Frequently asked questions

In the early 1990s, in order to better manage real-time hydrological information on the Rhône and its tributaries, CNR began modernizing its measurement network and developed a centralized acquisition and processing system.

To compensate for the lack of information of the public, the CNR had decided to put at your disposal the information of its main hydrometric stations, in particular the ratings and flows of the Rhône and its main tributaries. The public could thus access live information on the floods and their evolutions by a Minitel service (1993).

The Minitel service was replaced by a voice server and a website in 2005. These services are particularly requested during each hydrological event on the Rhône. For example, the voice server totaled more than 5,000 connections in 4 days between December 2 and December 5, 2003.

The flows rates presented in the bulletins are hourly averages.

The odds presented in the ballots are hourly averages.

Uncertainties for flow rates are evaluated under normal conditions at about 10%.

However the information comes from automatic recording in real time. For reasons beyond our control, the rates and / or levels for a given station may be erroneous or unavailable. CNR is doing everything possible to restore them as soon as possible.

RNPC ZOOM :

You will also see differences between the values ¿¿displayed for the same station on the RNPC part and on the other hydrological information part. Indeed, only the 6 reference stations presented on the RNPC page of the Inforhone site are valid for triggering and removing RNPCs. The flow rates of the RNPC reference stations have acquisition time steps and delivery frequencies adapted to the RNPC triggering system. The other data of the Inforhone site have different time steps (average hourly data or daily average of the hydrological part for example) and can not, as such, be used to infer the state of a sector RNPC.

Article 14 of law no. 2003-699 of 30 July 2003 relating to the prevention of technological and natural risks and the repair of damage stipulates that the State is responsible for the organisation of monitoring, prediction and the transmission of data relating to floods.

In the case of the largest rivers (especially due to their hydrology, the high number of communes located on surrounding floodable areas and the damage floods can cause), the State ensures the transmission of information on floods and their prediction, when technically possible, at an economically acceptable cost.

However, the responsibility of the State is not exclusive in this area: wherever the State does not fulfil the role of transmitting flood information, local authorities may carry out a feasibility study of monitoring and warning systems and install them if the conclusions of these studies are positive. These actions require efficient coordination and compatibility with the systems installed by government services.

Therefore, in 2003 the State started to reform the organisation of flood warning systems. The first step of this reform consisted in setting up the Central Hydrometeorological and Flood Prediction Support Service (SCHAPI), based in Toulouse. The second step consisted in reorganising the map of flood warning services by grouping a small number of services responsible for flood prediction and warning (SPC)."

The above is an extract of the Flood Warning Master Plan – Rhône Mediterranean Watershed drawn up by the watershed delegation of the DIREN Rhône-Alpes (Ministry of the Environment), in March 2005 by virtue of the application of the ruling of 12 January 2005 and the ruling of 15 February 2005. The full text of the master plan, which specifies the organisation and system set up, is available on the following internet site www.rdbrmc.com.

CNR participates in this system by making its own data available and transmitting (by fax, email, etc.) data regularly on the progression of flow-rates and levels on the Rhône during flooding. CNR shares access to a certain number of hydrometric stations on the Rhône and its tributaries with government services.  

CNR has compiled archives of flow rates and levels at several measurement stations on the Rhône and its tributaries. Some series are recent while others provide measurements from over a century ago. They gather historic measurements and processing results station by station, particularly:

• average hourly heights,
• average hourly flow rates,
• average daily flow rates,
• average monthly flow rates,
• and tables of classified flow rates

Specific processing can be requested by email to cnr.lyon@cnr.tm.fr

or by letter to CNR, 2 rue André Bonin 69 316 Lyon cedex 04, France.

We advise you to contact VNF ¿¿for any question regarding the applicable regulations.

You can also consult their site vnf.fr

This is a notice to the inland waterway which summarizes for a waterway all the conditions of navigation, the existing infrastructures, the peculiarities .....

This is a very useful document.

You will find it on the website of Voies navigables de France vnf.fr

CNR have edited two booklets intended for yachtsman :

For navigation from Lyon to the sea, booklet "The Rhône from Lyon to the sea":

https://www.cnr.tm.fr/wp-content/uploads/2019/04/memo-2018-bas-rhone-bat19062018-1.pdf

For navigation on the upper Rhône, booklet "Locks on the upper Rhône" :

https://www.cnr.tm.fr/wp-content/uploads/2020/09/memo_passage_des_ecluses-Ht-Rhne.pdf

I am yachtsman, must I equip myself with a VHF to sail on the Rhône ?

CNR STRONGLY recommends boaters to equip themselves with a VHF to navigate the Rhone, in order to easily communicate with other sailors and lock keepers.

* The lock of Savières (PK132) makes it possible to connect the Rhone River (Belley Falls reservoir) to Lake Bourget via the Savières canal.

The lock operates in "self service".

It is open all year 24 hours on 24, except period of unemployment.

* The locks of Chautagne and Belley (2 times 2 locks) are self-service on their opening hours which are :

* The locks will be closed on: January 1st, November 11th, and December 25th.
   

The passage in the locks of the low - Rhone is possible all the year, 24 hours on 24 except :

• during three non-working days: 1 January, 11 November and 25 December,

• and during periods of unemployment.

! Between 9pm and 5am, the locks are open only for commercial vessels and for passenger boats, excluding pleasure boats.

Seafarers must announce their passage by night before 20:30 at the latest by phone or VHF at the last lock encountered, or otherwise by phone at the 04 75 50 97 50 (Centre de Gestion de la Navigation).

L'éclusage des plaisanciers à l'écluse de Port-Saint-Louis-du-Rhône se fait dans les conditions suivantes: