Technical Visit

The technical visit will take place on the 11th February 2011. The visit is expected to include*:

- Paradela dam (concrete faced rockfill dam, completed in 1958, maximum height of 112 m) and spillways (old and new);
- Venda Nova repowering schemes: Frades/Venda Nova II (under operation) and Venda Nova III (under construction) underground powerhouses;
- Salamonde dam (arch dam, completed in 1953, maximum height of 75 m), new spillway and repower hydraulic circuit intake (under construction).

(*Eventual need of readjustment, depending on the weather conditions)

Maximum number of participants: 60

Pre-registration is required. Please, send form to ishs2012@aprh.pt

Deadline for sending pre-registration form: January 20, 2012

There will be a charge of €30,00, which will include transportation and lunch.

Payment to be completed by February 9, 2012 (12h00) at the Secretariat desk in the Hotel Porto Palácio, Porto.

Technical Visit Programme

07h15	Meeting at the main entrance of Porto Palácio Hotel
07h30	Bus leaves Porto Palácio Hotel
09h30	Paradela dam arrival
09h30 - 10h15	Outdoor visit to Paradela dam and spillways
10h15	Bus leaves to Frades/Venda Nova II powerhouse
11h00	Frades/Venda Nova II powerhouse arrival
11h00 - 13h30	Visit to Frades (under operation) and Venda Nova III (under construction) powerhouses (*)
13h30 - 15h00	Lunch in Venda Nova II powerhouse (*)
15h00	Bus leaves to Salamonde dam
15h45	Salamonde dam arrival
15h45 - 16h30	Outdoor visit to Salamonde dam, new spillway (under construction) and repower hydraulic circuit intake (under construction)
16h30	Bus returns to Porto
18h00	Arrival to Porto (Porto Palácio Hotel)

(*) Frades (Venda Nova II) and Venda Nova III powerhouses are underground facilities.

General Information

Located in the northwest of Portugal the Cávado river basin has about 1589 km2 and serves several hydroelectric power schemes with dams placed in cascade. Those power plants and dams were built between the 50’s and 80’s, the first, Venda Nova (1951), located in the Rabagão river, and the last, Vilarinho das Furnas (1987), in the Homem river. Those two rivers are the biggest tributaries of the Cávado river. There are 7 large dams (Alto Cávado, Paradela, Salamonde and Caniçada in Cávado river, Alto Rabagão and Venda Nova, in Rabagão river, and Vilarinho das Furnas in Homem river) ranging from 75 to 110 m high, built with different technologies (concrete arch, concrete gravity, uncompacted rock-fill). Their net storage capacity amounts to 1127 hm3.

Pelton, Francis turbine and pump-turbine units are installed in the six power plants with a total output amounting to about 622 MW and a mean annual production of 1762 GWh. The last power plant to be built, Frades (or Venda Nova II), is located between Venda Nova and Salamonde reservoirs and consists of a cavern powerhouse where two Francis pump-turbine units are installed with a rate flow of 25 m3/s each, and a gross head of 422 m. It started its operation in 2005. The hydraulic circuit consists of an unlined headrace tunnel with about 2800 m long, an unlined tailrace tunnel 1380 m long and two surge tanks located upstream and downstream of the powerhouse.

Apart from structures in operation and its diversity, there are also plants under construction, corresponding to the repower of Venda Nova III and Salamonde II, one plant in design, the repower of Paradela II, and the two new spillways of Paradela and Salamonde, both under construction.

Combining all of these great engineering structures with the idyllic Cávado valley partially inserted in the Peneda-Gerês National Park and the region superb cuisine, benefits the expectation for a promising technical visit.

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