Project implementation
The main stages of the project
- 2016 - Declaration of Public Utility
- 2018 - 2019 - Finalization of the preliminary design and project studies
- 2020 - 2022 - Diversion of concession networks and award of works contracts
- Since the beginning of 2023 - Infrastructure works : creation of new lanes dedicated to buses (dedicated lane), adaptation of the existing dedicated site to 24-metre buses, transformation of bus 402 stops into more spacious and comfortable Tzen 4 stations, ...
- From summer 2024: equipment tests, bus traffic tests, dry runs
The actors of the project

Île-de-France Mobilités

As the transport organising authority in Île-de-France, Île-de-France Mobilités imagines, organises and finances innovative solutions to meet all types of mobility. Listening to the people of the Ile-de-France region, she works every day to improve their daily journeys. To do this, it has embarked on an ambitious programme to modernise transport with unprecedented budgets (new trains and buses, reinforcement of bus lines,...). Île-de-France Mobilités is constantly investing to improve accessibility in stations, which helps to improve the comfort of travel for all Ile-de-France residents. More resources are also being deployed to improve passenger safety (reinforcement of the human presence on the ground, development of video protection, etc.). Île-de-France Mobilités is also thinking about mobility in the broad sense by offering Ile-de-France residents new mobility solutions for their travels: Park and rides, parking spaces for bicycles with Véligo spaces near stations, development of micro-working spaces in stations, etc. Île-de-France Mobilités is constantly imagining new services to make your journeys simpler and smoother, with a transport network that is growing every day. Île-de-France Mobilités finances 100% of the rolling stock and operation of the Tzen 4.
The State

By financing up to 21% of the Tzen 4, the State is committed to offering Ile-de-France residents more efficient transport that will allow them to move towards a sustainable city and a more peaceful lifestyle. The State is pursuing its objective of making the transport network more efficient by making it part of the dynamics of the territories in order to better meet the daily needs of users, to improve access to transport for all and thus strengthen the attractiveness of the Île-de-France region.
The Île-de-France Region

Together with Île-de-France Mobilités, the Region has been engaged in the transport revolution since 2016 to profoundly improve the transport conditions of Ile-de-France residents. The creation of new bus lines is part of this major programme, and the Region is therefore devoting significant financial resources to it. The Region was then the main financier of the project, providing 49% of the cost of the work.
The Department of Essonne

In order to best meet the needs essential to the development of the territory, the Department of Essonne is devoting 450 million euros to mobility for the period 2017-2021. This investment contributes, in particular, to the development of a structuring public transport network aimed at strengthening the territorial network, to promote exchanges with the major economic centres and to facilitate access to the regional network (RER, Grand Paris Express) for Essonne residents. It also makes the road a major lever for improving travel and contributes to developing the use of alternative and active modes.