Fewer trucks, a quiet bus fleet, narrow roadways – these are some of the assumptions to reduce road noise along the new tram route to Mistrzejowice.
We have recently announced that adjustments to reduce the acoustic nuisance associated with car traffic will be requested at the final stage of design works. Their aim is to reduce the number of noise barriers and trees to be removed as requested by the residents.
The design of Tramway route to Mistrzejowice – the last adjustments
The Private Partner has already been asked to introduce changes and the chief designer has been requested to make the necessary adjustments. These are:
- adopting the cross-section of the street in accordance with the current permanent traffic organization: 2×1 plus parking lanes, road width of 6.5 m in total on straight sections and the implementation of a band with a usable width of 0.75 m behind the road, along parking spaces;
- the currently designed sidewalk (that was to serve parking spaces as well) to be converted to green area;
- taking into account the use of a modern, silent tram rolling stock by the carrier;
- limiting the traffic of heavy vehicles and introducing an electric bus fleet;
- applying surfaces with improved noise-reduction parameters for locations particularly exposed to its increased level.
How will the changes affect the schedule?
Within the coming month, the Private Partner will analyze the impact of the changes requested on the costs and duration of the investment. Since their scope does not affect the investment area, the application for ZRID (road construction consent) is not necessary again. The amendment will be made only by means of supplementing the documentation.
Fewer noise barriers, more greenery – these design changes respond to the needs voiced by Kraków’s residents. The ideas include limited traffic on Meissnera Street, electrified bus fleet or the use of a noise-reducing surface.
The tram route to Mistrzejowice is built to facilitate commuting for the residents and to align the space along it to the needs of the local community. This is a major challenge for designers who seek trade-offs to satisfy all users of the new infrastructure.
Tramway to Mistrzejowice – the residents’ voices are heard
Protection against noise is a key aspect of any transport investment yet the construction of noise barriers triggers heated discussions. Having listened to the neighbors of the planned tram route to Mistrzejowice, the investment partners decided to analyze possible changes to the design meant to reduce the noise along Meissnera and Młyńska Streets. A preliminary analysis revealed that the number of noise barriers can be reduced along the investment provided the traffic is limited to a single lane in each direction, the bus fleet is electrified and noise-reducing surface is applied – says Paweł Motyka, Deputy Project Manager at Gülermak. With these changes in place, several dozen trees will be saved that had been originally intended for logging due to a collision with the planned infrastructure. – From day one, we kept repeating the investment would be as friendly to the residents as possible and would not excessively interfere in the public space – says Marcin Hanczakowski, Director of Kraków Municipal Road Authority (ZDMK).
An analysis is currently underway of how the initiated design changes will affect the costs and schedule of the investment which was planned for completion at the end of 2024.
It soaks up rainwater like a sponge, thanks to which it helps prevent creation of the so-called urban heat islands. Such a rain garden will be created near Barei roundabout as part of Tramway to Mistrzejowice (KST IV) the construction project.
The secret of a rain garden lies in the ground of larger permeability and in appropriate vegetation. This combination allows cleaning and collecting runoff water from surface areas much larger than the garden itself. Thanks to the above, smaller amounts of water from sidewalks, streets or bike paths go directly to the sewer system, which prevents the groundwater lowering and local flooding due to heavy rainfalls. These will be the advantages of the garden designed in the area of Barei roundabout, on the southern side of Strzelców street.
Rain garden: what plants are planted there?
What plants are selected for such a garden? The so-called wetland edge vegetation whose roots help eliminate the contaminants run off from streets and sidewalks. Near Barei roundabout, the following plants will be applied: Lythrum salicaria, Eupatorium cannabinum, Hemerocallis x hybrida and Geranium phaeum.
They are planted in specific soils, where a bacterial membrane can be created which additionally reduces the contamination. It is like a small local biological treatment plant! In the subsoil, sands, limestone and volcanic rocks are used whose permeability and porosity are significant thanks to which runoff can be intercepted.
What are the three basic goals of any construction project? Complete the investment, stay within the budget and meet the deadlines. A project implementation schedule helps in achieving the third one. It is prepared long before the day one at the construction site.
Most of the construction projects would have remained just plans without a well-conceived schedule – a one just like that was prepared by the Private Partner as part of the construction of the tramway route to Mistrzejowice. Let’s take a closer look at the KST IV project which involves much more than just the construction of tramway tracks and overhead power supply. It includes the alteration of a number of underground systems (even a river channel), road, bicycle and pedestrian infrastructure, vegetation, managing the construction site environment, information campaigns and effective financing of works. Coordinating it requires a good plan. That’s not all: the entire project is planned for almost a quarter of a century, because it is implemented in the public-private partnership formula (PPP).
Schedule to support project implementation
Naturally, this does not mean the construction will take that long. The PPP contract covers not only the implementation of the project, but also the maintenance of the ready infrastructure for a period of 20 years. Potential private partners were aware of it upon filing bids in the PPP procedure. The design and construction period was scheduled for 40 months with the countdown off in December 2020 when the contract was signed.
According to its provisions, the project implementation schedule was to be presented to the public entity within the first month of cooperation. “However, I would not reduce this document only to a mere contractual requirement. It is primarily a practical support for the team preparing and implementing the project. It supports adding the right items to this complicated puzzle at the right time” – says Wiktor Walicki, Planning Engineer with Gülermak.
Can the schedule be changed?
The most important elements of the KST IV implementation schedule are: developing a design concept, completing the design stage, filing a request for ZRID (road construction consent), starting construction, starting technical acceptances, launching tram connection and further – its operation period. Their timing became binding after the public entity has approved the schedule. What about changes? They are allowed, but their source must be a significant and unexpected circumstance.
That was the case with the study of the construction of the first line of the Kraków pre-metro. It revealed that on the section between the Park Wodny and the Młyńskie roundabout, the route of the new means of transport will be identical as the tram route to Mistrzejowice. “In order to adapt this part of the route to service additional and longer cars, we recommended its appropriate redesign” – says Marcin Hanczakowski, Director of Kraków Municipal Road Authority (ZDMK). Updated at the end of last year, the investment implementation schedule now assumes that the route will be operational at the turn of 2024 and 2025.
*This is the first in a series of articles on schedules and time management at construction sites. More to come soon.
Convenient access to housing estates, quite a lot of greenery, new lighting – this will be the new look of the Mistrzejowice terminus.
The tram terminus in Jancarza Street, constructed in the 70s, is going to undergo an extensive reconstruction. The terminus, opened on 29 November 1974, made quick carriage of passengers between Hipokratesa roundabout and Mistrzejowice possible. In 2024, also the route in a westerly direction will start here as part of KST IV project.
Mistrzejowice terminus tailored to the 21st century
The whole area will be newly developed: lush vegetation, new LED lighting, bicycle parking and convenient footways adjusted to the needs of people with disabilities will be provided. Residents of neighboring estates will benefit most from this reconstruction. Transfer to buses operating from a neighboring bus terminal will be much easier – the existing crosswalk will be moved westwards, thanks to which the distance will be shorter. Four comfortable tram platforms will be 65 meters long, which means that they will be significantly longer than the present ones, thanks to which passenger ingress and egress will be safer. At each of them, there will be waiting shelters with modern passenger information boards next to them. A new traffic control point will be constructed which will serve also as tram drivers’ facilities. The area between Jancarza, Załuskich and Kolbego Streets will be tailored to the 21st century.
Facilities for all traffic participants
A new dedicated bike path will be constructed on the southern side of Jancarza Street, reaching the terminus. It will be connected to the existing shared zone on the eastern side of the terminus. In order to meet the expectations of the residents, an additional lane was designed for turning right from Jancarza Street into Załuskich Street. This will be of benefit not only to those using public transport, but also to drivers and cyclists.
