The project comprises the design of the following works:

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1 An integrated approach to the design of the port and marina infrastructure of the island of Mykonos D. Avgoustinos, N. Panagopoulos, I. Sioris TRITON Consulting Engineers Ltd, 10 Makedonon Str., Athens, Greece Abstract A new port and marina project has been designed for the island of Mykonos. The sensitive environment of the island and the impact of the works on the surrounding landscape have been taken into consideration both for the site selection and the operational needs of the project. Mykonos is unique among the islands of the Aegean Sea due to its picturesque landscape and traditional Cycladic architectural style. It is one of the most famous islands in Greece, visited by hundreds of thousands of tourists every year. The island is currently using the old and small traditional fishing port in the sea front of the city, whose congested basin serves ferry boats, day cruisers, yachts, fishing and sailing boats simultaneously. The numerous large cruisers arriving during the summer months remain anchored offshore using their launches to disembark tourists via the same port. The project comprises the design of the following works: A new harbour is designed 2 kilometres north of the city in relatively sheltered waters. An artificial island will be constructed close to the shore, but in sufficiently deep waters (10m average) to accommodate on its seaward side two berths for large cruisers (up to 200 metres long) and five ferry boat ramps. The artificial island will be connected to the nearby coast via a concrete bridge. In the water between the coast and the leeside of the island, a marina will be created offering shelter to 300 berths. Construction is to be tendered by the end of August, In addition to the above, a 240-boat marina just south of the existing harbour, and in close proximity to the town is envisaged. This facility will serve mostly international yachts of the highest class during the summer months. The

2 36 Marina location of this marina will provide easy access (walking distance) to the centre of the town and its facilities, will be of the highest standards, priced accordingly. A curved breakwater will create a sheltered basin, within which mooring jetties in the form of small islets will be provided. Landscape planning is to be provided so as to fully incorporate the new structure into the surrounding coastal environment. finally, a third generation residential marina is envisaged comprising 100 berths and respective apartments (to be constructed at a later stage). 1 Introduction Tourism is the principal and most important source of foreign capital into Greece. In 1995, tourist arrivals are expected to peak at a record of 11 million visitors. Tourism receipts should reach ECU 49 billion for the 1995 financial year, equal to the total of Greek export earnings in Mykonos and the nearby island of Delos together with the Athens Acropolis are considered throughout the world as the trademarks of Greek tourism. Mykonos is one of the central islands of the Cyclades group. Its geographical location at the centre of the Aegean Sea and the islands international airport makes it an ideal location to commence a cruise, not only to the Cyclades, but also to the Dodecanese Islands. A map of the area showing the location of Mykonos in the Aegean is included as Figure 1. Figure 1 The Location of Mykonos in the Aegean Sea Tourism in Mykonos has reached a point which is characterised during the peak season by a very high concentration of people, boats (ferry boats, cruisers and yachts) and cars. During the extended tourist season of the island the

3 Marina 37 simultaneous approach of 4 to 10 cruisers (each carrying between 200 and 600 passengers), 4 to 5 ferry boats (each carrying 120 vehicles and 650 passengers), catamarans, high speed passenger vessels and numerous large yachts is a common sight. This excessive growth in tourism has created many problems for the existing port. The traditional port reflected the rationale and needs of a past era and was structured to serve quite different functions. Unless a correct balance between the provision of new harbour works and the preservation of the island's unique character is not found, a decrease in the quality of the tourist environment and of the town itself, is the inevitable consequence. This is the rationale behind the design of the proposed new port works for Mykonos. The design was conceived as part of an integrated programme of infrastructure projects (ring road, out of city parking areas, etc.) that will allow the island to accommodate the continuously increasing tourism volumes without adversely affecting the environment. An integrated marina project must combine a large range of functions and consists of areas quantitatively and functionally quite different. These requirements are discussed further in the following sections prior to discussion of the final option. 2 Function Allocation The restricted size of the island's capital precludes any extension works at the existing old port. In addition, the allocation of all the required functions in the same area would create an installation of disproportionate size in comparison to the island's small scale structure. The new port and marina complex will therefore comprise a number of operational parts allocated in specific areas according to the functional requirements, and the quality of the existing environment (see Figure 2). The new port and marina infrastructure of Mykonos will service three main types of tourist traffic: i II Hi Ferry boats Permanent yachts Transient yachts A luxury marina will be located at Agios Haralambos. The marinas proximity to the town ensures that the facility will be fully integrated with the town and its resources. However, the proximity of the site to the town also requires attention to design detail to ensure that the final facility can be easily incorporated into its traditional surroundings. This high standard facility will also help to upgrade the natural environment, creating a new entrance to the town from the sea. The new passenger and tourist port is proposed for Tourlos, a site located approximately two kilometres north of the main town. This facility will include user-specific areas for ferry boats, cruisers and yachts. Throughout the design, and further to the primary goal of satisfying functional requirements, emphasis has been given to the harmonious integration of the facility with the island's unique environment.

