It is inevitable that every big destination city has problems managing tourists and traffic, which can have many negative effects. One such example is Venice, Italy, which experiences millions of tourists annually and has a heavily used transportation system. This transportation system is based mainly on boats due to the fact that Venice is a series of islands with a canal system. These boats produce wakes or moto ondoso, which destroy the canal walls over time, causing structural issues. The moto ondoso also presents a safety issue, as small gondolas or sail boats are prone to being capsized by the high-amplitude waves. This project addressed the various transportation systems present in Venice in order to try and reduce moto ondoso, saving the structural integrity of the city’s canal walls and maintaining safe water travel.
The transportation system of Venice is based into four main categories, of which this project will be evaluating public, cargo, and taxi transportation. The public transportation system accounts for about 21% of the overall transportation system, and consists of ACTV vaporetto boats and Alilaguna boats. The cargo boats account for about 36% of the overall system and are essential to delivering packages throughout the city. Taxi boats account for about 25% of the system and are used heavily by tourists, often going to and from the Marco Polo airport. All of these boats use a variety of hulls, many of which are not suited to the low-speed water travel present in the Venetian canals. This study first determined potential improvements to cargo transportation, then public transportation and taxi transportation. It then looked at how the hulls used by these three transportation systems can be improved to produce less wake at low speeds.
Our suggested improvements to the cargo transportation system centered around reducing the number of stops a cargo boat makes to deliver its goods throughout the city. According to a 2013 study, the boats in the cargo delivery system travel about 3,000km, or the distance from Venice to Iceland, to deliver about 32,000 packages throughout the city every day. The delivery routes are highly inefficient due to the way the delivery system is organized. Cargo is transported through the system by product, meaning that boats will pick up a particular type of product and will then go from stop to stop across a number of the Venetian islands to deliver a small number of packages to each. A study in 2001 analyzed the transport system and suggested a switch to by location delivery, where boats would be filled with the different types of packages going to one location and would go to just that single location. They split Venice up into 16 delivery zones, each of which would receive roughly even amounts of cargo. The 2013 study estimated this would reduce the distance travelled to 400km, or an 86% reduction in travel. This study also renewed the zone system, updating the 16 previous zones to be composed of 42 different zones using updated store and package delivery data. The City of Venice has built a warehouse, the Interscambio Merci, that was to be used to receive and organize the cargo coming into Venice for switching to delivery by-location. It was built over a decade ago but continues to sit unused. The city recently put the warehouse up for bid to cargo consortiums with a €500.00 per year rent, but as of the end of December 2015, none had been accepted.
We sought to incentivize the switch to by-location delivery in the form of a rent reduction on the warehouse. Whichever cargo consortium wins the bid would have to organize their cargo transporters to act as efficiently as possible. Efficiency of their delivery routes would be evaluated and their rent would be reduced by a certain amount proportional to the increase in efficiency. To achieve this, a set of efficiency rules were developed based on by-location strategies, making them unachievable if cargo transporters were to continue using a by-product delivery system. The rules centered around minimizing the number of zones any one boat could go to each day, and making sure the boats followed the speed limit, as travel distance and speed are the primary components of moto ondoso. An example of such a regulation and the associated rent reduction is provided below.
Additionally, the number of boats required for each zone was estimated using package volume and cargo boat capacity data from previous studies. By estimating how many standard and refrigerated cargo boats are required for each zone, further regulations were developed which would dictate how many boats the consortium would be allowed to send to each zone, contributing to the rent reduction. The number of boats per zone is provided in the figure below.
A GPS modules was used to test the feasibility of using such a system to track boats and their efficiency. Although we encountered issues using it on a cargo boat due to short battery life, travel was estimated by walking around Venice with the tracker. It was found that speed, stop, and zone information could be determined from GPS data and as such it is a viable system for tracking. Overall, the study concluded that an efficiency incentive system could be used to switch to a by-location delivery system, that the incentive would come in the form of a reduction in rent on the Interscambio Merci, and that a GPS tracker could be used to put this system in place.
Increasing the efficiency of the public transportation system in terms of passenger transportation from cruise ships was the second objective of this project. One past project determined that 25% of over 3,000 passengers per ship choose boat transportation, but increasing the efficiency of the boat transportation from cruise ships has not been addressed before. We found that this system is immensely inefficient, as nineteen of twenty-four total boats coming from two cruise ships were determined to be empty, while the remaining five boats were not filled either. Two of these five boats were double decker boats, one of which was 71% empty and the other 65% empty, and the remaining three of the five boats were Alilaguna boats about 90% empty. These inefficient boat counts can be seen in the figure below. This is extremely inefficient because these boats are not transporting any passengers, and are therefore creating unnecessary moto ondoso.
We addressed this problem by improving the Alilaguna Linea Blu schedule and synchronizing it with the cruise ship arrivals, since Alilaguna boats are lighter and produce less moto ondoso than double decker boats. In order to increase the efficiency of the system, “bursts” of Alilaguna boats will be sent to the cruise ship terminal when a ship arrives. Each of these bursts will include an additional boat every half an hour for the three hours that it takes one cruise ship to unload. During each of these unloading periods, this would mean three additional boats per burst on top of the three existing hourly scheduled boats, totaling six boats per ship unloading. Furthermore, the bursts were synchronized with each cruise ship arrival so there was one burst per ship arrival. If 25% of the 3,553 average passengers per ship (889) choose boat transportation when unloading, then these six Alilaguna boats with a capacity of 160 each will take care of all applicable passengers. This system will be further synchronized by accounting for multiple ships per day, different passenger count numbers for different seasons, and by adjusting in advance based on updates about cruise ship cancellations or delays.