Since the new infrastructure is to be created at the location of an operating tram terminus, the matter of keeping the tram traffic during the construction works has to be solved. – The operation of the terminus will be undisturbed for most of the duration of the construction works. The traffic will be suspended temporarily for the planned integration of the new infrastructure, during which passengers will use replacement transport service. Those changes are scheduled for 2024 and will last no longer than a few months – says Wojciech Janosz, site manager from Gülermak – the company implementing the project.
There will be displays showing the estimated time of arrival of trams on each stop on the route to Mistrzejowice. Traffic Tram Supervision System (TTSS) is the source of this practical information.
Time is money so we appreciate modern technologies thanks to which we may efficiently and quickly get from A to B. Passengers of public transport in Kraków have been enjoying the benefits of TTSS for 14 years, which streamlines the management of urban transport in real time. Data from one of the system providers shows that TTSS supported shortening travel time by tram from Krowodrza Górki to Kurdwanów from 42 to just over 37 minutes. Together with the area-wide traffic lights control system, it helps residents save time on the way to work or school on a daily basis. The same software is used by some of the biggest cities worldwide: Zurich, London, Riyadh, Singapore and Bonn.
Tramway to Mistrzejowice comes together with a dynamic passenger information system
The TTSS comes with a bonus: a passenger information system with over 300 electronic displays placed throughout the city showing estimated time of arrival of trams and buses and their final stop. The displays may be also used to quickly spread any messages, e.g. about changes in traffic organization or detours. The practical information is driven by advanced solutions that will also be applied on the tram route to Mistrzejowice.
Dynamic passenger information system – how does it work?
How do the displays “know” when the vehicle we expect arrives? How is the data displayed actually updated? The heart of the dynamic passenger information system is the route information controller located in the dispatcher of ZDMK and the MPK carrier. Data on the actual position of vehicles that are currently on the routes are provided by GPRS transmitters installed in them based on the GPS location. Advanced prediction algorithms, supporting precise prediction of departure times from stops, process them, also using historical data. This is how you get reliable information.
In order for the correct arrival times to be displayed at the specific stop, a broadcast system is needed. It uses optical fibers or GPRS. Effective data delivery requires not only the installation of displays (at each stop on the tram route to Mistrzejowice), but also underground infrastructure which was ensured already at the design stage.
The contractor of the tram route to Mistrzejowice will apply a special mineral-asphalt mixture to reduce traffic noise even more effectively. Together with other solutions that suppress noise and vibrations, it will ensure everyday comfort for the residents.
The so-called ‘noise reducing’ surface is a solution that reduces the noise level associated with car traffic. For the sake of simplicity: it is more porous than a traditional wear layer. The air that collects in it supports absorbing some of the noise generated as a result of rolling wheels. The noise-reducing surface will be applied on the pavements reconstructed as part of the Tram to Mistrzejowice project. They will be placed in the area where tests revealed permissible noise standards may be exceeded.
Noise-reducing surface fitting urban conditions
According to the decision of environmental conditions, at least an SMA8 surface is required yet its properties work better on highways or expressways than in urban conditions – they reduce noise at higher speeds. In order to best match the designed solutions to the conditions in which the new infrastructure will operate, the private partner suggested using a different mixture: BBTM. It works well also on local roads where cars move slower.
“The designer’s assumptions for our investment, supported by research, imply that the BBTM pavement will reduce noise by approx. 4.5 decibels, while the previously proposed SMA8 mixture would provide a reduction of 1 decibel” – says Agnieszka Gurgacz, environmental protection specialist with Gülermak.
Protection against vibrations and noise
Together with the system reducing noise and vibrations from the trackbed area, vibration damping mats, green trackbed and noise barriers, the noise-reducing surface will ensure compliance with environmental quality standards in terms of noise as required under such investments. This condition could not be met when using SMA 8.
“We do not use BBTM surfaces in Kraków. The first one ever will be used in the Tram to Mistrzejowice construction. We hope that this technology will bring good results” – says Marcin Hanczakowski, Director of Kraków Municipal Road Authority (ZDMK).
The tunnel in the central part of the tram route to Mistrzejowice requires the heaviest workload in the project. It will be constructed with the use of the top-down method on diaphragm walls. Here is an overview of individual steps.
Usually, before a tunnel is constructed within developed areas, buried utilities conflicting with the planned structure are relocated. In such a way, the site is prepared for further works, and residents of the neighboring areas are provided with continuous supply of all utilities. In the area of Polsadu roundabout, the network of underground utilities is dense, therefore, it was a huge challenge to design new routes for the water main, gas main and sewer piping.
Construction of a tunnel on the route to Mistrzejowice requires also that the underground stream Sudoł Dominikański running currently mostly under the median strip between the roadways of Młyńska Street is relocated. – According to the design, the stream will be moved under the western roadway of Młyńska Street and led in a southerly direction up to Młyńskie roundabout – explains Ewelina Woch, structure coordinator in Gülermak.
What are diaphragm walls and how are they constructed?
Once the site is prepared for construction works, trenching of diaphragm walls (d-walls) is commenced, that is of RC structural walls constructed in a narrow trench. They form the tunnel lining, transfer soil and groundwater pressure. They also minimize the impact of the excavation on the neighboring buildings and protect the tunnel against underground water inflow. Thanks to their structure, they can transfer significant loads and provide tunnel stability in such a way.
How are they created? First, a narrow and deep excavation is made with the use of a grab (in the case of KST IV, the excavation depth will reach from 11 to 24 m). Then, a reinforcement cage is placed in the excavation and filled with concrete with the use of the tremie method. It consists in concreting the wall upwards from the excavation bottom. When such walls are ready, construction of the top slab, that is, the bearing upper slab of the tunnel can start.
Top slab, excavation and bottom slab
The top slab is made on the ground, on a layer of lean concrete, with the use of waterproofing membranes. Once the upper slab is ready, the excavation can be commenced.
There are two methods of extracting soil from the tunnel: the top-down method and the boring method. – In order to extract spoil in the top-down excavation, a construction opening should be kept in the top slab, whereas in the boring method, soil is excavated from the tunnel portal. Both the methods will be used during the construction of KST IV – says Ewelina Woch.
Then, bottom slab of the tunnel has to be installed which is to be made on a layer of lean concrete – as in the case of the top slab. Its important element are membranes protecting the tunnel against groundwater permeability.
Finishing and fitments
After completion of structural works, the tram trackbed and various systems will be constructed, among others: water supply, catenary, telecoms and storm sewer systems. Also finishing works will be carried out in the tunnel for which fitments will be provided for the purpose of circulation, safety and traffic control. At this stage, also works on the ground surface are performed – necessary infrastructure is restored, vegetation is introduced in the area by means of adequate plant species.
Construction of the tram route to Mistrzejowice is a practical response to the objectives specified in the Climate change adaptation plan for the City of Kraków until 2030. This will lead to reduction of traffic pollution and increased resistance of the transport sector to adverse effects of extreme weather events.
One of the most important objectives of Kraków is to reduce air pollution emissions. Particulate matter, sulfur oxide, nitric oxide – dispersion of these substances which are hazardous to health can be stopped. The actions taken however have to be diversified. One of the tools is to encourage as many residents as possible to use collective transport and to show that there is a more eco-friendly alternative, e.g. riding a bike or using public transport. However, in order to convince the motorists of Kraków to change their habits, a friendly infrastructure is indispensable.
Construction of a fast tram connection between the densely populated area of Mistrzejowice and the city center will be a special response to the residents’ need to be provided with well-organized collective transport in this part of the city. A dedicated tunnel, traffic control system, modern rolling stock powered by “green” energy – all that is to encourage residents to leave their cars parked and take the public transport.
Blue-green infrastructure for northern Kraków
The project will also lead to reduction and mitigation of effects of high temperatures and heavy rainfalls which have an increasing impact on the cities at our latitudes, since the tram route project is to be accompanied by the so-called blue-green infrastructure along the tracks: green trackbed increasing the natural water retention, “green” passenger waiting shelters, wildflower meadow, shared foot and cycleways as well as solutions for the elderly and people with disabilities. Also, compensation plantings are planned (1:1); they will include species resistant to difficult urban conditions, among others: drought, salinity or freezing.
