjects about the harmfulness of plastic through social networks and through
  5. Raising public awareness by informing and organizing a media campaign against plastic pollution

Impactrip Marine Conservation Volunteer Program in Croatia

The Calypso Diving Center has been developing waste collection activities from the Adriatic Sea and the Cetina River for many years. Since 2018, the Center, in cooperation with the Impactrip company, has established a Marine Conservation Volunteer Program that brings together volunteers from all over the world. Our volunteers first learn how to SCUBA dive by SSI (Scuba Schools International) program, and then participate to cleaning of the seabed activities that are carried out each day throughout touristic season. We also provide specialized courses to volunteers eager to learn more about marine ecosystem such as SSI Marine Ecology or SSI Fish Identification courses. So far, more than 350 volunteers have been trained and several tons of marine litter have been collected and disposed of by the local municipal company. In 2021. we were the volunteer programme with most impact accounting for 7440 volunteering hours with 4T of trash collected from the sea bed. All volunteer efforts on the project work towards the vision of healthier oceans, thriving ecosystems and a clean coastline – all driven by an aware and inspired community.

EU project Wrecks for all

Wrecks4All project created an innovative tourism offer based on the underwater cultural heritage of the Eastern Adriatic region. Sub-merus ltd (Calypso DC) was engaged as service provider to the University of Split, Faculty of Maritime Studies (partner 4) to carry out many projects’ activities related to diving and underwater archeology. Stakeholders mapping and engagement was performed for the purpose of preparing an Action Plan for the management and touristic valorisation of underwater and cultural heritage. A curriculum on diving at cultural and historical heritage sites was prepared and 22 persons trained on underwater archeology, history of shipbuilding and photogrammetry. Training included in-class and underwater practical training. Sub-merus ltd. also conducted photogrammetric scanning of few shipwrecks in the Croatian part of the project for VR/AR tours and a virtual map of underwater heritage trails available to visitors in the Croatian Maritime Museum.

EU project Marine Natura 2000 sites of Split-Dalmatia County

During summer 2010, our Calypso diving center was engaged for mapping of the protected Natura 2000 site “Vrulja”. Divers, biologists – volunteers from the Association “Sunce” visited the site Vrulja (located at Dubci pass near Brela) for mapping of marine species and habitats. Vrulja owns its name from Croatian word “Vruljas” that means karst phenomenon of freshwater underwater wells that is precisely at this site one of the largest and most famous in the Adriatic. Species that live there are specific (i.e. Jewel Anemone – Corynactis viridis) for this site because of the constant upheaval of the sweet and cold water whose intensity varies with the rainy period. Water running out there is coming from a nearby mountain slope, and a large part of the border Biokovo Nature Park slope. Because of the small areas that occupy, “Vruljas” are endangered habitats, threatened by fresh water pollution, landfill, construction along the coast and dumping of trash in the karst. In the framework of the project an photo exhibition in collaboration with the Tourist Board of Omiš was organized on the 7th of October 2010.

Protection of the underwater archaeological site at the locality of Stanići – čelina

In the bay Mala Luka (Balića rt) at 25 meters depth, an archeological site of the ancient sunken ship that was carrying cargo of amphorae “Lamboglia” dating from the period of 100 years AC can be found. As during the past 40 years the locality was pretty devastated, we decided to initiate its protection. DC Calypso applied to Croatian Diving Association call for proposals with the project and succeeded to mobilize a certain amount of funds. Through the project we collected required documentation, permits and equipment and did the probe sounding and measurements. Excavations carried out in the period between January 15th, 2009 and February 15th, 2010 were monitored by the technical project manager archeologist and art historian Tea Katunarić from Academy of Arts – Split and the archeologist from the Ministry of Culture from Zagreb with the support of professional archeologists, volunteers, from the Netherlands Diving Foundation “Mergor in Mosam” chaired by Joost van den Besselaar.