An Integrative and Sustainable Workplace Mobility Plan: The Case Study of Navantia-Cartagena (Spain)

: The United Nations Sustainable Development Goals have been the strategic aims of many interventions in society recently. Navantia has developed a Sustainable Workplace Mobility Plan motivated by Sustainable Development Goal 11, Sustainable cities. Navantia is a leading Spanish company in the design and construction of high technology military and civilian vessels. This project is focused on the Navantia facilities in Cartagena. A workplace mobility plan has been developed to encourage sustainable mobility, promoting access on foot, by bike, by scooter, and using public transport to travel to and from the company’s facilities. The methodology used is based on the European Guidelines for developing and implementing a sustainable urban mobility plan. Thus, the current accesses and their mobility characteristics have been studied in detail, and surveys have been conducted among the company’s employees. A diagnosis of the situation has been elaborated. To solve the identiﬁed problems, three sets of measures have been developed: (i) improved access measures; (ii) management of car park areas; and (iii) soft measures. The economic cost of all these measures has been estimated, as well as the related carbon savings. As a result, a complete sustainable workplace mobility plan has been designed from an integrated point of view to encourage sustainable mobility, not only for the company’s employees but also for all the inhabitants of Cartagena, to transform the city into a place with good quality of life now and in the future. This practical case can serve as a reference for other companies that want to foster sustainable mobility among their employees, even when they are subject to urban constraints.


Introduction
Work mobility is the main reason for daily commuter trips in urban and metropolitan areas [1,2]. Work mobility is defined as the set of movements, of people and goods, that occurs in a company and its surroundings. Cars are the mode of transport that is used in the greatest proportion, despite being an inefficient alternative due to energy and space consumption. Some of the well-known negative impacts of cars are an increased number of accidents, emissions, and expenses, and loss of time. Thus, it is necessary to consider other forms of transport, such as walking or using bicycles, scooters and public transport [1][2][3].
In recent years, the European Union has increasingly focused on the development of sustainable urban transport and has introduced directives, guidelines and numerous projects and initiatives [4][5][6]; for example, the Urban Mobility Observatory ELTIS website [7], where the essence of a Sustainable Urban Mobility Plan (SUMP) is explained in detail; or the CIVITAS SUMP project [8], which evaluates the implementation of measures in the economic, energy, environmental, social, and transport areas in space available to build new infrastructures. The objective of the plan is to reduce the use of cars to improve the quality of life, not only in the company environment but also in the city of Cartagena.
This study, and its future implementation, is aligned with the Sustainable Development Goals (SDG) that guide current interventions in countries. Specifically, it is motivated by SDG 11-Sustainable Cities and Communities, as it seeks to provide access to safe, affordable, accessible, and sustainable transport systems for all and to improve road safety. In addition, strengthening positive economic, social and environmental links between the different areas of the city of Cartagena and Navantia are among the expected results, thereby fostering local and regional development planning.
This SWMP is explained in the paper. In Section 2, the methodology used is briefly described. In Section 3, the current situation from a mobility point of view is characterized. Section 4 explains the main results of surveys given to the company's employees. In Section 5, the proposals for improved mobility are described, and conclusions are drawn in Section 6.

Methodology
A sustainability planning process must be comprehensive and integrated. It should consider all the significant objectives, impacts and options. Hence, this SWMP has followed the European Guidelines for SUMPs [9] (Figure 1). The SUMP cycle consists of four phases, each of which is subdivided into three steps (for a total of twelve steps in the planning cycle). All four phases of the cycle start and end with a milestone. The milestones are linked to a decision or an outcome necessary for the next phase and which mark the completion of the previous phase. Steps of Sustainable Urban Mobility Planning. Source: Guidelines for developing and implementing a sustainable urban mobility plan (2nd Edition). Rupprecht Consult (editor). 2019. [9].
In this paper, only the results of activities 3 and 7 are explained for brevity. Activity 3 (analyze mobility situation) is the final task of the first phase where the planning context is defined. Existing plans or legal requirements are identified; the mobility situation from the perspective of all transport modes are analyzed; and the participation of employees is considered to learn their opinions about the existing access and their views about the travel plan. Numerous meetings have been held among the managers of Navantia and the planning team to define the strategic direction of the SWMP. This fluid communication has allowed us to develop parts of phase three, specifically, activity 7 (select sets of measures), where sets of measures are chosen to achieve the agreed-on objectives and targets. At the time of writing this document, the measures were being presented to political stakeholders and the public.
Specifically, the methodology used consists of the following steps: In this paper, only the results of activities 3 and 7 are explained for brevity. Activity 3 (analyze mobility situation) is the final task of the first phase where the planning context is defined. Existing plans or legal requirements are identified; the mobility situation from the perspective of all transport modes are analyzed; and the participation of employees is considered to learn their opinions about the existing access and their views about the travel plan. Numerous meetings have been held among the managers of Navantia and the planning team to define the strategic direction of the SWMP. This fluid communication has allowed us to develop parts of phase three, specifically, activity 7 (select sets of measures), where sets of measures are chosen to achieve the agreed-on objectives and targets. At the time of writing this document, the measures were being presented to political stakeholders and the public.
Specifically, the methodology used consists of the following steps: 1.
Creation of an inter-departmental core team and definition of the research goals. The workgroup is created with Navantia representatives and transport engineers. This group allows orienting and limiting the scope of the plan to be developed, since the general objectives to be pursued are defined. 2.
Literature review. Documents on sustainable workplace mobility plans such as policy documents, academic papers, technical reports, and case studies are reviewed.

3.
Definition of planning context and data collection. Factors that will have an impact on the planning process, such as existing plans or legal requirements, are identified. A detailed study of the company's accesses and their mobility characteristics has been carried out to determine the transport infrastructure. In addition, surveys to all the employees were conducted to find out the schedules and transport modes used to access the factory. 4.
Diagnostic assessment. Data from the previous step has been analyzed to elaborate a diagnosis of the situation. Problems to solve and opportunities to take advantages related to mobility are identified. This stage is the starting point of the proposals described in the next step. 5.
Measures planning. Strategies to achieve a sustainable workplace mobility plan are proposed. Different solutions to solve the identified problems are described with an approximate budget of their execution cost.
The objective of these proposals is to encourage sustainable urban mobility, promoting access on foot, by bike, by scooter, and using public transport to travel to and from the company's facilities. Intermodality and synergies among the different modes of transport, together with the management and regulation of parking lots to minimize conflicts among the different modes of transport, are the ultimate goals.

Characteristics of Study Area
Navantia is a leading Spanish, state-owned company in the design and construction of high technology military and civilian vessels with strategic facilities in the Spanish cities of Ferrol, Cádiz, Madrid and Cartagena. Navantia also maintains subsidiaries, offices and delegations abroad, which allows the company to work closely with clients and partners in strategic markets, such as the USA, Brazil, Norway, India, and Australia, among others.
This SWMP is focused on the facilities in Cartagena, which have a total of 2500 employees (including auxiliary industries). The main characteristic of this company is its location. Unlike other companies or industrial areas located outside of cities, an important conditioning aspect of this company is its physical limitations inside the city. Navantia-Cartagena's boundaries are established by the Cartagena Military Arsenal to the North, the Rambla of Benipila to the West (an intermittent river) and the Castle of Galeras to the South (Figure 2). Several items have been studied in detail to characterize this area, in particular: an inventory of streets, accessibility, car parks, cycle-lanes, public transport, and urban planning conditions. Only the main conclusions of each issue are shown.

Access Routes
Navantia-Cartagena has two access routes, the Algameca road, for all types of vehicles and pedestrians, and the Elephant walkway, for pedestrians and non-motorized vehicles; that is, personal mobility vehicles like bicycles and scooters ( Figure 3). From the pedestrian point of view, the Algameca road is the only one with pavements, an acceptable road surface and enough lighting and signaling, although this infrastructure could be improved for intermodal mobility. In contrast, the Elephant walkway has a deteriorated surface, insufficient lighting and signage and poor maintenance ( Figure 4). Although there are nearby bike lanes, none of the access roads to the company have bike lanes. Thus, it is difficult to access the factory using this mode of transport due to the lack of infrastructure facilitating direct connections ( Figure 5).

Public Transport Stops
Regarding public transport, there are 10 bus lines stopping at an acceptable distance from the company (1500 m in the case of the farthest) ( Figure 6). However, the schedules and frequencies make it difficult for employees to use. It is necessary to improve the operation of these lines. From the point of view of intermodality, Cartagena has three stations (FEVE, RENFE and bus station) located approximately 2 km away from the closest access to Navantia. This distance is too far for pedestrians, considering that it takes between 25-30 min. to walk. However, it could be possible to travel by bicycle (6-8 min) or with a shuttle bus service.

Modal Split to Navantia Access
Navantia has six access points: Cortadura, Santa Rosalía, Carenas, Carenero, one reserved for heavy vehicles, and one from the Arsenal military facilities (limited to authorized personnel only). In relation to the Cortadura entrance, Figure 7 shows that 84% of the entries are produced on foot because of its proximity to the city center; 10% correspond to employees who use bicycles as their means of transport and the remaining 6% access using personal mobility vehicles like scooters. Santa Rosalía is the main entrance to the factory for employees and visitors, and it allows entrance to all modes of transport; that is, motor vehicles, pedestrians, cyclists, and scooter users. Considering that there are two large car parks nearby, 76.6% of the entries are on foot, while 19.6% correspond to workers who enter the factory in their own vehicles; 3.3% of employees choose to use bicycles to go to their jobs and only 0.5% use a personal mobility vehicle at this access ( Figure 7). The Carenas and Carenero entrances are only for pedestrians and authorized employees. In general, 78.1% of employees gain access on foot, 17.8% enter by car (only those who enter inside the factory by car are considered), 3.7% of employees use bicycles, and 0.4% of the staff members use a scooter or similar personal mobility device ( Figure 8a). Moreover, Figure 8b shows that Santa Rosalía is the main entrance to the factory because 90.7% of workers use this access on an average day. The Cortadura access is used by 5.9% of employees, whereas the Carenas and Carenero entrances, both only for pedestrians and authorized employees, are used by 3.4% of workers.

Car Parks
Navantia-Cartagena has a total of three conditioned car parks with 1002 parking spaces overall, of which 857 correspond to four-wheeled vehicles, 143 are for motorcycles, and 2 are exclusively for people with reduced mobility (Figure 9a). On the other hand, there are three other unconditioned parking areas with approximately 183 parking spaces (Figure 9b).

Urban Planning Conditions
Because of the geographic location of the factory, there are several limitations due to the different conditions arising from protection to forest, hydraulic, maritime, and defense areas. This set of conditions is an obstacle to overcome in order to carry out the proposals described in the following sections. The most relevant one is that related to the Public Hydraulic Domain because all the roads are affected by rain with a return period (T) of 50 years ( Figure 10), extreme events which are increasing due to climate change. In short, Navantia has two access roads, the Algameca road and the Elephant walkway. The Algameca road does not have bike lanes and the width of its two pavements is insufficient for use by pedestrians with a minimum degree of safety; while the pedestrian path is in poor condition with faulty paved surfaces and insufficient signage and lighting.
Navantia has six access points. However, the fact that 90.7% of employees access the factory through the Santa Rosalía entrance causes traffic jams during peak hours (6.00-7.00 and 14.00-15.00). The rest of the accesses, Cortadura, Carenas and Carenero, are used by the remaining 8.3% of workers.
There are car parks outside the facilities, however, there are no bike lanes, and it is necessary to improve the characteristics of the public transport lines to provide a good enough service to make the use of buses a viable option.

Analysis of Mobility Survey Results
A survey was conducted to learn about employees' mobility patterns during the first 2 weeks of March 2020. That date has been decided for considering normal weeks, without holidays or extraordinary activities of the company. A total of 496 anonymous surveys were received from the company's 2500 employees, with a participation rate of 20%.
The survey is structured in five parts (see Appendix A): -Personal data. This section provides an overview of the profile of the employees (anonymously), where they come from, and, therefore, the daily journey they make. -Work schedule. This allows us to calculate the peak hours in the area based on the entrance and exit times of the employees. - Mode of transport to work. The main mode of employee transport is identified, and we ask about their reasons for using that mode of transport. From the point of view of age, the results show a good representation of the employees' considerations towards sustainable mobility because all the main age groups have been represented in similar percentages ( Figure 11). Twenty-six percent of the workers between 51-60 years old and those between 31-40 years old responded to the questionnaire. The intermediate group between 41-50 years old was the most highly represented with 30%. These three age groups represent 82% of the completed surveys. At the extremes, 16% of those surveyed are between 61-70 years old, while the youngest groups represent 2 and 0.2%. The factory's area of influence is regional, including 13 different towns (only 1% come from cities more than 100 km away); 87.7% of the workers come from Cartagena, of which 62% live in the central districts of the city.
In relation to the modal split ( Figure 12), according to the data extracted from the surveys, 67% of employees use cars as their means of transport to travel to work every day, 62% as drivers and only 5% as passengers. As the second and third most popular modes of transport, 14% of workers go on foot and 10% on bicycles, followed by motorcycles with 8%. Scooters are the option for 1% of employees. Therefore, 25% of the respondents use sustainable modes of transport. However, collective modes of public transport, such as buses and trains are not represented in daily use because of their poor operation in relation to the company. Comfort and speed are the main reasons for choosing cars and walking. For car users, increases in travel time are related to traffic jams at departure time (43%) and in the surroundings of Navantia (26%), together with finding a parking space (26%). The average time needed to find a parking space varies between 5 and 15 min.
In order to understand an employee's views about sustainable mobility, preference questions were asked to learn their willingness to use more sustainable modes of transport, considering that improvements are needed. From a pedestrian point of view, 76% of respondents agree that the urban environment is inadequate ( Figure 13). Improvement of pavements, illumination, cleaning and bike lanes are the most frequently requested upgrades. Seventy-seven percent of the employees surveyed confirm the lack of adequate infrastructure for cycling. More bicycle parking spaces closer to the company are requested by 10%. Other options are the implementation of a flexible schedule and offering a bicycle rental service (Figure 14a). In a similar way, increasing the use of personal mobility devices such as scooters depends on having safe and comfortable roads (36%), appropriate legislation (25%) and minor measures, such as charging points, parking spaces, scooter rental services, and a flexible schedule (Figure 14b). To make the public bus service competitive, almost half of the employees ask for better operation with more frequency, appropriate schedules or some improvements in the current routes. Twenty-nine percent approve of a bus service operated by Navantia; that is, a regular service adapted to company requirements. New bus routes and a monthly bus pass are other suggestions ( Figure 15). Therefore, although cars are the most frequently used mode of transport, the surveys show employees' willingness to change to sustainable modes of transport, provided that some improvements were carried out. To sum up, employees support (i) improvement of the infrastructures that provide access to the factory; (ii) consciousness-raising to encourage usage of sustainable modes of transport; and (iii) incentive measures, such as flexible schedules, bus passes and bicycle/scooter rental services.

Proposals for Improvements in Sustainable Mobility
The SWMP should encourage sustainable mobility through the rational use of private cars and make intermodality easier among public transport, bicycles, scooters, and pedestrian areas.
Guidelines and examples of sustainable mobility plans have been studied as references for this project [2,[7][8][9][10]. These references provide an overview of possible measures to promote sustainable mobility. Consequently, a wide variety of measures were identified (see first column of Table 1) and grouped in different policy types: demand management, infrastructure investments, pricing and financial incentives, and traffic management and control. A cross-matrix analysis of the measures and objectives was carried out to select those measures that best contribute to meeting the objectives (see Table 1).
The results of the cross-matrix were assessed by the workgroup to obtain a set of effective measures that realistically fit with the available resources and local circumstances. Accordingly, a shortlist with the most promising measures was obtained, classifying them into three groups: Note that all the measures are required. That is, all of them must be put into practice at the same time to obtain successful results for the company and the city of Cartagena. Next, the main measures studied are explained briefly.

Measures to Improve Accesses
The first measure proposes improving the Elephant walkway. The actions to execute are the improvement of the paved surface (draining pavement), the installation of more streetlamps and the elimination of 109 parking spaces to give more space to pedestrians, bicycles and scooters. To this end, a green path is designed, whose circulation area is shared by the different sustainable modes of transport ( Figure 16). Cars and motorcycles are banned. The estimated budget for this measure is 646,286.59 €. The second measure proposes modifications to the Algameca road to transform it into a cycle-street. More streetlamps and wider pavements are also considered. Traffic diverters and speed humps are placed to reduce the speed of the road to 30 km/h, a safe environment for cyclists and scooter users. On the right side of the road, the embankment is eliminated to gain space for pedestrians and parking areas (84 parking spaces), with a total estimated budget of 505,932.94 € (Figure 17).

Management of Car Park Areas
This set of measures is focused on improvements to the two car park areas ( Figure 18). It is important to note that the measures have not only focused on the organization of the car parks to optimize space, but also on the improvement of the area. Permeable pavement to avoid the accumulation of the water that collects during heavy autumn rainfalls has also been proposed. Moreover, using green or brown pavement and wooden logs to separate the different parking lots provides a pleasant appearance (Figure 19).
A total of 183 parking places are improved with an estimated cost of 353,025.58 € in Car Park 3 ( Figure 19). For the Outdoor Car Park area, 298 parking spaces are optimized together with the adaptation of the entrance and exit gates to facilitate access to emergency vehicles ( Figure 20). The estimated budget for this measure is 179,939.14 €.