This system will eliminate unnecessary, empty boat trips by discouraging other boats from going to the terminal, and will ensure that boats are filled with passengers. The boats will be filled due to the increased incentive of the Alilaguna boats coming every half an hour during unloading times as opposed to the previous hourly basis. This solution will therefore make the overall boat transportation system for unloading cruise ship passengers more efficient and decrease moto ondoso production.
Currently, the taxi system contains several inefficiencies that increase the amount of moto ondoso in the city of Venice. Taxis are responsible for approximately 25% of moto ondoso within the city. Excessive amounts of wake are created due to inefficiencies within the system and certain regulations from the city. When on call, taxis must return to their stands empty after delivering customers to their destination rather than immediately picking up a new party. Some canals are also restricted from travel, making taxis have to travel a longer route to reach their destination. Taxis also cost 70-100 euro, making it one of the least used forms of transportation in Venice.
In order to increase the efficiency of the taxi transportation system, the total amount of miles travelled with passengers should be increased while the total distance travelled should be reduced. It was determined that ride sharing would address both issues. The process would involve separate parties riding in one taxi, getting delivered to their destinations, and paying a split rate. To establish the feasibility of ride-sharing, several rounds of interviews were conducted with tourists. Two interviews took place at the Marco Polo airport and Piazza San Marco with questions concerning tourists’ trip length, transportation use, and ride-sharing preferences.
Of the 58 people surveyed, only 14 had used taxis while the rest used the ACTV and Alilaguna boats. When those who did not use the taxis were asked if they would consider using a taxi, 32 said they would not while 12 said they would. When asking all those who did not take taxis as to why, 38 said that they were too expensive while the other 6 had some lack of knowledge about the system; those lacking knowledge either did not know how to use a taxi or did not know that it existed. When all were asked what the minimum discount they desired to share a taxi, the majority wanted a 30% discount. The maximum time the majority of people were willing to wait for another party to join them and reach their destination was 20 minutes.
The results of the surveys indicate that taxi sharing has potential in Venice. We recommend that the rule preventing taxis from immediately picking up new customers after delivering their prior ones should be eliminated; this shall reduce the number of unproductive trips taxis make and thus reduce any unnecessary moto ondoso created. We also recommend opening up the Arsenale canal as well as create shortcuts to the airport and the cemetery the drivers will travel a smaller distance and create less moto ondoso.
Our last method of reducing moto ondoso was to change the boat hulls that are currently present in the city, so that they create less wake at lower speeds. Anything that floats creates waves, and the two factors that affect wave formation are hull shape and hull weight. Some of the boats that are currently in the lagoon are not necessarily ideal for the layout of the city. The maximum speed limit in the lagoon is 20 km/hr, and some of the planing hulls are only efficient past those speeds. There have been several previous efforts to create hulls that create less moto ondoso; however most of them have failed to do factors such as cost and political acceptance. Because of this, we had to consider several things before creating our new hulls. We wanted to make sure they created less wake, weighed less, cost around the same and looked the same. In order to create new and efficient boat hulls, we first had to measure and model the current boat hulls in the city. We did this by visiting several boat manufacturing companies and taking measurements and pictures of taxis and an Alilaguna. We then took these measurements and met with a local Venetian naval architect who taught us how to use Rhino, which is a 3D modeling software. We modeled the three boats in this program, and then changed the hulls to be more efficient. These changes included editing the bow, chine and keel as well as the overall structure of the boat. We then took the current and new hulls and ran them through a hydrodynamic analysis program called Maxsurf in order to get the hydrostatic parameters of the boats. The highest speed allowed in the lagoon is 20 km/hr therefore we took the resistance values for all the boats at this speed.
We were only able to run the taxi hulls through this program because we did not have enough time to run analyses on all of our models. Solely from changing the boat hull, we calculated that were would be a total increase in efficiency by about 19%. When we kept the boat hulls the same, but decreased the weight from our structure change, we calculated an efficiency increase of 10%. This would be a total increase in efficiency of approximately 29%. Due to the fact that we changed the exact same parameters across all of our boat designs, we can confidently say that the Alilaguna and cargo boats will also have about a 29% increase in efficiency. The two components of total resistance are skin friction and wave formation. Since we know the overall resistance decreased, we know the wave formation also decreased. In order to actually calculate the decrease in moto ondoso, a future study should be done to tweak our design and rerun them through Maxsurf. Then, scaled models should be built and tested in a towing tank to calculate the actual wave formation. If all goes well, our new hulls would be able to be sold to boat drivers within 5 years. Ideally, if our new hulls are bought, then the buyers would receive a discount from the city for being eco-friendly. In the future, all taxi, Alilaguna and cargo boats should be switched over to our new hulls in order to drastically reduce the damaging effects of moto ondoso.