Conference Program > Gignac technical tour (14/10/2015)

General Information

Place: The Gignac Canal

Date and time slot: Wednesday, October 14, 2015, 09:00-12:30

Accessibility: free, subject to availability (for logistic reasons and in order to guarantee your place, we recommend you to book your visit on-line)

Supervisor: Céline Hugodot

Details

The ASA of the Gignac Canal is an Association located in the middle valley of the Hérault, 30 km north-west of Montpellier. It brings together landowners within a perimeter of 3000 ha.

The Authorized Syndical Association was founded in 1879. It aims to create and maintain a Canal derived from the Hérault River in order to supply water to the concerned perimeter.

With 50 km of transport networks (primary network) and 250 km of distribution networks (secondary network), it allows water to be taken from the Hérault River (the sole source) and to serve some 10,000 plots belonging to 4 000 members of the perimeter, spread over 11 municipalities. The irrigated area is occupied by 67% of vineyards and 22% of diversification crops or gardens. Approximately 10% of the perimeter is occupied by quarries and sandpits, at different stages of exploitation.

Historically gravity-fed and organized around a water tower, water distribution among users has been the subject of a modernization program since 1990. The program aims to eventually implement a full conversion of networks towards a continued water supply under pressure. This modernization is required due to the scarcity of water resources and the need to organize the sharing between different users (drinking water, swimming, tourist use, fishing, aquatic needs, and irrigation). It consists of conversion of gravity-fed aboveground distribution networks to buried pipelines under pressure.

Beyond the ecological interest, this modernization is an important factor for local development in agriculture, as well as for other uses (recreational use, use of raw water for industrial processes). It allows for a significant reduction in water withdrawals (efficiency gain), and enhances ease of use by adoption of innovative irrigation systems (in-field drip irrigation, fertirrigation, automation of watering systems, etc.).

In 2015, nearly 40% of the perimeter provides distribution under pressure (overpressure at minimum 2 bar, with 150 micron collective filtration), one third of the perimeter is equipped with underground pipes allowing a continued water service without pressure and only 30% still operates traditionally. The modernization program (Canal Contract) is expected to be finalized in 2018.

Program

9:00 - departure from the Corum by bus

9:45 - the Canal water intake in the Hérault River at la Combe du Cor

10:30 - visit to an overpressure station in a recently modernized sector. Comparison with a gravity-fed sector

12:00 – return to the Corum

Pictures