Soft Measures
A set of suggestions whose implementation the company could evaluate are presented. For example, 25 new parking spaces for people with reduced mobility inside the company are proposed to achieve the recommended accessibility ratio.
A sustainable option is to provide a bus pass for company employees to foster the use of public transport, in addition to schedule changes adapted to company timetables. Launching a new company bus line for employees could be a good option. Moreover, establishing covered parking lots for bicycles and scooters, or even rental services of these vehicles among employees, are other suggested measures.
Transport by ferry from the Alfonso X pier to Carenero pier, inside Navantia, would be another option, considering shared responsibility for its operation by the Cartagena City Council and the Cartagena Port Authority to expand the use of this service to the city (Figure 21). Different policies related to the reduction of trips to work have also been discussed, such as the implementation of teleworking in some divisions of the company and flexible timetables. Table 2 provides the budgets of the assessed measures. The estimated budgets have been calculated based on an official pricing database, which is produced by an architecture, engineering and construction software every year [26]. The total estimated budget is 2,389,409.64 € (see Appendix B for more detail). It is important to note that, although the budgets of the first two sets of measures are adjusted to real values with a margin of error between 3% and 5%, the budget for the soft measures is indicative. They are estimates based on assumptions about the number of employees to be served. However, it would be necessary to contact specialized companies (depending on the measure) as well as define the scope that the measure would cover and/or the phases of implementation to obtain a more accurate value. An estimated study has been carried out about how much CO 2 would not be emitted by implementing the proposed measures, according to the results of the survey and the preferences for change stated by the respondents. For this calculation, the decrease in kilometers travelled by Navantia employees and the decrease in vehicles that go daily to the company, estimated at 683 vehicles, have been considered. To calculate the savings of kilograms of CO 2 per passenger-km not emitted into the atmosphere, these average values are calculated: an emission of 0.069 kgCO 2 /p-km for buses and an emission of 0.133 kgCO 2 /p-km for cars. These multipliers define the amount of CO 2 emitted per passenger and per kilometer for a given mode of transport [27]. Table 3 provides the savings of kg CO 2 per day of each proposed measure. It is estimated that 805.03 kg of CO 2 /day will not be emitted into the atmosphere. Taking into account 253 working days, an amount of 203,672.04 kg of CO 2 not emitted into the atmosphere per year is obtained. This figure is based on the respondents' answers and considering a change in the mode of transport used by all those surveyed, with 100% exchange preferences (optimistic hypothesis).

Conclusions
The presented project has been motivated by the Navantia company, according to Sustainable Development Goal 11-Sustainable Cities and Communities. It seeks to provide access to safe, affordable, accessible, and sustainable transport systems for all and to improve road safety by means of a Sustainable Workplace Mobility Plan. The main challenge is the location of the company because Navantia is in a consolidated area of the city center with little space available to build new infrastructures. Strengthening positive economic, social and environmental links between the different areas of the city of Cartagena and Navantia are the expected results, thereby fostering local and regional development.
The measures presented in detail in this document reduce the use of private vehicles as the main mode of transport to and from Navantia, offering pleasant pedestrian areas and safety on cycling routes in order to achieve an adequate balance and coexistence among the different sustainable modes of transport. These measures, together with other soft measures that the company could implement, will facilitate the reduction of private vehicle traffic and increase the number of sustainable transport users. The estimated total cost is 2,389,409.64 € and a reduction of 203,672.04 kg of CO 2 emitted into the atmosphere per year has been calculated.
This practical case shows that workplace travel plans do not need to be very expensive, and positive results can be achieved relatively quickly. However, they do require a comprehensive strategic approach and well-designed measures that match the needs of the company and the city.
This manuscript increases the scientific knowledge about workplace mobility plans by applying the Spanish guidelines of the Institute for Diversification and Energy Savings [2]. The results showcase the potential of soft measures to promote sustainable mobility even in consolidated areas with little available space to build new infrastructures. Fostering sustainable mobility implies energy savings and less congestion, considering not only employees but also inhabitants will be benefited.
From this stage, it is essential to agree on clear responsibilities, implementation priorities and timelines for each action [9]. Communication and promotion to political stakeholders, employees and citizens are necessary. Finally, the application of an ex-post evaluation would be useful to compare the theory and practice of workplace mobility plans. Moreover, the reviewing process, evaluating successes and failures, helps to consider new challenges and solutions since mobility patterns change rapidly and the Sustainable Workplace Mobility Plan should be updated to adapt to future trends.

Acknowledgments:
The authors would like to thank all the employees of Navantia-Cartagena and auxiliary companies for their collaboration and the data supplied. Thanks for the help, availability and guidance of Pedro Rodríguez Martínez. The authors would like to thank the reviewers whose comments and suggestions helped improve this manuscript.

Conflicts of Interest:
The authors declare no conflict of interest. The funders had role in the design of the study; in the collection of data and in the decision to publish results. The funders had no role in the analyse or interpretation of data and in the writing of the manuscript.     Appendix B