4 Proposed Tourlos Marina-Port Integrated Installation Existing Traditional Harbour of Mykonos Proposed Marina at Agios Haralambos Proposed Future Residential Marina CO ; M Figure 2 Master Plan of Proposed Port Works for Mykonos

5 Marina 39 A garage marina servicing the requirements for long term storage of yachting vessels will also be located at Tourlos. This facility has been designed as an offshore island, and will provide the only safe shelter for yachts in the Cycladic region. This construction is unique as it combines the function of the marina on the lee side of the offshore island with ferry boat stern berthing on the exposed side. It is anticipated that there will also be an exceptionally high demand for dryberthing facilities. The land components of the Tourlos installation are provided to service these requirements. The dry-berth will provide facilities for cruisers from all over the Aegean and even the Eastern Mediterranean Sea. Due to the nature of such facilities, they have been located at Tourlos, away from the town and the proposed high standard luxury marina. A future residential marina is also proposed for Tourlos. This facility will further enhance the quality of offered services, and will specifically be aimed at the higher income tourist. By allocating all the above services away from the existing harbour we ensure that the traditional character of the harbour will be preserved, if not also improved in comparison to its present condition. 3 The Agios Haralambos Marina The functional requirements for the new marina are clearly defined. In addition to these requirements, the main criterion in the design of the new marina for Agios Haralambos is to preserve the existing appearance of the town. Agios Haralambos is in the direct line of sight from one of the main vistas from the town across the windmills to the sea. The proximity of the proposed marina and its location relative to the town therefore required special consideration during the design phase. In place of a conventional harbour, a unique curved-plan breakwater is provided, with a specific longitudinal section. The proposed design is intended to blend harmoniously with the surrounding landscape. The proposed design is included as Figure 3. The marina consists of two artificial islands with curved perigrams (see Figure 3). The islands are connected to the coastal quays via bridged light constructions which allow water to circulate freely thereby hindering formation of standing water. The entrance to the marina will be marked by two stone columns suitably founded on the breakwaters' heads. A detail of this entrance feature is shown in Figure 4.

6 40 Marina Figure 3 Proposed Marina at Agios Haralambos (Model) Figure 4 Marina Entrance at Agios Haralambos (Model) To minimise the impact of the breakwater when viewed from the coast it has no longitudinal piers or quays on its lee side, and its crest has been kept as low as possible (a maximum of +2.00m above mean sea water level) Berms are provided along the structure's toe which force waves to break before they reach the slope. This form of construction reduces the energy impact of breaking waves on the structure and allows the crest to be lower. The breakwater will be constructed with quarry stones.. The superstructure of the berths has specifically been designed using the local natural stone, granite, and prefabricated beams of white concrete with pebble surfaces. These materials were chosen to ensure that the aspect of the final facility will be appropriate to the surrounding environment.

7 Marina 41 Every effort has been made to facilitate the construction by employing pref abrication wherever possible. The interiors of the artificial islands will be formed by graduated layers of material which will be landscaped with native trees, thereby re-creating the landscape so characteristic to Mykonos. The marina will accommodate 240 boats with emphasis on the middle and high classes (III and above according to the PIANC classification), as shown in Table 1 below. Table 1 Breakdown of Berth Numbers and Yacht Classification PIANC Yacht Classification I II III IV V VI VII VIII Totals Length, (m) <8m 8-10 m m m m m m m No of Berths Provided Percentage of Total Berths The Tourlos Marina-Port Integrated Installation Tourlos is relatively sheltered from the predominant winds and waves of the North Sector Gulf and is the site chosen for the construction of the new passenger and tourist port. The new port has the facilities required to cope with the ferry boat and cruiser traffic even during the summer peak. The site is ideal as it is located within two kilometres of the town, combines favourable sea bottom contours, a wide sheltered gulf, and is an unsuitable location for swimming. The berths will be constructed as an offshore rectangularly shaped island approximately 600m long (see Figure 5). This solution avoids the need for the conventional heavy and expensive protective works and breakwaters. The artificial island will blend into the surrounding coast and hills and will create a completely sheltered water basin on its lee side. The facility incorporates areas for a marina (with berths for 320 boats) and land areas for dry berthing and boat repair works combined with a ramp and travel-lift.. A wave absorbing structure has been incorporated into the face of the vertical quay wall where ferry boats and cruisers berth. The structure was designed to ensure that there will be no more than three days during the summer months when the predicted wave conditions will exceed those specified for the smooth operation of ferry boat terminals. The installation can simultaneously accommodate two cruisers (side berthing) and five ferry boats (stern berthing),

8 bo Dry Berthing Travel-lift ~ and Ramp Car Parking and Waiting Areas F/B Passenger Terminal Marina Administration 3' Figure 5 Proposed Marina-Port Integrated Installation at Tourlos

9 Marina 43 The only difficulty anticipated for construction at the site is the presence of a loose sand surface layer on the sea bottom. This layer will be improved by the method of vibro-compaction (compaction by means of vibro-float). Berths were designed using prefabricated reinforced concrete caissons. Each caisson measures 18.30m (length) by m (width) by 12.30m (height) and is divided into eight cells each measuring 3.90m by 3.90m. Only the back cells are fully stone filled while the front cells are partially filled to keep the toe pressures as low as possible. Closer to the coast, shallow water and more favourable sea bottom geotechnical conditions render the use of caissons unnecessary. In these areas, the leeside of the island as well as the quay walls along the coast will be constructed with concrete blocks. The mainland and coastal works are connected by use of a partially prefabricated reinforced concrete bridge. The bridge was designed to achieve the minimum possible thickness of the slabs both for aesthetic reasons and in order to allow passage of smaller boats underneath it. The Tourlos marina will comprise three distinct areas for ferryboat, cruiser and yachting (marina) traffic. The Ferry Boat (Passenger) Zone comprises a total area of 25,500 square metres. It includes the main passenger arrival terminal and designated parking areas for hotel minibuses, taxis and buses. The departure area for ferry boat passengers,, including waiting areas for cars is located west of the passenger arrival terminal. The Cruiser Zone includes a central tourist information and service area, duty free shops, banks and other amenities. Due to the extensive size of the cruiser zone, three longitudinally placed and covered areas have been provided as waiting areas for cruiser passengers in order to provide ease of access for all cruiser passengers. In the architectural planning of the proposed land areas, special consideration was given to each element comprising the Marina Buildings were kept below a maximum designated height to ensure that the construction would not be conspicuous when viewed from the town. All materials used for both construction and facades were sourced locally as far as possible. Special care has been taken in the design of the superstructures of the harbour works, the bridges, the beacons, and the heads. Roads are asphalt paved and where necessary, coloured block pavers delineate the various road uses. Pedestrian areas such as roads, walkways and malls will be paved with pebble-surfaced mosaic tiles or granite tiles. Secondary pedestrian areas will be paved with crushed rock. Other landscape components such as the low level lighting, benches, lighting towers and even the litter bins were also specifically designed for the complex. Attention to such details ensure that the final facility will meet the high demands imposed both functionally and in relation to the natural and traditional environment of Mykonos. The cost for the construction of the offshore island amounts to 6 billion drachmas and it will be financed mainly by the Cohesion Fund. The harbour and infrastructure works have already been tendered and construction is expected to commence early in 1995.