The project includes a partial modernization of the drainage system in the area where the tram route is to be located, which will also have an impact on water retention in case of rainstorms.
Tram to Mistrzejowice powered by clean energy
Modern, quiet and energy efficient rolling stock which will run on the designed route does not need fossil fuels to transport the passengers. It is electricity powered – in Kraków, it is “green” energy from renewable sources which are climate neutral. On the basis of a 2-year contract with a big energy company, Kraków is provided with supplies of clean power, used i.a. for trams.
As part of the project of the tram route to Mistrzejowice, also the use of small photovoltaic systems, producing power for the operation of the route is being considered. They could be installed e.g. on some of the waiting shelters, providing self-sufficient power supply for lighting.
Local governments in Poland and throughout Europe are seeking opportunities for quick and effective development. Just like Kraków, they are choosing the PPP formula to offer residents the highest quality services without overburdening budgets.
Polish cities are developing intensively which triggers major investment needs. The big question is where to get money for the construction of roads, schools, water supply and at the same time not to neglect the maintenance of the existing infrastructure. Each infrastructure project is a burden on the budget (own contribution, loan) and affects the overall investment plans. To respond to these dilemmas, regulations were put in place to facilitate the public-private partnership (PPP) model which generates virtually no costs for the local government at the construction stage. It does not require a time-consuming search for financing and does not affect the local government’s debt ratio. A private partner performing the task receives the first payment only after the residents start using the new infrastructure.
PPP: spending money more effectively
According to the Ministry of Funds and Regional Policy, 165 PPP contracts have been made in Poland since 2009, mainly covering projects in the field of energy efficiency, sports and tourism and transport infrastructure. Not an impressive number yet the interest in PPP is growing year by year. 68 projects are currently being prepared which will potentially be implemented in this formula. Most of them are for the transport infrastructure. They are estimated at a total of PLN 8.3bn.
“There are not many projects of this type on the market right now, but this should change in the coming years. We can clearly see public awareness and practice is being developed in this matter, which makes potential private partners – who are ready and willing to participate in tender procedures – very happy” – says Michał Wójcik, COO with Gülermak, in a recent interview for inwestycje.pl website.
Awareness is growing and advantages seem attractive. What are these? “Number one, from the perspective of public finance: it is cheaper – says Marcin Hanczakowski, Director of Kraków Municipal Road Authority (ZDMK) in an interview for transport-publiczny.pl whose institution is developing the tramway route to Mistrzejowice in partnership with Gülermak. “The amount [approx. PLN 1.3 billion – ed.] includes not only the construction of approximately 4.5 km of the route, but also its maintenance for the next 20 years. Afterwards, the partner will hand us over the route already renovated” – he adds.
“The second advantage is completion time. A private partner is not restricted by various procedures binding on the public sector – it implements the investment faster, with fewer risks, and has wider access to appropriate human resources and new technologies”.
Several European countries can boast of a really wide and effective use of PPP. According to the latest Review of the European PPP Market in 2020, 34 PPP transactions reached financial close. The biggest number of such projects was launched in France (e.g. the RCEA route, consisting of a series of roads connecting the east and west of the country) while the projects performed in Germany were of the highest value (e.g. extension of the A3 motorway). In general, transport sector tasks are predominant and are considered to be the most promising for the PPP model.
The tramway to Mistrzejowice is not the only investment of this type in Europe. The first tramway route is currently being developed in Liege and is scheduled for completion in 2023. For several years, routes built as part of PPP in Zaragoza and Dijon have been successfully operating. Success stories are there and once the investment is completed, it is worth passing on the experience.
Kraków as the role model
The tramway to Mistrzejowice is already today labeled the largest transport project in Poland made in the PPP formula. Kraków is supported by the government in its preparations and partnership while the private partner is approaching international funding institutions. Kraków’s experience will serve as the basis for developing guidelines for other cities planning to leverage on the PPP while implementing their projects aimed at serving the residents.